Renewable energy

Venture Capital Rushes Into Alternative Energy

2009-07-22T10:18:00.000+05:30

Money is flowing into alternative energy companies so fast that “the warning signs of a bubble are appearing,” according to a report on investment in clean technology by a New York research firm, Lux Research.

The report also suggests that companies that make equipment to cleanse air or water, or that process waste, have been overlooked by investors.

Matthew M. Nordan, president of Lux, said that the amount of venture capital put into clean energy investments last year was $1.5 billion, up 141 percent from the $623 million of 2005, and that in the same period, initial public offerings by companies in this sector rose to $4.1 billion, from $1.6 billion in 2005.

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7 amazing facts about renewable energy

2009-06-19T18:43:00.000+05:30

The Sustainable Energy Coalition is hosting a big energy expo in D.C. today, and they have assembled a nice collection of interesting factoids about renewable energy. Here are 7 facts about the renewable market you probably didn't know:

. . . that renewable energy sources provided nearly 10% of both domestic energy production and U.S. electrical generation in 2008 with non-hydro renewable electricity expanding by 17.6% over the previous year; renewable energy will account for about a third of new electricity capacity added to the U.S. grid over the next three years.

. . . . that U.S. wind power grew by 50% in 2008 and accounted for 42% of all new power generation in the United States last year; wind energy could supply at least 20% of U.S. electricity needs by 2030 while avoiding 7.6 cumulative gigatons of carbon dioxide.

. . . . that grid-tied photovoltaic (PV) capacity increased 58% in 2008 and solar water heating capacity increased 40%; the PV industry today is 10 times larger than 1998 and likely to grow by 50% annually in the coming years; solar thermal plants covering an area equal to 9% of Nevada could generate enough electricity to power the nation; solar power is on the verge of reaching cost parity with conventional energy sources.

. . . . that there may be more than 90,000 MW overall of untapped water potential in the United States; through new hydropower technologies, such as advanced turbines, and new applications, such as tidal, wave, ocean currents, and in-stream hydrokinetic approaches, the industry could double its output over the next 20 years.

. . . . that six million Americans are using geothermal energy in their homes – three million receive electricity from geothermal power plants and another three million use geothermal heat pumps to heat & cool their homes; more than 100 new geothermal power projects now under development in 13 states will more than double the county’s geothermal capacity over the next five years.

. . . . that total ethanol capacity expanded 34% and E85 stations exceeded 1,800 in 2008; the fuel now represents more than 7% of the nation’s gasoline supply and can be found in more than 70% of gasoline gallons sold in the U.S.; the 6.5 billion gallons of ethanol produced last year added $47.6 billion to the nation’s GDP; moreover, cellulosic ethanol requirements are projected to boom during the coming decade.

. . . . that biomass is presently the largest U.S. renewable energy source with more than 200 existing biopower plants now providing electricity for 1.5 million American homes; manure-to-energy biogas projects are expanding and could power up to 3% of North America’s electricity needs.

What's The Advantage Of Renewable Energy?

2009-06-19T18:41:00.000+05:30

So you want to know what is the advantage of renewable energy?

Thank you for visiting this page where you will learn about some obvious, and some not so obvious advantages of renewable energy.

Well, when using energy from sources that are easily replaced, you are using renewable energy.Examples are the use of sunshine, wind, flowing water, biological- and geothermal processes. They are often described as clean and green forms of energy because of their minimal environmental impact compared to fossil fuels.

One advantage of renewable energy therefore is the more sustainable use of finite sources of energy.

You probably are aware of that advantage already. But of course there is more. And by the way, there is much that you can do yourself about using renewable energy.

And many ready-made solutions to applying renewable energy in your home exist. Click here to visit the Alternative Energy Store for discount prices on solar panels, wind turbines and renewable energy equipment for your home.

No carbon-based planet warming and polluting

The advantage of renewable resources includes their inability to produce carbon-based warming and polluting agents into the atmosphere. The financial cost of its applications is not always cheap but if the environmental costs of using fossil fuels are accounted for, renewable energy wins hands-down. There are also indirect savings on health and its costs as there are no harmful emissions.

The great advantages of renewable energy then are:

We can use it repeatedly without depleting it.
No contribution to global warming,
No polluting emissions
Low cost applications when counting all costs
Saving on health and its costs

But there is still more.

Scientists make solar energy breakthrough

2009-06-17T12:31:00.000+05:30

Researchers at Canada's National Institute for Nanotechnology (NINT) and the University of Alberta say they have engineered an approach that is leading to improved performance of plastic solar cells (hybrid organic solar cells). The development of inexpensive, mass-produced plastic solar panels is a goal of intense interest for many of the world's scientists and engineers because of the high cost and shortage of the ultra-high purity silicon and other materials normally required.

Plastic solar cells are made up of layers of different materials, each with a specific function, called a sandwich structure. Jillian Buriak, a professor of chemistry at the U of A, NINT principal investigator and member of the research team, uses a simple analogy to describe the approach:

"Consider a clubhouse sandwich, with many different layers. One layer absorbs the light, another helps to generate the electricity, and others help to draw the electricity out of the device. Normally, the layers don't stick well, and so the electricity ends up stuck and never gets out, leading to inefficient devices. We are working on the mayonnaise, the mustard, the butter and other 'special sauces' that bring the sandwich together, and make each of the layers work together. That makes a better sandwich, and makes a better solar cell, in our case".

After two years of research, these U of A and NINT scientists have, by only working on one part of the sandwich, seen improvements of about 30 per cent in the efficiency of the working model.

Michael Brett, professor of electrical and computer engineering, NINT principal investigator and member of the research team is optimistic saying: "our team is so incredibly cross-disciplinary, with people from engineering, physics and chemistry backgrounds all working towards this common goal of cheap manufacturable solar cells. This collaboration is extremely productive because of the great team with such diverse backgrounds, [although] there is still so much more for us to do, which is exciting."

The team estimates it will be five to seven years before plastic solar panels will be mass produced but Buriak adds that when it happens solar energy will be available to everyone. She says the next generation of solar technology belongs to plastic.

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The Solar Energy Breakthrough Will Change the Energy Business Landscape

2009-06-17T12:24:00.002+05:30

The cost of solar modules has fallen substantially over the past six months and is expected to fall still further. Photovoltaic solar energy is nearing its breakthrough point. This will happen once the cost of solar electricity equals the cost of electricity from the grid.

That point is referred to as "grid parity" and will vary from country to country depending on the market segment. In sunny California, the grid parity point for private households is near, as solar irradiation is high and consumers pay a high price for their electricity. In France– a little less sunny and with low electricity costs due to its cheaply available nuclear power– grid parity is a little further away.

Nevertheless, grid parity for solar PV will come to all countries eventually, because the cost of solar electricity will continue to fall, while the cost of electricity generated through fossil fuels will only increase. Solar modules and systems will become cheaper as a result of improvements in technology and the scaling up of manufacturing processes. The cost of electricity from the grid will become more expensive as a result of growing demand and the scarcity of fossil fuels. Increasing environmental concerns translating themselves into eco-taxes may raise the price as well. Grid parity could be reached in California and southern Italy in less than two years, while it may take a little longer in other countries, such as Spain, Portugal, and Greece. Other countries will soon follow suit. What can we then expect?

Once grid parity has been reached, consumers will be presented with a choice: (1) to buy all their electricity from traditional energy utilities or (2) to pay the same price and (partly) generate green renewable solar energy from their own roofs. Not only will the growing focus on green and sustainable development make solar power a preferential alternative, but even more important will be price stability. Following its installation, a solar energy power system will generate solar electricity at fixed cost for at least 25 years. Operation and maintenance costs are negligible. The cost of solar electricity will be determined by the depreciation schedule and the interest rate. Both of these can be forecast over a long period of time. Compare this to the annually changing cost of grid electricity. Is it likely that fossil fuel-based electricity prices will be stable over the next 25 years? This would seem to be an unlikely scenario when looking at growing concerns about climate change, Asia’s rapidly increasing energy demands, international political instability, and anticipated uncertainties about the easy exploration of oil reserves.

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Payback of Solar Energy Systems

2009-04-21T18:24:00.001+05:30

A customer investing in a solar PV system should understand the economic payback on his or her investment, even if there may be strong non-economic (e.g. environmental) factors driving the purchasing decision.

The initial investment depends on the system size. A convenient factor that takes this into account is the price per peak Watt (Wp) of the system. Hence, a 2000 Watt peak (2kWp) solar energy system costing $16000 in total (i.e. including installation) will correspond to a price of $8/Wp. In some countries, you may be able to obtain a grant or rebate towards the cost of the system, which will obviously improve the economic payback on the purchase.

You may have different options to finance the purchase, but each of them has a cost. If you are investing cash then you lose its future interest; if you borrow the money then you pay a financing cost. Either way, there is a cost of financing the purchase that can be represented by a so-called "discount rate". The normal cost of borrowing may be reduced if local banks offer low interest loans for the purchase of solar PV systems. Alternatively, your bank might allow you to extend your home loan or mortgage; this may be the cheapest form of standard borrowing.

The economic return on your investment is the value of the electricity that you generate. This will, as a minimum, displace electricity that you would have otherwise bought from your utility or energy service provider during the day. Through certain schemes, it may be separately metered and rewarded at a defined rate (possibly related to the domestic tariff or set by a national or state program). Market incentive programs in certain countries offer some or all of the range of benefits from grants or rebates and low-interest loans to preferential electricity purchase rates. Your local Retailer (also known as "dealer") should be able to advise if any incentives are available to you.

The following graph shows the impact of the solar system price on the payback time of the purchase as a function of the value of the electricity generated, using a discount rate of 5%. As you would expect: the cheaper the Solar System, the faster the economic payback. The higher your regular electricity rate (shown on the bottom axis), the faster the payback on your Solar Energy System.

For example, if your average electricity rate is 20 US cents per kilowatt hour and your installed cost was $4 per Watt (this is achievable where government or utility programs are available), your payback time will be just over 15 years. If you are exposed to peak pricing on electricity rates, take account of tax incentives (available for Corporate purchasers), payback closer to 10 years is reasonable.

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Solar Energy Businesses in the World

2009-04-21T18:19:00.001+05:30

Here you can find solar energy business oppurtunities throughout the world..

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U.S. Energy Investment Services

2009-03-28T20:19:00.001+05:30

The prospects for excellent returns from a direct investment in domestic wells are the best in many years with annual returns exceeding all time highs.

U.S. Energy Investment Services will send you information regarding the strongest performing direct investment opportunities with the finest established domestic oil and gas producers, currently seeking investors for direct participation in multiple oil well and gas programs in proven domestic oil and gas fields, this includes Green Fuel and other alternative fuel solutions.

U.S. Energy Investment Services will send you details on the finest established U.S. Oil and Gas firms, with proven track records of drilled successful producing Oil and Gas wells all over the USA. Fill out the Energy Investor Evaluation to receive details about these firms current direct participation opportunities.

Tax Incentives
Under the current tax code, the most favored investment is drilling for oil and gas. Development of natural gas and oil from domestic reserves helps to make our country more self sufficient by reducing our dependence on foreign imports so Congress provides tax incentives to stimulate this production by private sources. Many investments, which were previously thought of as tax shelters were reclassified under the Tax Reform Act of 1986 as “passive” activities (a business in which the taxpayer does not actively participate). The significant exception to this rule is drilling for oil and natural gas. It is specifically stated as NOT being a passive activity.

So what does this mean to you?

It means that as an investor in oil and gas drilling, one would have significant tax write offs. The first and largest write off is the Intangible Drilling Costs (IDC). Intangible Drilling Costs are expenses that are incurred during the drilling and developing of a well such as labor, testing, geological studies etc. Equipment, however, is excluded, as it is tangible. Usually 70-80% of the investment pays for intangible drilling costs and these can be written off in the year that they occur. Tangible Costs include well equipment and is depreciated over a 7 year period.

As each project and each company is structured differently, please see your personal tax advisors to see how these apply to your particular situation.

India close to solar energy breakthrough

2009-03-28T20:12:00.000+05:30

SOLAR cells used to tap energy from the sun are made up of photovoltaic substances such as silicon which, when combined with suitable additives and exposed to sunlight, produce electricity. Extracting crystalline silicon from the compounds in which it is found is highly energy-intensive and the element itself accounts for upto 50 per cent of the total cost of producing photovoltaic systems. Crystalline silicon for photovoltaic applications costs about Rs 1500 (US $50) per kg in the global market. A little over 25 gms of monocrystalline wafers is required to produce one watt of electricity.

Amorphous silicon has a lower silicon content and costs half as much as crystalline silicon to produce because of its non-crystalline form. The Japanese have extensively used amorphous silicon cells in solar-powered calculators and watches.

The Department of Non-conventional Energy Sources (DNES) has been exploring the use of amorphous silicon technology to reduce the cost of photovoltaic solar cells. Bharat Heavy Electricals Limited (BHEL), Bangalore division, was assigned the task of establishing a plant to produce amorphous silicon solar cells and set up one at Gurgaon, Haryana, which was commissioned in July 1992. The Rs 16-crore plant produces amorphous silicon solar cells equivalent to 500 kwp (kilowatt peak output of electricity) per shift and has an annual capacity to produce 300 kg of Silane gas, an essential raw material. During pre-commissioning runs, the plant produced over 2000 modules of solar cells with different process parameters. Efficiencies of converting solar energy into electricity exceeding 7 per cent were achieved on individual cells in the modules.

According to R K D Shah, Executive Director (corporate planning and development), BHEL, "At present the production of amorphous silicon photovoltaic cells is still in an experimental stage. Though the potential applications are many, amorphous silicon cells are still being tested and tried in various systems and applications."

Scientists at BHEL say that amorphous silicon cells have half the efficiency of crystalline silicon cells but they cost less than half as much. According to Praveen Saxena, principal scientific officer, DNES, the cost of monocrystalline silicon, used in large-scale applications, is about Rs 225 per watt, while that of amorphous silicon, as yet used only in small systems, is Rs 150 per watt. According to BHEL sources, amorphous silicon cells produced in very large quantities can bring down the cost of solar panels to Rs 60 per peak watt.

Research in India has focused on increasing the efficiency of amorphous silicon, which is also unstable and loses efficiency at high temperatures.

Efficiency levels of over 12 per cent have been achieved by the Bangalore unit of BHEL. It has produced solar cells of 10 cm diameter which have achieved upto 14.3 per cent efficiency -- the highest achieved in the country so far. The conversion efficiency of photovoltaic devices in the international market is around 17.5 per cent.

Work on photovoltaic solar cells began in India as early as October 1980, when the Central Electronics Limited, Sahibabad, was established to produce monocrystalline silicon cells.

A separate technology mission was, therefore, set up for the development of amorphous silicon technology in the seventh plan. Prime Minister P V Narasimha Rao, who has taken particular interest in solar energy development, asserted in Parliament, "We are at the point of achieving a breakthrough in commercial applications of photovoltaic technology."

S Mehrotra, an official at BHEL, says, "When we started working on the amorphous silicon technology, we were perhaps 15 to 20 years behind the developed countries. But now we have definitely closed the gap."

Source

Green Mountain Coffee Roasters going solar

2009-03-02T20:12:00.001+05:30

WATERBURY, Vt.—Green Mountain Coffee Roasters is hoping to cut its electric bill with a major solar power installation set for spring.

The Waterbury-based company plans to put 530 solar panels on top of its distribution center in a partnership with Green Mountain Power Corp., and White River Junction-based groSolar.

The project is expected to produce electricity equivalent to what it takes to run 16 houses year-round.

Paul Comey, the coffee roaster's vice president of environmental affairs, says the company sometimes draws up to a megawatt of electricity.

The project is getting helped along by a $250,000 grant from the state's Clean Energy Development Fund.

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Information from: WCAX-TV, http://www.wcax.com

The Best Wind Energy Companies

2008-11-28T20:34:00.001+05:30

The Wind Energy Industry

First, let’s get a quick rundown of the growth of the domestic and international wind markets out of the way.

Here’s the chart for wind power capacity growth by year:

As you can see, global installed capacity for wind energy has grown 482% over the last seven years, from 14,604 MW in 2000 to 84,934 MW in 2007.

Broken down further, the international wind industry has a compounded annual growth rate (CAGR or year-over-year) of 28.6%, which is impressive, to say the least.

But the past performance of the wind energy stocks is going to do little to help the future performance of your portfolio, apart from establishing an historic trend and highlighting what you’ve been missing.

So here’s the global wind energy installed capacity forecast, going out to 2012:

This data reveals that the industry will grow 215% between 2007 and 2012, from 84,934 MW to 267,837 MW. That’s a CAGR of 25.8%

Now this is information that can give your portfolio a boost. In an industry that’s doubling in size every four years or less, there are surely more than a few companies worthy of investment operating within it.

The only thing left to do is to actively seek out the best ones.

To start the search, it’s probably worth taking a look at the countries currently boasting the highest year-over-year growth in the wind industry. So here they are, along with their respective annual growth rates, as provided by GlobalData:

Turkey, 95.4%
Mexico, 84.7%
Brazil, 61%
China, 54%
Poland, 50.9%

Of course, those are the fastest growing markets. According to GlobalData, the largest markets by megawatt capacity are:

China, 51,200 MW
U.S, 45,454 MW
Spain, 36,715 MW
Germany, 35,829 MW
India, 25,935 MW

The only thing left to do is single out the largest operators in those areas, invest, and reap the profits.

Solar Power Wins Enthusiasts but Not Money

2008-11-15T16:55:00.002+05:30

The trade association for the nuclear power industry recently asked 1,000 Americans what energy source they thought would be used most for generating electricity in 15 years. The top choice? Not nuclear plants, or coal or natural gas. The winner was the sun, cited by 27 percent of those polled.

Multimedia

Solar Energy Now and in the Future

Energy Research

It is no wonder solar power has captured the public imagination. Panels that convert sunlight to electricity are winning supporters around the world — from Europe, where gleaming arrays cloak skyscrapers and farmers’ fields, to Wall Street, where stock offerings for panel makers have had a great ride, to California, where Gov. Arnold Schwarzenegger’s “Million Solar Roofs” initiative is promoted as building a homegrown industry and fighting global warming.

But for all the enthusiasm about harvesting sunlight, some of the most ardent experts and investors say that moving this energy source from niche to mainstream — last year it provided less than 0.01 percent of the country’s electricity supply — is unlikely without significant technological breakthroughs. And given the current scale of research in private and government laboratories, that is not expected to happen anytime soon.

The Awesome Solar Tower of Seville

2008-11-15T16:43:00.000+05:30

Located in the Andalusian countryside of Southern Spain, near Seville, is a giant 115 meter high concrete tower surrounded by a field of 624 huge mirrors. These mirrors collect the sunlight and focus it at the top of the concrete tower, where it heats water passing through pipes, converting it into steam. This steam drives a series of turbines that produce electricity. Simple, efficient, environment friendly and spectacular!

These 624 parabolic mirrors each having a surface area of 120m² are heliostats, that track the sun throughout the year, precisely focusing the sunlight to the top of the tower at all times. The temperature at the top rises to over 400'C (750'F).

The current capacity of the Solar Tower is 11MW. The plant when completed in 2013, will produce around 300MW – energy enough for 180,000 homes, equivalent to the needs of the city of Seville, and saving 600,000 tonnes of annual carbon dioxide emissions. We urgently need more of these. - Original Source

5 Powerful Reasons To Invest Into Solar Panels and Save Money!

2008-10-30T00:31:00.002+05:30

Save Money With Solar Panels

So 2008 is winding down and many things have happened this year. Recently the particle accelerator (Large Hadron Collider) was fired up and Barack Obama made young people everywhere have faith in politics.

But the real theme of 2008 has been gas prices. Many people everywhere are still wondering whether gas prices are going to get any cheaper. The reality is that, it will never get cheaper. That's right - never. Not only will gas never get cheaper, but everything we pay for that relies on petrochemicals for production - that is - everything you use - from your chair, computer, desk, plastics, vehicles - will never get cheaper.

Just think about that for a moment - everything that you rely on takes a source of energy that is quickly depleting. It takes many different refined sources of oil (petrochemicals) to manufacture pretty much all the goods and technology we enjoy in abundance. Some argue we have 20 years left, some argue we have 50 - the bottom line is there is a time line within most of our lifetimes.

Let's take a look at your home or apartment for a moment.

Depending on your location, your home is tied into a vast energy grid that is powered by things such as Hydroelectric dams to coal power plants. All of these take petrochemicals to maintain and construct as well.

My main point here is that, as a globe we need to begin changing our energy infrastructure while we have the oil to do it. Don't sweat though, the power is actually in your hands. So while we have this black gold available, we're still able to manufacture such things as solar panels to empower people to get off the grid.

Solar panels are pretty new, but have been around in theory for many many years. If you're a home owner, or even live in a small apartment - a solar panel can help you save money in the long run. But why should you invest besides reasons such as a lack of oil resources?

Here's 5 reasons why you should:

Reason #1 - Durability & Longevity

On average, a solar panel can last up to 30 years or more. With just a few arrays set up, you can be powering your home with your own renewable energy. Not only that, but solar panels are designed to withstand harsh climates. One common misconception is that you need the sun shining to convert to electricity. Solar panels can still convert from solar energy to electrical or thermal power even on a cloudy day (although not at the same capacity).

Reason #2 - Unlimited Power!

While everyone else is crying and whining about gas prices and high energy costs - you will have an unlimited supply of solar power. Unless the sun blows up and destroys our entire solar system - you won't really need to worry about never having power.

Reason #3 - Tax Incentives

Once you invest into solar, you are eligible for Federal, State, Provincial And Utility Tax incentives and rebates. These aren't the '$30 off' from your coffee maker rebates - they add up big time! For example, in Australia, if you spend $16,000 on a solar set up, they will rebate you up to $8000 back. This doesn't include other rebates you can get either. You'll need to check your own country's government policies - but, in the next 5-10 years - all countries will be jumping on the solar bandwagon.

Reason #4 - Not Just A 'One Time' Set Up + Easy Installation

With solar, you don't need to invest into a bunch of costly arrays right away. You're able to set up one panel at a time, and add additional panels whenever you feel the time is right. Furthermore, installing a solar panel is actually quite a lot easier than people think. You can do it yourself, or have an installer come and have it set up for you the same day.

Reason #5 - Add A 'Capacitor' And You Are Laughing + No More 'Blackouts'

A capacitor is a device that lets you store unused energy. So if you're over producing solar energy - usually two things happen. You can either give that energy back into the system grid (that is, pooling your energy into the grid for other people in your community to use) or you can store it in a capacitor. If you were ever to run out of energy, or you are seeing 'under production' - a capacitor lets you have energy that you stored previously. This means you will always have a back up of energy in a time of crisis.

What this also means (and having solar in general) is that when the system grid goes over its maximum energy potential (that is, too much energy is being used in the city which causes a blackout) - you will still be powered up! Your neighbors will be looking in jealousy at the one shiny house in the block.

So there you have it. If you're still not convinced - check out http://solar.envirohub.net for more information.

Top 5 countries to invest in renewable energy

2008-10-20T20:04:00.001+05:30

According to the Ernst & Young 'Renewable Energy Country Attractiveness Index', the 5 most attractive countries for investment are

Spain
USA
Germany
UK
India

in that order. The index provides an overall score for renewable technologies that are currently entering the market on a large scale, i.e. wind, solar and biomass. Wind as the most important renewable from a business perspective today, is weighted 85%, solar and biomass respectively 5% and 10%.

For each technology, an index is constructed based on a mixture of infrastructure and technology factors:

Infrastructure (35%): Market risk, Planning & grid connection issues, Access to finance
Technology (65%): Power offtake attractiveness, Tax climate, Grant/soft loan availability, Market growth potential, Current installed base, Resource quality, Project size

Financial aspects, i.e. access to finance, power offtake attractiveness, tax climate and grants/soft loans, often regarded as the critical factor of success for renewable energy sources, are weighted together 35.5%. They're a very necessary, but far from sufficient condition for development.

Top 5 renewable energy technology in UK

2008-10-20T16:34:00.000+05:30

Renewable energy may make up only a small proportion of the UK’s overall electricity supply, but it is growing. According to the government’s own figures, renewable energy made up 4.55 per cent of all electricity generated in the UK in 2006, which is 0.32 per cent higher than in 2005, and nearly a whole percentage point ahead of the 2004 figure.

That 4.55 per cent makes up 18,133 gigawatt hours (GWh) of electricity generated, an increase of 7.5 per cent compared to 2005. It may sound like a lot, but greater London alone consumed around 41,436GWh of electricity in 2005. And the big guns are still coal (which produces 33 per cent of the UK’s electricity), nuclear (20 per cent) and gas (a whopping 40 per cent).

Renewable energy is measured in megawatt-electrical (MWe), the amount of electrical power a plant has the capacity to produce. For renewables, of course, power capacity doesn’t always equate to how much power is actually produced — wind turbines, for example, only produce power when there is wind. Nevertheless, the UK’s current renewables capacity is 5,659MWe. The UK’s entire electricity power capacity — including coal, gas and nuclear power stations — is 83,045MWe.

The UK still lags well behind other countries in renewable energy generation. In Spain over a weekend in March, according to the AEE (Spanish Wind Energy Association), wind power accounted for an average of 28 per cent of Spain’s entire power demand. But renewables are growing and will continue to do so, as necessity dictates. To shed some light on the use of renewable technologies for electricity production, we’ve looked at the UK’s top five renewables — in no particular order — in terms of total installed capacity and future potential.

Photovoltaic solar panels
The final major renewable energy technology in the UK is photovoltaics solar panels (PV), which currently contribute 12MWe of the UK total electricity capacity. Many installations are on schools and office buildings, but some are being offered directly to consumers by house builders, as with the in Reading. Photovoltaics are growing rapidly, with 2.4MWe of this capacity having become operational since January 2007. Much of that growth was driven by a government funding programme that is now complete, which offered grants for small, medium and large-scale implementations. Whether this growth will continue is a moot point as the government’s successor programme has been criticised by Friends of the Earth for failing to offer consumers enough funding.

Wind
Wind power has massive potential in the UK with offshore wind farms alone apparently able to meet all of the UK’s current electricity needs, according to the government’s figures. Onshore facilities, however, are easier to build and 327 wind farms currently make up 1,842MWe of the UK’s electrical power capacity, according to statistics from the RESTATS database. Wind turbines are more difficult and expensive to install at sea and such make up a more modest 394MWe, but offshore wind farms have fewer planning issues and 90MWe of new capacity has become operational since January 2007. There are currently seven operational offshore wind farms in the UK with a further five under construction.

Hydroelectric
These plants can be divided into large (producing over 5MWe) and small (below 5MWe) hydroelectric plants. Most of the large plants are concentrated in Scotland and Wales and draw their water from high-level reservoirs with their own natural catchment areas, and make up 1,369MWe of energy capacity. Opportunities to grow large hydro capacity are very limited as most of the potential sites are already in use. Smaller-scale plants are growing in popularity and are typically used for domestic or small business purposes and make up 156MWe.

Biofuels
There are many different kinds of biofuels in use for electricity generation, such as the oats-powered plant used by Quaker Oats. Landfill gas is one of the fastest-growing areas — it is the methane-rich biogas formed by the decomposition of organic matter in landfill and can be used to fuel electricity turbines or directly in boilers. RESTAT estimates that this makes up some 875MWe of electricity capacity. Another growing area is sewage sludge digestion, which uses the gas produced to maintain the temperature necessary for the process. This makes up 122MWe with the excess energy being sold off onto the grid. The final growth area is municipal solid waste, which is produced in incinerators and makes up 327MWe of energy capacity. At the end of 2006, there were 24 such plants in operation burning municipal solid waste (MSW), refuse derived fuel (RDF) and general industrial waste (GIW). Other biomass generation projects include Lockerbie’s plant powered mainly by forestry waste, and a straw-fired power station near Ely, Cambridgeshire.

Wave and tidal stream
Being an island at the edge of the Atlantic Ocean makes the UK well-suited for wave and tidal power, but the difficulty in harnessing this means that it so far contributes just 0.5MWe of total energy capacity. The Limpet oscillating water column is the only wave device in the UK. It is located off the isle of Islay in Scotland and is operated by Wavegen. Tidal energy is estimated to have the potential to produce up to 22,000GWh per year, but current deployments are still only prototypes. The government has launched a couple of schemes to encourage wave and tidal plants, but these are not expected to amount to more than around 25MWe of capacity in total, the majority of which will come on stream after 2010.

Original Source: The Smart Planet

Poor nations rich in renewable energy potential

2008-10-15T20:41:00.002+05:30

Developing nations have the potential to generate large amounts of energy from renewable sources, according to a US$10 million assessment coordinated by the United Nations Environment Programme (UNEP).

UNEP hopes to attract support to enable developing countries to transform the assessment's findings into effective energy policies.

The initial results of the Solar and Wind Energy Resource Assessment (SWERA), which looked at 13 developing countries, were announced last week (14 April).

They show how developing countries could harness thousands of megawatts of electricity from solar and wind energy.

"In developing countries all over the world we have removed some of the uncertainty about the size and intensity of the solar and wind resource," said Klaus Toepfer, executive director of UNEP last week.

"These countries need greatly expanded energy services to help in the fight against poverty and to power sustainable development. SWERA offers them the technical and policy assistance to capture the potential that renewable energy can offer."

The SWERA project used satellites and ground-based instruments to assess the potential for wind and solar-powered renewable energy.

Its findings have generated a range of tools to promote the implementation of policies that promote use of renewable energy sources. These tools include maps of wind and solar resources.

The researchers created the 'geospatial toolkit' to overlay wind and solar maps with electricity distribution grids.

Already, the project has influenced policy in several countries, including Nicaragua and Guatemala.

In Nicaragua, the SWERA assessment showed that there was much more potential for wind energy production than was previously thought.

As a result, the Nicaraguan National Assembly passed a decree in 2004 giving wind energy priority over other forms of energy when feeding into the electricity grid.

In Guatemala, estimates that renewable energies could yield 7,000 megawatts of electricity prompted the Ministry of Energy to create the Centre for Renewable Energy and Investment. The centre will identify sites for wind energy development.

According to previous UNEP estimates, the African continent needs 40,000 megawatts of electricity to power its industrialisation. An initial SWERA assessment in Ghana suggests that the nation has the potential to generate more than 2,000 megawatts from wind energy.

It takes about 1,000 megawatts to power a US city the size of Seattle, whose population is 560,000.

Tom Hamlin, project manager for SWERA, said last week that the project will be seeking support to meet requests from renewable energy development programmes in other developing countries.

The 13 developing nations involved in SWERA are Bangladesh, Brazil, China, Cuba, El Salvador, Ethiopia, Ghana, Guatemala, Honduras, Kenya, Nepal, Nicaragua, and Sri Lanka.

See complete article

Top Ten Cost-effective Renewable Energy Systems

2008-10-12T13:58:00.001+05:30

1. A solar thermal system to heat your hot water pays for itself in two to three years depending on your location.
2. A solar water heating system for your pool or hot tub also pays for itself in two to three years.
3. Solar photovoltaics to power your home or business, using government incentives, will reduce your monthly electricity costs significantly, in some areas. In some countries, such as Japan, solar is a viable alternative to fossil fuels. In North America, fossil fuels will continue to rise in cost and solar will continue to decline.

4. A portable solar system for an RV will cost less than a thousand dollars and provide you with power for many years.

5. Solar panels for remote electricity (electric fence, lights, monitoring station, etc.) are much cheaper than hooking up to the grid.
6. A solar photovoltaic system for your cottage or remote location can cost much less than connection to the grid.
7. A geothermal system will pay for itself in five years or less and provide you with heat energy for the lifetime of your home or business.
8. A backup power system to cover your essential electricity needs, when a power outage strikes.
9. A wind energy system to power your farm, home or cottage could make your farm energy self-sufficient, in some geographical areas.
10. A micro hydro power station can provide you with limitless energy, if you have running water on your property.

Top Ten Important Solar Energy Power Tips

2008-10-12T13:55:00.000+05:30

1. Whatever solar power system or product you plan to utilize, always ensure that the solar panel faces in the direction of the sun. In the Northern hemisphere the panel must face south and at an angle to the horizontal equal to your latitude plus 15º.

2. Before meeting a consultant regarding the installation of a solar power system, always have on hand a list of all your electrical appliances together with their wattage and the hours of use. Any dealer worth his salt will need to know this information.

3. Before committing to a specific power system always check to find out exactly what the local, state and federal incentives are in your town. All this information can be found at the DSIRE (Database of State Incentives for Renewable Energy) database at http://www.dsireusa.org/

4. Always have a local licensed installer put in your system (but make sure he has experience with Grid connected systems) - they know all the local regulations and will be able to give you valuable information regarding these rules.

5. Keep solar panels clean - even if it means getting up onto your roof once a month. A thin layer of dust or dirt on the glass cover will effectively block off some solar power and the system will operate below its maximum efficiency.

6. When calculating the number of panels you need, do so using winter sunshine hours rather than summer hours - there are roughly twice as many hours sunshine in summer and the wrong calculation could leave you needing to use backup power in winter more often than you would like.

7. In any solar system keep your panels as close as you can to the batteries to avoid losing power in the cable. Always make sure that your panels are not shaded.

8. When planning a solar heating system, always consider the use of solar shades or smart glass to augment your system - their use can save you a lot of energy that might otherwise escape from the house.

9. Many states organize tours of homes that are fully converted to solar. Try to get yourself on one of these tours so that you can see a solar home in its working state.

10.Before installing a solar system try to make your home as energy efficient as possible - install double glazing, add new insulation where possible, replace incandescent light globes with fluorescent etc. By reducing your needs you can reduce the size and cost of the system you're installing.

Benefits of Going Solar

2008-10-10T21:19:00.000+05:30

Why have over 1.5 million Americans invested in solar? Surveys taken over the last ten years confirm that the vast majority of owners (94% or more) consider that investment a wise decision. Consumer investment and satisfaction have spawned a small but growing solar hot water (SHW) industry here in the U. S. that is providing even broader benefits to our nation and has the potential to contribute much more.
Clean and Safe Solar hot water systems in use today produce approximately 1000 megawatts of energy annually. That is the equivalent of two medium-sized coal plants. The life-cycle costs of SHW systems are about the same as gas and far better than electric water heating systems. Solar energy is pollution-free, an important benefit when the cost of removing pollutants from the environment is considered. For example, a typical SWH system will, over its lifetime, displace 10.5tons of CO₂if replacing a natural gas system, or 71.5 tons if replacing an electric system.

Readily Available Resource The U. S. Department of Energy estimates that Americans consume approximately 2.5 quads of end-use energy annually to produce hot water at a cost of over $20 billion dollars. Solar energy currently provides only a tiny fraction of that demand, but huge portions of our country possess sufficient insolation to produce much greater quantities of energy. Enough sunlight reaches the earth’s surface each yearto produce approximately 1000 times the same amount of energy produced by burning all fossil fuels mined and extracted during the same period. Sunlight does not have to be explored, mined, extracted, transported, combusted, transmitted — or imported. Quality, Reliability, Durability Solar water heating technology, pioneered in the U. S., is the oldest and most developed of all renewable energy systems. Modern solar water heating systems can provide a large portion (40 - 80%) of household hot water demand depending on local climate conditions and the size and type of system. Most systems pay for themselves in four to sevenyears and continue to provide hot water for many years thereafter.
	Much of the United States receives abundant sunshine, making solar hot watersystems a very economical investment. This map shows the average daily solar radiation available on a south-facing surface measured in megajoules per square meter each day.

Solar pool heating often provides an even better investment. Payback can be as low as two years and the solar system can extend the swimming season by several weeks without additional cost. Many homeowners have regretted the purchase of a conventional pool heating system after receiving their first utility bill. Another cost-efficient application for solar energy is preheating ventilation air for commercial and industrial facilities. The vast majority of U. S. manufacturers of solar equip ment voluntarily comply with national consensus standards devel oped by the Solar Rating and Certification Corporation (SRCC). The SRCC tests and certifies collectors as well as complete systems for performance, reliability and durability. In addition, manufacturers and installers comply with the SRCC’s strict requirements for proper installation, labeling and homeowner information regarding operation and maintenance. Assurances of performance and quality are backed by warranties that in many cases exceed the guarantees of other household appliances. Read Complete Article

China Plans for 30% Renewable Energy by 2050

2008-10-10T21:08:00.000+05:30

In the June 2007 issue of the China Renewable Energy and Sustainable Development Report from Lou Schwartz, recent developments in renewable energies in China offer insight into that country's burgeoning challenges between population, energy and the environment.

"Between 2005 and 2030, China will account for 23% of the world's investment in power, spending $1.2 trillion U.S.D. in that period."

-- China Renewable Energy and Sustainable Development Report, June 2007

The report cites that the "Persistent rural poverty in China and periodic power shortages all have impressed upon Beijing that renewable energy must be a large part of China's economy if China is to both complete its economic transformation and achieve energy security."

"Between 2005 and 2030, China will account for 23% of the world's investment in power, spending $1.2 trillion U.S.D. in that period," Schwartz notes. "China's ambitious growth target for renewable energy production will require an investment of approximately 800 billion Yuan (~$100 billion U.S.D.) by 2020. In the long term China has set an objective of having 30% or more of its total energy requirements satisfied by renewable sources by 2050."

Current business opportunities, foreign participation, relevant conferences, and production and consumption are also discussed in this month's China Renewable Energy and Sustainable Development Report.

The in-depth report examines developments across China's renewable energy industry, as seen in these excerpts:

- Solar: "The Chinese government has recently announced that large new buildings will all utilize photovoltaic power generating technology."
- Wind: "Researchers at the Jiangsu Province Macroeconomic Research Institute have advocated that large-scale wind power should be directly used to provide electric power to industries, which are large consumers of power."
- Hydropower: "In 2007 there will be another 500 MW of small to medium sized hydroelectric power generating capacity constructed in Guangxi Province."
- Biomass, Biofuels: "China hasn't yet standardized its macro-economic policies with respect to the bio-diesel industry, but it is now formulating and will soon..."
- Laws and Policies: "These sets of issues include the fact that there are more than 10 million Chinese who do not have access to electric power and the often-spotty access to power among tens of millions of other rural Chinese."

Read Full Article

Renewable energy alone can save India

2008-10-08T20:50:00.000+05:30

Dr Prodipto Ghosh, former secretary in the ministry of environment and forests, currently a special energy adviser with The Energy and Resources Institute (TERI), believes the future lies in developing renewable forms of energy.

Dr Ghosh, who played a key role in penning the recently released PMO report on climate change, believes: "Renewable forms of energy, including solar, wind and tidal, must be mainstreamed in order that they can substantially displace oil, gas and coal. Many renewable forms are already being used in niche applications such as street signalling, remote area power supply and village homes."

This turnaround can be best illustrated by the example of wind power. Thirty-five years ago, when the world began to look at wind power, it needed a great deal of government support. In the late 90s, when the global capacity of wind energy was increased to 65,000 megawatts, it became competitive with coal.

Since India receives a great deal of sunshine, the key question is how to make solar energy commercially viable, especially since only one per cent of India’s landmass would be required by solar PVs to meet our electricity needs. Dr Ghosh agrees but states, "A great deal of R&D is required to bring solar energy costs down. A strong government commitment to R&D, matched by an increasing scale of technology, will help kickstart this change."

Read the full article

Dell Headquarters Uses 100% Renewable Energy

2008-10-07T19:58:00.000+05:30

As of April 2, Round Rock, Texas-based Dell is powering 100 percent of its 2.1 million square-foot global headquarters campus with 100 percent green power.

"It's time for our industry to take a lead role in creating a clean energy future," said Paul Bell, president, Dell Americas. "We are challenging every technology company to work with their suppliers and partners in integrating green power and energy-efficient strategies into their operations."

Dell is using all of the power generated from Waste Management's Austin Community Landfill gas-to-energy plant, meeting 40 percent of Dell headquarters’ campus power needs. The remaining 60 percent comes from existing wind farms and is provided by TXU Energy.

The computer company also announced it is increasing green power use for its Austin Parmer Campus, provided by Austin Energy, from 8 percent to 17 percent. Dell also is powering its Twin Falls, Idaho, facility with 100 percent green power, 97 percent of which is wind power and 3 percent solar.

In September 2007, Dell announced it would make company owned and leased facilities "carbon neutral" in 2008 through a strategy of improving energy-efficiency in its operations and maximizing the purchase of renewable power. This commitment is part of the company's climate strategy which also seeks to minimize carbon impact of supplier operations and customer product use.

Read the full article

Top 10 US Cities for Renewable Energy

2008-10-07T19:54:00.001+05:30

Top Ten US City Use of Renewable Energy

data table
table header row 1	table header row 2	table header row 3
1.	Oakland, CA	(17%)
2.	Sacramento/SF/San Jose, CA	(12%)*
3.	Portland, OR	(10%)
4.	Boston	(8.6%)
5.	San Diego, CA	(8%)
6.	Austin, TX	(6%)
7.	Los Angeles, CA	(5%)
8.	Minneapolis, MN	(4.5%)
9.	Seattle, WA	(3.5%)
10.	Chicago, IL	(2.5%)

Which of the largest 50 US cities provide citizens with the highest percentage of power produced from renewable energy? SustainLane Government (www.sustainlane.us) determined the percentage of each city’s electricity that comes from renewables such as solar, wind, geothermal, and small-scale hydro energy.

Renewable energy sources produce electricity with no global climate-changing greenhouse gas emissions or regional air pollution that comes from burning fossil fuels such as coal and natural gas. Renewable energy technologies also produce regional jobs while limiting the importation of energy from other nations.

Just over 33 percent of greenhouse gases produced in the United States came from electricity production in 2004, making it the leading category of such emissions over other areas such as transportation (27.9 percent), industry (19.6 percent) and agriculture (7 percent).

The leading cities in renewable energy could have an advantage in any upcoming federal or state regulations aimed at regulating or eliminating greenhouse gas emissions or developing renewable energy standards. If the greenhouse gases that cause climate change get priced, cities with strong renewable energy programs could save a lot of money in the long run and their economies could gain a tax advantage.

Oakland, California led the nation with 17 percent of its electricity being produced by energy sources such as solar, wind and geothermal energy. Oakland gets some of its wind energy power from one of the largest wind power generating facilities in the nation at nearby Altamont Pass.

San Francisco, Sacramento and San Jose tied for second with 12 percent of their electricity coming from renewable energy sources.

California cities rank high in general because of the state’s Renewable Portfolio Standard, which set minimal requirements in 2002 for utility purchases of renewable energy for the state’s electric grid. That standard requires a 20 percent renewable energy total for the state’s utilities by 2020.

Some U.S. cities have also set goals for increasing renewable energy ranging from Chicago’s 20 percent goal by 2010, to Portland, Oregon’s goal of obtaining 100 percent renewable energy by 2010.

Renewable energy made from waste

2008-10-05T12:45:00.001+05:30

A company in Swindon has developed technology which it claims turns household rubbish into clean renewable energy.

A company in Wiltshire has claimed it is one of the first in the UK to turn household rubbish into clean renewable energy using "gas plasma technology".

Advanced Plasma Power (APP) said its small-scale plant in Swindon sends less than 1% of waste back to landfill.

The process uses a beam of electrified gas at temperatures approaching 10,000C to destroy waste turning it into a flammable gas generating electricity.

It hopes to create jobs around the new technology developed in Swindon.

'Electricity generated'

Andrew Hamilton, of APP, said: "We see great potential to develop and exploit the technology for the benefit of not only us but we hope it will create substantial jobs in the area."

Dr Tim Johnson, of APP, said: "The reality is, that if waste is not turned into a fuel like this then it would have to go to landfill, so we're diverting material from landfill to make fuel."

The process is called "plasma gasification" - all recyclable materials such as glass and metals are removed and the remaining waste is then transformed into a hydrogen-rich gas. When the gas is then burned in the reactor electricity is generated.

APP claims that a full-scale plant could process 50,000 tonnes of waste annually.

Storage Boosts the Power of Renewable Energy

2008-10-05T12:39:00.000+05:30

how to integrate large amounts of renewable energy into the grid was the topic at the recently held Electricity Storage Association's Annual Meeting in California. At the meeting, leading companies, manufacturers, utilities and policy developers gathered under the motto "Electricity Storage: Predictable Power in a Cleantech World."

During the conference experts showed how energy storage can play a variety of roles in firming up renewables at different time scales, i.e. from moment to moment, daily, weekly and seasonally. The presentations showed how storage options are essential for expanding renewable energy sources, stabilizing the grid, ensuring a continuity of supply, increasing energy autonomy and mediating against intermittent power production.

As storage technology advances, decision makers are starting to create a more favorable policy environment for innovators. For example, the U.S. Energy Storage Technology Advancement Act of 2007 recognizes the crucial roles that storage can play.

"This bill is the first official recognition of the importance of energy storage by Congress," said Imre Gyuk, Manager of Energy Storage Systems Research with the Department of Energy. "It is only an authorization bill and thus carries no appropriated funding, but it is a wonderful platform for future requests for storage research, demonstrations and development."

The act establishes an Advisory Committee (the Energy Storage Advisory Council), and authorizes funds for a basic and an applied research program of US $50 million and $80 million, respectively, for each fiscal year from 2009 to 2014. It also provides US $100 million each year for up to four energy storage research centers; US $30 million a year for energy storage demonstration projects and vehicle energy storage demonstration; and US $5 million a year for 10 years for secondary applications of electric drive vehicles.

Reaction to the act has been positive and the storage industry is beginning to take off.

"Grid-scale storage is here now," said Ed Cazalet of MegaWatt Storage Farms. "Storage should be deployed now at the gigawatt (GW) scale...where capacity, ancillary services and energy time-shifting are clearly needed."

Storage projects can be sourced close to loads, on the grid or at the generating facility. In his presentation, Cazalet emphasized that the demand-pull from large-scale commercial deployment will encourage manufacturing investment, lower costs through volume production (economies of scale) and lead to the commercialization of advanced technologies.

Read the full article

Solar Energy Facts

2008-10-01T19:52:00.000+05:30

Our sun is a huge energy generator that provides us with a tremendous quantity of power that mostly goes unused. Solar panels can convert the energy from the sun's rays directly into useable electrical energy. Although the actual method of converting solar radiation into electricity involves a complicated formula that requires an in depth knowledge of physics to understand, just knowing that the solar energy our planet receives can be changed into electricity should be sufficient knowledge to meet most of our needs.

Something that keeps a lot of people from deciding to take the plunge into solar energy is the mistaken idea that solar energy is in some manner a lower quality energy than electricity produced from fossil fuels. In actuality, solar energy's emissions free conversion to electricity makes it an even more beneficial energy source as far as the environment is concerned.

Do you know which country utilizes solar energy to the highest degree? Despite its Northern location far from the equator and its comparatively small population, Germany presently employs more solar energy than any other country. This should dispel any of the misconceptions about solar energy not being a credible energy solution in northern climates.

GLOBAL WARMING AWARENESS

2008-10-01T19:49:00.000+05:30

Global Warming Skeptics - Skeptics of global warming think that global warming is not an ecological trouble.

Global Warming Facts - 8 Facts about Global Warming

Causes of Global Warming - The Green house gases are the main culprits of the global warming. The green house gases like carbon dioxide, methane, and nitrous oxide are playing hazards in the present times.

Green House Gasses are the ingredients of the atmosphere that add to the greenhouse effect.

Al Gore Global Warming Initiative - Gore has written a book that archives his advice that Earth is dashing toward an immensely warmer future.

Global warming is caused by green house gases, which trap in the sun’s infrared rays in the earth’s atmosphere, which in turn heat up the earth’s atmosphere. These green house effect warming is called as global warming. The effects of green house effect are visible more prominently in the recent years, with number of natural calamities on the rise in the whole world.

The global warming has happened in the past few years and is evident from the rise in mean temperature of the earth’s atmosphere. The main causes for the global warming are attributed to release of green house gases by human activities. The main gases contributing to green house effect are carbon dioxide, water vapor, methane and nitrous oxide. The largest producers of these gases are the thermal power plants, which burn the fossil fuels and produce these gases in large quantities. The second biggest sources of these green house gases are the road vehicles and industries.

The global warming has led to increase in mean earth surface temperature and thus melting of polar ice. There are frequent melt down of glaciers that result in floods and other natural calamities. The melting of ice at the poles had led the mean sea level. And further increase in temperature may further melt the ice and lead to further increase in mean sea level, which will engulf low lying countries.

The effect of global warming is very evident on the animal kingdom also. Some animals have become extinct due to loss of their natural habitat or their inability to evolve to the rapid changes in the climate. Also there is a change in their life style because of the changes in the seasons. The migrating birds have changed their time of travel and also their place of migration.

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Bill Gates Invests $84M on Corn Power

2008-10-01T19:47:00.001+05:30

Bill Gates' investment firm, Cascade Investment, agreed last month to buy 5.25 million preferred shares in Pacific Ethanol, a producer of the corn-based fuel hailed by environmentalists as an answer to the earth's dwindling supply of petroleum. The financing, in which the preferred shares will be converted into common stock, is expected to close in January and will net the Fresno, California-based company $84 million. In an interview at Reuters' Times Square offices, Koehler said Gates' investment was a sign that ethanol can be a viable alternative to oil at a time of see-sawing gasoline prices and concerns about global warming and climate change. Gates' money will help Pacific Ethanol proceed with its plan to initially build five plants on the West Coast to process Midwestern corn into ethanol, he said.

For the full story, use the following link.

Read Full Article

New Methods To Protect Wind Generators During Voltage Dips Developed

2008-09-23T20:18:00.001+05:30

To provide a solution to the problems caused to wind turbines by sudden dips in voltage in a part of the electric grid. This was the objective of industrial engineer and member of INGEPER Research Team at the Public University of Navarre, Jesús López Taberna. The fruit of his research is a rotor model which enables anticipating how the wind power unit will behave in these situations. Mr López has patented two techniques of protection, one of which has already been transferred to a manufacturer who will exploit it at international level. This system allows the generator turbine to remain in operation during these voltage dips and thus prevent the wind energy converter from ceasing to function.

The title of the PhD is: “The behaviour of wind-powered generators with double-fed asynchronous motor during voltage dips”.

Over the past few years, the growth and development of wind energy converters has been slowed by problems that have arisen from the increase in the number of these connected to the electric grid. One of the most important problems is precisely the manner in which the wind generators behave during these voltage dips.

A voltage dip is a sudden reduction in potential in the electric grid, followed by a rapid return to its normal value. This, at times, can be caused by lightening or a tree falling on power cables but also due to a large company consuming a lot of energy in one go. This drop in voltage happens in a matter of milliseconds; “we are aware of it because the lights begin to flicker or because they go off and on momentarily – but, for a machine, this can be an eternity”, explained Mr López. In fact, an interruption of half a second in a productive process can cause the whole process to block and it may have to be reinitiated.

Read Full Article

U.S. Leads World in Wind Energy

2008-09-15T16:55:00.001+05:30

The United States has taken over from previous champion Germany in wind power production. For this USA has to be thankful to nature and human resource that produce technology. Nature has gifted USA with stronger wind than Germany. Randall Swisher, the executive director of the American Wind Energy Association, said that the US wind energy capacity is growing faster than anyplace else. But if we try to view those stats differently, Germany harnesses seven percent of their power from wind and Denmark generates twenty percent of power from wind. Wind energy only constitutes 1.2% of total power consumption in America.

Oilgae - Oil from Algae

2008-08-13T10:19:00.002+05:30

Oilgae Forum

We now have a forum @ Oilgae - see here

if the link above does not work, http://www.oilgae.com/forum

Sections from Oilgae that might be of interest:

Oilgae Blog – A dynamic news & discussion forum for biodiesel production from algae; contribute and join the discussions! See Blog Directory for list of articles.
algOS – We are seriously exploring an Open Source movement for biodiesel from production algae; if you are a biodiesel enthusiast, perhaps you’d like to join algOS, the open source movement for oil from algae?

NewNergy – What’s New in Energy - Energy Inventions & Breakthroughs
Oilgae Energy Portal – alternative & renewable energy, peak oil…
See also: BDPedia – The Biodiesel WWW Encyclopedia; Algae – World of Algae
Oilgae Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q| R| S | T | U | V | W | X | Y | Z|
Oilgae Energy, Alternative Energy, Renewable Energy Research

Venture Capital Investment in Renewable Energy Soars to $3.4 Billion in 2007

2008-08-13T10:13:00.001+05:30

According to newly released data from Greentech Media, Inc.,
venture capital investment in renewable energy reached an
unprecedented level of $3.4 Billion in 2007. Investment in solar power led the VC charge with more than $1.05 Billion invested in more than 70 VC financing rounds. Also winning record amounts of renewable energy funding was investment in battery technology at $433.9 Million and in the energy efficiency/smart grid sector at $419.1 Million. Venture firms continue to invest in biofuels such as cellulosic ethanol and biodiesel, with more than $750 Million directed towards these new feedstocks and technologies.

source Link

Ethiopia powers up with solar energy

2008-08-13T10:11:00.000+05:30

Germany's Solar Energy Foundation aims to improve living conditions and foster a solar industry in Ethiopia.

The rural village of Rema in Ethiopia could become a cleantech boom-town if the work of Germany's Solar Energy Foundation continues its success in the region.

Since 2006, the foundation has installed 2,000 solar systems in Rema and in nearby Rema ena Dire, the biggest solar power project in East Africa. The project has brought power to 5,500 residents in a country where only one percent of people in rural areas have access to electricity.

More from here

SOLAR ENERGY BENEFITS

2008-08-11T00:50:00.000+05:30

Solar energy benefits are limitless making the environmental impact by humans on our planet nearly zero. Solar energy benefits should be examined with regard to you and your family’s quality of life for a number of reasons. I encourage you to note the following list of solar energy benefits:

lower utility costs to you

reliable power in an area where there is no dependable utilities available

dependable power where emergency back-up is needed

do your part to MAKE A DIFFERENCE in our environmental impact of burning coal or oil

a practical project for people interested in the technology as a hobby

creating your own electricity so that you are self-sufficient.

Since each of us purchases electricity from our local utility company it is interesting to note how solar energy benefits can impact your future. Your local utility costs will continue to rise impacted by inflation and the cost to produce the utility itself; you can actually produce your own electricity for less money with its cost actually going down in future and help with our environment as well.

Top 10 Renewable Energy Sites

2008-08-06T19:27:00.000+05:30

Alternative Fuels & Advanced Vehicles Data Center x
This Office of Transportation Technologies site has information on the latest advances in alternative fuels, vehicles, refueling sites, and more.

The American Solar Energy Society x
ASES is a national organization dedicated to advancing the use of solar energy for the benefit of U.S. citizens and the global environment.

American Wind Energy Association x
AWEA advocates the development of wind energy as a reliable, environmentally superior energy alternative in the United States and around the world.

Florida Solar Energy Center x
FSEC is the largest and most active state-supported renewable energy and energy efficiency research, training and certification institute in the United States.

Re-Energy x
Informative and educational site that teaches about various forms of Renewable Energy and then teaches you how to build and use them.

National Alternative Fuels Training Consortium x
NAFTC fosters a clean environment for the benefit of all people through education, training and research dealing with advanced fuels and engine systems.

Renewable Energy Policy Project x
REPP supports the advancement of renewable energy technology through policy research.

Alternative Technology Association x
A non-profit community group that aims to use and promote environmentally friendly technology, including renewable energy sources such as the sun, wind and water; building with natural materials and conserving energy.

CANTEST x
Find information on alternative fuels (propane or LPG, natural gas, hydrogen, methanol, ethanol, biodiesel), hybrid electric vehicles, batteries and fuel cells.

California Energy Commission x
The California Energy Commission is the state's primary energy policy and planning agency, charged with ensuring a reliable and affordable energy supply.

A-Data Solar Disk - Solar Gadgets

2008-08-04T18:47:00.001+05:30

Available in 128MB, 256MB, 512MB, 1GB and 2GB capacities, the A-Data Solar Disk thumb drive sports a solar powered LCD panel which displays the remaining memory capcity.

See Source

Rising Oil Prices Vs Solar Energy

2008-07-30T17:47:00.000+05:30

Rapidly rising oil prices have led to such a demand for solar energy that the industry could operate itself without subsidies in just a few years, according to industry leaders.

At the Munich solar industry trade fair, industry leaders were increasingly confident that grid parity - where electricity from the sun can be produced as cheaply as it can be bought from the grid - is now just a few years away.

Solar photovoltaics (PV), which convert sunlight into electrical power, have long been dismissed as too expensive and not efficient enough to make a meaningful contribution to the battle against climate change.

But costs are falling dramatically as PV production escalates as electricity prices rise rapidly year on year in line with soaring oil and gas prices.

Germany now has nearly half a million houses fitted with PV panels. The feed-in tariff pays people with solar panels above-market rates for selling power back to the grid. Governments around the world might well take notice of the German approach.

With high oil prices have boosting demand even more. The market will probably expand another 40% this year, according to the German solar industry association.

Previous predictions that grid parity would be reached in Germany in 5-7 years, now look very conservative since. Germanys predictions allowed for only a 3% rise in electricity prices each year. In many countries increases of 20% a year are becoming the norm.

The China-based Suntech, the world's biggest maker of PV panels, plans to double production this year.

They believe grid parity in Germany can be reached within 5 years. In California and Italy, where there is lots of sun and high electricity prices, they said grid parity for PV systems had already been achieved.

And the great thing about solar energy is that although you have an upfront cost, the fuel is free and is not controlled by another country.

PV costs are falling rapidly and will continue to do so as the efficiency of panels improve and installation costs drop. Moreover, the price of silicon - which can be 70% of panel costs - is also likely to fall as new production technology becomes available.

See Complete Article

Oil Freedom through Solar Energy

2008-07-23T19:09:00.000+05:30

A massive switch from coal, oil, natural gas and nuclear power plants to solar power plants could supply 69 percent of the

U.S.

’s electricity and 35 percent of its total energy by 2050.

A vast area of photovoltaic cells would have to be erected in the Southwest. Excess daytime energy would be stored as compressed air in underground caverns to be tapped during nighttime hours.

Large solar concentrator power plants would be built as well.

A new direct-current power transmission backbone would deliver solar electricity across the country.

But $420 billion in subsidies from 2011 to 2050 would be required to fund the infrastructure and make it cost-competitive. {That is equivalent to 1 year of military expenditures}

High prices for gasoline and home heating oil are here to stay. The U.S. is at war in the Middle East at least in part to protect its foreign oil interests. And as China, India and other nations rapidly increase their demand for fossil fuels, future fighting over energy looms large. In the meantime, power plants that burn coal, oil and natural gas, as well as vehicles everywhere, continue to pour millions of tons of pollutants and greenhouse gases into the atmosphere annually, threatening the planet.

Well-meaning scientists, engineers, economists and politicians have proposed various steps that could slightly reduce fossil-fuel use and emissions. These steps are not enough. The U.S. needs a bold plan to free itself from fossil fuels. Our analysis convinces us that a massive switch to solar power is the logical answer.

Solar energy’s potential is off the chart. The energy in sunlight striking the earth for 40 minutes is equivalent to global energy consumption for a year. The U.S. is lucky to be endowed with a vast resource; at least 250,000 square miles of land in the Southwest alone are suitable for constructing solar power plants, and that land receives more than 4,500 quadrillion British thermal units (Btu) of solar radiation a year. Converting only 2.5 percent of that radiation into electricity would match the nation’s total energy consumption in 2006.

To convert the country to solar power, huge tracts of land would have to be covered with photovoltaic panels and solar heating troughs. A direct-current (DC) transmission backbone would also have to be erected to send that energy efficiently across the nation.

See Complete Article

Cool Ideas - Solar Energy

2008-07-21T10:08:00.000+05:30

Global Warming is a big issue but the world currently needs oil to run. This can be chnaged if governments and people were willing to switch to alternative methods of energy production such as Solar Energy.

Whats good for the environment is good for business

2008-07-14T11:02:00.001+05:30

Support renewable energy and make world of difference for your business and the environment.

Join more than 15,000 other customers who support the growth of clean, renewable energy and preservation of our environment by participating in Second Nature. You don’t have to change your business to enroll, and it costs as little as $5 a month to make a world of difference.

When your business supports Second Nature, we’re able to buy and use more earth-friendly renewable energy, like wind and solar power, and less non-renewable resources, like coal, natural gas and nuclear.

Calculate your potential environmental impact

Every Second Nature customer helps build the demand for green energy, reduce our dependence on fossil fuels, and strengthen our domestic fuel base.

It’s just good business sense

Your support of renewable energy allows your business to:

Demonstrate a leadership role in your industry
Gain a competitive edge
Add value to your brand and generate positive publicity
Promote socially-responsible business practices and consumer health

As a business customer, you have a unique opportunity to join Alliant Energy’s other business green energy buyers. Nationally, you’ll be among the ranks of companies like 3M, Sprint, Lockheed Martin, Good Earth Natural Foods and Starbucks Corporation in supporting the growth and purchase of green power.

High lubricant Prices will make good for Renewables

2008-07-12T09:41:00.002+05:30

Present high oil prices make life difficult in poorer countries but at the same time also help fuel development of renewable energy sources
There are several dilemmas regarding the high oil price.
It makes it difficult for the poor countries. At the same time renewable energy will be developed faster, which is good.

Higher Oil Prices Make Renewable Energy Living

2008-07-12T09:36:00.002+05:30

Human Beings talk a more about alternative fuels being more Living with oil at such high prices. It also, however, makes other, more exotic, fossil fuel extraction techniques viable. This piece in the UK’s Independent outlines how oil reserves are understated because certain known fields are too expensive to extract at this time - and therefore are excluded from oil reserve projections (an important point that I would wager that many investors don’t understand).

The risk for green investors (and the environment for that matter) is that, if true, tapping oil reserves such as these could grow oil supply over current projections (even if its at these current high prices) - driving out the peak oil scenario longer than anticipated by Wall Street. (This is the kind of stuff investors and analysts miss all the time).

Emerging Oil Prices making Renewable Energy More Powerful

2008-07-11T09:50:00.002+05:30

"Emerging fossil fuel prices are making renewable energy more involving in the global market"

Renewable energy can't offer much relief to drivers and companies seeing their profits evaporate because of skyrocketing oil prices, because viable green alternatives to gasoline are hard to find. Biofuels such as ethanol and biodiesel aren't widely available, and hydrogen-powered cars aren't expected to hit the market for years.

Price curves
But in the electricity market, green power, especially wind, is already competing with traditional sources. At today's average wholesale prices, wind costs 4.2 cents per kilowatt hour, compared with 4 cents for coal, 6.8 cents for natural gas, 9.1 cents for oil and 10 cents for nuclear power, according to Kyle Datta, managing director at the Rocky Mountain Institute, a research group focused on eco-friendly business.

Experts estimate that at today's consumption rates, known global supplies of oil and natural gas would be depleted within decades. But prices are expected to rise significantly long before supplies run out, making those fuels too expensive to use at current levels.

"They're never going to run out, but the ability to match supply to demand may already have run out, especially for oil," said Stephen Leeb, president of Leeb Capital Management and co-author of "The Oil Factor," which predicts that oil could hit $100 a barrel by 2010.

In the short term, fossil fuel prices are being driven up by war, political instability, natural disasters and other variables. The long-term outlook is clearer — global supplies are dwindling as demand soars, particularly in China and India, where automobiles are multiplying and economies are growing a breakneck speed.

"We should treat the prices as a warning that we need to act to promote energy efficiency and renewable energy," said Ralph Cavanagh, an energy expert at the Natural Resources Defense Council. "They represent a terrible threat to the vitality of the United States."

Meanwhile, improving technology, tax credits, low interest rates and government mandates are making renewables more widely available, establishing an inexhaustible energy supply that will keep driving prices down.

Different Kinds of Renewable Energy

2008-07-08T17:14:00.001+05:30

Solar energy which comes from the sun can be turned as electricity and heat. Solar panels on the roofs of houses, building and other establishment are use to store the solar energy. The sun's energy harnessed by the panels runs generators which provide electricity. There are stand-alone solar panels that you can put in your yard to save the sun's energy in a generator.
Geothermal energy is an energy that comes from the heat inside the earth. It's simple technology that involves boring a hole into the ground to take the heat from the earth's crust. The heat that comes off is used to heat water and make steam to power generators to make electricity.
Biomass energy is from the plant and trees. This energy alternative makes use of husks that come off rice after it is harvested and the waste from the corn. This "biomass" can be burned in a power station built for such a purpose. It emits less pollution than if the waste was left to rot, because it would produce a lot of methane.

Sources: Wood (most common source), plants, agricultural waste, industrial waste, even methane gas from community landfills.

Uses: fuel for transportation or to manufacture product that would otherwise use fossil fuels.

Water Energy - the natural evaporation/precipitation cycle makes water a renewable source of energy. The heat of the sun causes water in lakes and ocean to evaporate and form clouds. The water then falls back to earth as rain or snow, and goes to the rivers and streams that flow back to the ocean. Moving water can be used to power water wheels that drive mechanical processes. Water Wheels are useful for generating mechanical energy to grind grain or saw wood, but are not practical for generating electricity because it is bulky and slow. Water energy emits about 30 times less greenhouse gas than modern natural gas power plants and 60 times less than coal-fired plant, which makes it a clean source of energy.
Wind Energy is captured by wind turbines and used to generate electricity. The costs of wind energy are going down as mass manufacture of turbines becomes more accepted. It costs the same as setting up a new coal or nuclear power station. More importantly, external cost to health care and the effects of acid rain are 50times less than when using coal.

Renewable Energy - Benefits

2008-07-08T17:04:00.000+05:30

The most obvious benefits of renewable energy are that it is far less polluting than conventional energy and will not run out. Renewable energy can also be produced more locally. This means that it can help local and national economies by using local resources and creating jobs. It will also help reduce the country’s dependence on overseas countries that may be politically unstable. This will help ensure supply and avoid price fluctuation.

Renewable energy is also much safer than nuclear energy which some people regard as ‘clean’. Accidents in nuclear plants can be catastrophic and there is the added problem of having to deal with nuclear waste.

One of the most important benefits of renewable energy is the fact that it’s non-polluting. And of course as the name tells us it is renewable and does not use resources that can never be replaced. Renewable energy has a much lower environmental impact than conventional sources of energy. But there are other advantages to using renewable sources of energy.

There are many benefits of renewable energy to the ordinary citizen and business owner. Homeowners will reap rewards from using renewable energy and energy-efficient appliances by saving money in the long run and reducing environmental impacts. It also renders us able to fuel our homes independently in many cases. Using renewable fuels makes us less dependent.

Benefits of Renewable Energy Source:

* Renewable energy sources offer clean alternative to fossil fuels.
* RE produces little or no pollution or greenhouse gases.
* RE will never run out

Our Future Energy - Solar

2008-07-05T21:12:00.001+05:30

Great video.. Wow! I didn't know that burning fossil fuels produced pollution!

The lost history of biofuels

2008-07-03T20:29:00.000+05:30

It's surprising that the history of something as important as renewable energy in general, and biofuels in particular, would be so little known. If you read current historical works on energy, there is no mention of ethanol or other biofuels. The Prize or most other histories of the energy have little or no mention of alternatives.

Its like we have a history of Rock and Roll with the Beatles but not the Stones. Or of aviation with the Wrights but not Curtis. Or of dance with Fred but without Ginger.

Before we open a narrative on the history of renewable energy and biofuels and the people who fought for their recognition, we might take a minute to think about history itself.

Thucydides (460 - 400 BC) once said: "The way that most men deal with traditions, even traditions of their own country, is to receive them all alike as they are delivered, without applying any critical test whatever..."

Plenthy of material

To ignore alcohol as a fuel entirely in the history of energy certainly seems fishy. There is plenty of raw material to go on. For example:

At least 152 popular and scholarly articles under the heading "Alcohol as a Fuel" can be found the the Readers Guide to Periodical Literature between 1900 and 1921.
About 20 references to papers and books written before 1925 are found in the Library of Congress database catalog; a 1933 Chemical Foundation report lists 52 references before 1925 on alcohol fuels. A1944 Senate report lists 24 USDA publications on alcohol fuels before 1920. Technical books from the period document hundreds of additional references .
The New York Times database returns 408 results for alcohol and fuel in the 1900 to 1925 time period and 602 in the next 25 years. In the 1951-1975 period the number drops off to 268. But the last quarter of the 20th century, 645 articles are found.

Why? We could chalk it up to several things, including these:

Roads not taken. Historians love to tell stories about success and heroism. Writing about "failures" -- even failures that may later prove useful -- is rarely done.

Women's history. Many of the people who were most vocal on issues like air pollution and the need to put public health ahead of corporate profit were ignored by traditional historians precisely because of their gender.

Industrial history. Historians who have written histories of businesses or of great enterprises are often the recipients of generous grants and cooperation from the industries about which they are writing.

Why its important now

We are only about two centuries into the industrial revolution, we often forget that renewable energy was the only energy source for most of human history.

We can appreciate the history of renewable energy as part of our "useable past." There are lessons here about roads not taken. In terms of social context, we need to understand the history of renewable energy as part of our tradition of reform.

Most importantly, renewable systems are flexible and rapidly scalable. Massive outputs of ethanol or butanol or other biofuels, in the range of billions of gallons, could be scaled up within a matter of months or a few short years. Coal and petroleum bases systems take much longer to build, as we learned in World War II.

Renewable energy sources tend to be more expensive, it's true.

Unlike fossil energy from coal or oil, or nuclear energy from uranium, renewable energy is dispersed, decentralized and more difficult to collect and concentrate.

Solar, wind and hydro power have no fuel costs, but have much higher capital costs that have to be covered initially. Fossil energy, on the other hand, has been economically more attractive even when renewables cost the same because fossil energy fuel costs are spread out over the life of the power generating plant.

Traditional economics have put renewables at a disadvantage for other reasons as well:

External environmental costs of fossil fuels and nuclear power have been imposed on populations, especially weaker segments

The costs of resource extraction from politically unstable foreign lands have been placed on taxpayers through bloated military establishments.

And so the true cost of oil, by one estimate, is between $5.60 and $15.14 a gallon.

Another cost is political. For instance, America's oil habit certainly helped turn U.S. citizens into targets of choice (Washington Post, 2001)

US government policy signals about energy have been unrealistic and totally unreliable.

But the question is, really: Can renewable technology ever be cheap enough, and provide enough power, to avert catastrophe?

Learning the lessons of the past as a guide to the future, as Thucydides said, is the point of studying history

NEXT: Renewable energy history categories

Solar Power - Developments in Renewable-Energy Technology

2008-07-01T21:15:00.000+05:30

Photovoltaic, or solar-electric, systems capture light energy from the sun's rays and convert it into electricity. Today these solar units power everything from small homes to large office buildings.

Technological improvements have made solar-electric modules more cost-effective. In the 1980s the average price of energy captured with photovoltaics was 95 U.S. cents per kilowatt-hour. Today that price has dropped to around 20 cents per kilowatt-hour, according to Collins, of the American Solar Energy Society.

The cheaper rate is still more expensive than the average national price of electricity, which in 2003 was a little over 8 cents per kilowatt-hour, according to the U.S. Department of Energy's Annual Energy Review.

Other recent advances include "thin film" photovoltaic technology, a high-tech coating that converts any surface covered with the film into a solar-electric power source.

Capturing and Storing Energy From the Sun

2008-06-30T15:52:00.000+05:30

Current interest in solar energy is not the first time people have been excited about its potential. Reportedly, the first flat-plate collector appeared in 1774. It consisted of a wooden box with three layers of glass that heated air to 140° F. By the turn of this century, development had progressed to the point that efficiencies were about as good as they are today.

Other sources of energy were more economical and convenient to use, so there was little incentive to put solar energy to work. But the finite supply of fossil fuels is now recognized, and we must prepare for the time when their cost may be much higher. An added benefit of solar energy would be reduced pollution, which will become more important as population increases.

The first consideration for any application is to reduce the energy requirement to the point where the economics of using solar collecting equipment is more favorable than investing in energy conservation measures. Most homes were constructed when fuel was plentiful and extremely cheap, so investment in solar heating and cooling should be thought about only after adequate weatherization.

The real cost of energy delivered from solar systems may range from the equivalent of $1 up to $10 per gallon of propane. At these levels, many energy conserving improvements will be economical. There is another payoff for weatherizing homes: they will be more comfortable because cold drafty conditions are reduced.

Equipment Can Prove Expensive

Energy from the sun is free, but equipment for collection, storage, and use can be expensive. A number of factors are involved in determining how much can be invested for a solar collecting system but the first cost of the equipment and the amount of energy that can be effectively used during its practical life are most important. The energy that can be used is determined by the solar energy available, ability of the collector to deliver energy, and whether that energy can be put to work or stored at the time it is collected.

An application such as water heating requires energy on a regular basis throughout most of the year, so more money can be invested in reliable, efficient hardware. Grain drying requires very large amounts of low-quality energy during a short period of time, so the system must be inexpensive or used for other applications during the rest of the year.

Investing in a solar collector depends to a great extent on tax credits granted by a State. With limitations, the Federal income tax credit of 25 percent plus the State tax credit in some States will now pay for up to 55 to 75 percent of the investment in solar equipment — which makes many solar systems economical.

Solar energy collecting systems often are classified as either active or passive. In active systems a fan or pump moves the working fluid or air through the collector. The fan or pump is turned on or off depending on whether the working fluid temperature is high enough to provide heat for storage or a process.

In passive systems the working fluid moves because of difference in density (hot air or hot water moves up and cold air or cold water moves down) or where the energy is moved by radiation or conduction heat transfer. Passive systems sometimes are defined as those where only a small amount of energy from fossil origin is used for moving the collected energy, for example one unit from fossil origin to 50 units derived from solar.

A system that combines both active and passive features is sometimes called a hybrid system and some authors classify this as a third type.

Photovoltaic collectors convert sunlight into direct current electrical energy but that method of energy collection is very expensive and used only for special purposes such as providing a small amount of energy for remote communications equipment and powering space vehicles. Therefore, this discussion is limited to applications where the function is to convert solar energy into heat energy.

Active Systems

Focusing collectors and flat-plate collectors are used for heating applications. Focusing collectors have a large area for entry of solar radiation that is then reflected onto a receiver. The entry area must be positioned so it sees the sun. This requires some type of mechanism to move the collector assembly during the day, which increases the cost of the collector.

High temperatures can be attained by focusing collectors. But most applications for heat in residences and farm service buildings can make use of energy gathered with flat-plate collectors.

Many different types of flat-plate collectors are being used or under development for putting solar energy to work in homes, farm service buildings, and agricultural processes. They range from simple systems costing very little to incorporate in the design of a new building, to more expensive equipment where cost is so high that the system would be economical only if conventional energy expenses increase.

Examples of inexpensive, simple systems are transparent roofs on farm service buildings for heating air to dry grain, or south-facing windows on residences that allow solar energy to be trapped inside. Complete systems for heating water may have an installed cost of $50 or more per square foot of collecting area.

Active systems are generally regarded as more complicated than passive systems, but a process such as grain drying can use a simple collector and maybe only one thermostat. Besides, passive systems can become complicated when controls and equipment are used to restrict natural air movement or when movable insulation is incorporated into the design. The prospective user should keep in mind that it is best to use as simple a system as possible that will provide heat for the user's needs.

Flat-plate collectors may be designed for operating only a few degrees above the outside temperature for uses such as grain drying. Those required to provide heat to a residence during winter may be designed for operating at a temperature differential of 100° F or more. Generally, cost of a flat-plate collector rises as the operating temperature differential increases.

The typical active system consists of a collector assembly, an energy storage unit, a control system, and two energy transport systems — one between the collector and storage and another between the storage and the process requiring heat.

Some vendors provide complete systems while others offer components that can be used to make up a complete system. Choosing between them depends on the type of process involved and abilities of the individual or contractor installing the system. Competent assistance should be found When planning a components system, because each component must be sized correctly to work with other parts of the system.

Backup System Needed

A backup heating system is needed because there are cloudy periods when solar energy cannot provide the necessary heat. The control system is quite important because it must be able to sense when heat can be added to storage, removed from storage, or when the backup furnace is required.

All these functions must work automatically because the typical user will not be present or may not be inclined to provide the manual controls needed to make the system work effectively.

The flat-plate collector for an active system consists of one or more of the following: 1) An absorber plate 2) A transparent cover or covers 3) Insulation behind the absorber plate 4) A box to contain the parts 5) An inlet and outlet to let the working fluid pass. The working fluid can be either liquid or air.

The bare-plate collector is used where low temperature differentials are adequate. Adding a transparent cover above the absorber allows a higher temperature to be maintained because heat loss from the absorber is reduced. A second transparent cover can be added to obtain even higher temperatures.

The absorber plate is generally made of sheet metal, or a flat surface of other material, and painted black to absorb the sun's rays. Flat black paint used for absorbers in high temperature collectors should be capable of operating at temperatures to 300° F, and possibly higher, without damage.

The absorber plate must serve to transfer absorbed solar heat to the working fluid. Fins protruding into the air may be added to the absorber, giving more surface area to transfer heat. With the liquid-type collector, the distance between liquid tubes determines how well heat can be transferred.

The weight of material in an absorber plate influences the time it takes to heat up before the working fluid can be circulated. Heavy plates require more time to heat up than light plates. During intermittent cloudiness, the plate might not heat up before a cloud cuts off solar energy. Then the heated plate would cool down while waiting for another period of sunshine.

Insulation Important

An exposed hot surface quickly loses heat, so the back side of the absorber must be insulated. Insulation between the absorber and the back of the collector box should be stable at high temperatures. Some insulations have organic materials in them that break down at high temperatures.

Vapor may deposit particulate matter on the inside of the transparent cover. This could make the collector useless until a new transparent cover is installed.

Features to reduce heat loss from the sides and ends of the collector should be incorporated into the box for the absorber plate. Collector boxes need to be sealed to exclude water, and strong enough to resist the loads imposed on them by wind and snow. Pipes or ducts entering or leaving the collector box should be insulated to reduce heat loss.

Glass has been commonly used as a transparent cover for collectors, but some plastics have desirable characteristics. Low-iron and plate glass are recommended because they absorb less solar energy than ordinary glass. The glass surface can be treated to reduce reflection, increasing transmitted energy.

Plastics are being used in many applications because construction of frames is not so critical and most plastics are somewhat less expensive than glass. Plastics resist impact stresses better than glass and generally transmit as much or more solar radiation. However, plastics generally allow more thermal energy loss than glass.

Care should be taken in selection to get plastic resistant to ultraviolet rays in sunlight and to the high temperatures encountered. The plastic should not retain a static charge which would attract dust.

Fans or pumps for moving the working fluid between the collector and storage need to be capable of long term, efficient operation. Ducts and pipes should be sealed and insulated; the amount of insulation recommended depends on the temperature difference between the working fluid and the surrounding air. Liquid leaks in pipes can be easy to spot, but air leaks in ducts present a problem because they aren't easily detected.

The control system needs to make decisions for operation of components and to be as simple as possible but still adequate to control all the aspects of operation. Where possible, users should understand the system so as to recognize when service is required or make their own adjustments and repairs.

Passive Systems

Passive solar systems are generally simple and low in cost for the quantity of heat added. Most are operated with a minimum of controls designed into the system, but may require manual adjustment.

Careful design may be required to obtain reasonably stable temperatures in the environmental space. Overheating or very cool conditions can result if the right combination of glazing and storage are not provided.

The four main types of passive solar systems are direct gain, thermal storage wall, attached sun space, and convective loop.

The direct gain system uses south-facing transparent walls, or windows, that allow solar radiation to enter directly into the environmental space that is to be heated. A part of the solar radiation is absorbed by the floor and a part reflected onto the walls and ceiling where it is absorbed.

The absorbed radiation is converted to thermal energy (heat). Some of it goes to heat up the storage material and some is lost by convection to the air which comes in contact with the floor and walls.

Movable insulation to reduce heat loss through the transparent cover at night increases overall thermal performance of this system.

The direct gain system is effective for south-facing surfaces because of the sun's low position in the sky during winter months. In summer when the sun is at a higher position in the sky, the glazed area can be shaded by overhang on the structure, awnings, or deciduous trees.

Advantages of the direct gain system are that it is one of the least expensive, simplest solar systems and can function without constructing a storage component in cases where the floor or wall can be used.

Disadvantages are degradation of fabrics and other materials in the room by ultraviolet radiation in the sunlight, temperature swings in the room which can be quite high unless thermal storage is carefully designed, the need for movable insulation to reduce heat loss through the glazing at night, and too much glare which can occur in the room during the day.

Thermal Siphon

The convective loop system has an absorbing surface placed behind the transparent cover on the south wall. This surface converts the sun's rays to heat energy that heats up the air and causes a thermal siphon effect. Cool air from the room flows up past the absorber where it is heated, and then exhausts near the ceiling. A small collector can be effective at heating a room during daytime, but there is limited storage and the room will cool off quickly at night.

Air movement caused by the thermosiphon would not be very effective at adding heat to massive walls inside the room. Thus one must be careful not to have too large a collector. At night, reverse thermal circulation can occur since the cold glass near the absorber cools it and will cause cool air to exist in the space between them which sets up a reverse circulation process. This should be prevented by closing off the loop at night.

Advantages of the convective loop system are that glare and ultraviolet degradation of fabrics are not problems, it is relatively inexpensive, it can be readily added to existing buildings, and night heat losses can be lower for other types of passive design. Disadvantages are that careful engineering and construction are required to insure proper airflow, prevent overheating, and assure adequate thermal isolation at night.

The thermal storage wall typically is a masonry wall with the south-facing side painted black to absorb solar radiation. The wall has one or two transparent covers. During the day, the south face of the wall is heated and starts the process of conducting heat through the wall. A so-called temperature wave moves through the concrete, causing the inside surface to be the wannest a few hours after sundown.

With thermal storage walls, glare and ultraviolet degradation of fabrics is not a problem, the temperature swing in adjacent living space is much lower, and designs are becoming available for allowing the proper sizing of units for homes. Disadvantages are the increased cost of constructing the wall, the space it occupies, and the amount of heat lost to the outside at night unless movable insulation is used.

Greenhouses, or similar structures called attached sunspaces, can be attached to new or existing buildings. The greenhouse is heated during the day and this warm air can be added to adjacent living space to reduce heat requirements.

A massive thermal storage wall can be used to absorb some of the solar radiation directly and transmit it to the adjacent living space and greenhouse during nighttime hours. The wall can reduce the amount of overheating that occurs in the greenhouse during daytime.

The sunspace acts as a buffer zone to reduce heat loss at night from the building to the outdoors. Advantages of the attached sunspace are that it provides smaller temperature swings in adjacent living space, reduces heat loss from adjacent living space to the outside, and is readily adaptable to existing buildings. Disadvantages are that thermal performance varies greatly from one design to another, making performance difficult to predict, and cost can be quite high if commercial buildings are used.

Storage Systems

Solar energy is received during the day and some type of storage system is required to allow that heat to be available at night. The two basic mechanisms for storing energy are to use sensible heat capacity of materials and to use the latent heat of fusion (heat given up during a change in phase from liquid to solid states).

Sensible heat capacity of a material is the amount of energy it takes to heat a unit of material. For example, it takes 1 British thermal unit (Btu) of energy to increase the temperature of 1 pound of water by 1° F. It takes about 5 pounds of rocks or concrete to store as much energy as 1 pound of water.

Even though water has the highest sensible heat storage capacity, rocks and concrete have advantages in applications such as air-type collectors and passive solar applications. Data in the table show the quantity of rocks or water required to store 500.000 Btu's of energy. This amount of energy would be equivalent to the heat produced by burning 7 to 8 gallons of propane.

Thermal energy storage properties and requirements to store 500,000 Btu's with a 30° F change in temperature.

	Rocks	Water	Phase-change material
Specific heat capacity, Btu per lb per degree F	0.2	1.0	0.5 (ave.)
Heat of fushion, Btu's per lb	-	-	100 (ave.)
Density. lbs per cu ft	90	62	100
Storage of 500,000 Btu's
Weight, lbs	88,500	16,670	4,350
Volume, cu ft	930	270¹	55²

¹2,000 gallons.
²An additional 25% for passage of air is added to volume.

Density of a material is the weight of that material that can be put in a box which is 1 foot in all three dimensions.

Multiplying the specific heat capacity by the density gives the volumetric heat capacity of a material. The volumetric heat capacity of water would be 62 while that for rocks would be 18 Btu's per cubic foot per degree Fahrenheit of temperature change. Thus water has a volumetric heat capacity over three times as great as for rocks.

Materials that change from liquid to solid at a temperature of around 90° F are being developed for the phase-change process, because large quantities of energy can be stored in a relatively small space. When water changes from liquid to solid (forms ice), 144 Btu's per pound of heat (the latent heat for fusion) are given up. Obviously, water cannot be used as a phase-change material in solar heating applications because 32° F is much too low to provide comfort.

Glauber's salt — sodium sulfate decahydrate — melts and freezes at 90° F and is one material being used for phase-change storages.

Considerable work is being done on these phase-change materials because large quantities of heat can be stored in a small space.

Phase-change material properties shown in the table are characteristic of those being used or considered for applications with solar systems. It takes four times the weight and five times the volume for water to store the same quantity of heat as this typical phase-change material. That has obvious advantages for retrofit applications because much less space is required to provide heat storage.

Rocks, Water Are Common Materials

Most energy storage systems that have been installed to date use the specific heat capacity of materials for storage. Rocks and water are both common materials and storage structures can be purchased or easily built.

An insulated steel tank is commonly used for liquid storage systems. Underground concrete tanks have been used for some larger systems, and fiber glass tanks for a number of smaller ones. Materials used to construct the tanks should be compatible with any chemical treatment the water requires.

Designs of a storage tank for water should allow for temperature stratification in the tank. This means hot water can be added to or removed from the top of the tank, and cold water can be added or removed from the bottom.

The void space between rocks in a storage allows passage of air. The rocks must be small enough so there is adequate surface area to allow heat transfer from the working fluid, air, to the rocks but large enough so the passageways allow easy movement of the working fluid. Rocks with an average diameter of 1 to 2 inches are usually recommended.

Rocks and packaged, phase-change materials are commonly used for air-type collectors. Packages for phase-change materials must be designed so there is adequate surface area for transfer of energy into or out of the unit.

All heat storage units — liquid, solid, or phase-change — must be insulated whether in the building, outside, or underground.

Reflectors

Reflecting surfaces can be positioned so they increase the amount of solar energy arriving at a collector. The correct position for a reflector depends on orientation of the collector and the season of the year during which it will be used. No general rule of thumb can be used to estimate the increase in collected energy because the changing position of the sun with the seasons affects the direction where solar energy is reflected.

The increase in collected solar energy per dollar invested in a reflector should be greater than from additional investment in collectors.

A computer simulation has been used to predict the increase in energy collected by a south-wall solar collector installed on a farrowing house in Kansas. A white-painted reflector in front of the collector and extending out as far as the collector is high (8 feet) increases collected solar energy by 15 to 16 percent. However, not all the reflected energy can be effectively used during spring and fall, so the net increase is only about 12 percent. Experimental testing has shown the computer simulation approximately correct for this Kansas location.

Information Sources

The prospective user should spend some time learning about solar energy technology. Another method is to enlist a good consultant, but the number of experienced technical personnel is limited and most are quite busy.

Sources for further study are textbooks and publications from State and Federal agencies, industrial associations, and companies selling components or complete systems. The National Solar Heating and Cooling Information Center, P.O. Box 1607, Rockville, MD 20850 provides a broad range of general information about solar energy.

Most State energy offices have personnel assigned to provide assistance on solar energy that is applicable to local conditions. They would be helpful in locating engineers and architects.

The Cooperative Extension Service provides publications and educational programs for agricultural applications. They will have plans available as they are developed.

Source: http://www.healthguidance.org/authors/488/Bob-Bergland

Storing Wind Energy Underground

2008-06-28T08:06:00.001+05:30

Wind is the fastest growing energy source in the United States. Over the last five years, wind energy output has increased tenfold. Unlike most other forms of energy used to produce electricity, wind is a variable energy source. Some wind energy may be wasted when too much energy is produced and more energy might be needed when there is not ample wind available.

A very promising technology is being developed called compressed air energy storage (CAES) that can store large quantities of wind energy. Surplus wind energy is used to pump air into layers of porous sandstone in the earth below. This underground cavern is sealed with dense shale and acts like a huge balloon. When demand for energy increases, air flows up into a natural gas-fired turbine, boosting its efficiency by 60% or more.

This technology is being implemented at the Iowa Stored Energy Park in Dallas Center, Iowa. The energy park is scheduled to be complete in 2011 after 8 years of construction. This 268-megawatt system will cost $200 million to construct, with funding from the Energy Department and municipal utilities across Iowa, North Dakota, South Dakota and Minnesota.

Batteries are also being developed that can store wind energy. American Electric Power and Siemens Wind Power are experimenting with large-scale batteries that could store a megawatt of energy. Such technologies are very pricey and could have a high environmental price tag and have a much smaller storage capacity than CAES.

The future looks bright for compressed air energy storage and wind energy. Being able to store off-peak wind energy until demand and electric rates are higher allows wind energy to be a more lucrative and consistent energy source.

goals of Night Wind project.

2008-06-28T08:03:00.000+05:30

The random production of wind energy cannot easily be accommodated on the grid by switching on and off conventional energy suppliers, like coal fired power plants, which would lead to an increase of CO2 emissions, rather than the reduction of CO2 emissions which is desired.

In order to accommodate the random production of wind energy in the grid, it would be most convenient when alternative (renewable and conventional) electricity producers could balance out the difference between production of wind energy and electricity demand. The Night Wind project aims to store wind energy produced at night in refrigerated warehouses, and to release this energy during daytime peak hours.

Nature adds some more details about the first tests of the Night Wind idea.

Later this year, van der Sluis's team will start a demonstration project by setting up a wind turbine next to the Netherlands' largest coldstore, in Bergen op Zoom, a small town in the SouthWest of the country. It shouldn't be technically difficult, he says — it's really just a question of developing software to match the temperature of the warehouses with electricity demand, turning the fridge on and off as the supply from the wind plant and the demand from consumers change during the day.

This project will officially end in June 2008 and I hope it will be a success. In the mean time, you can read this short presentation of the project, from which the diagram above has been extracted (PDF format, 3 pages, 100 KB).

Sources: Declan Butler, Nature, February 7, 2007; and various other websites

You'll find related stories by following the links below.

Storing wind power in cold stores

2008-06-28T07:59:00.002+05:30

According to Nature, a European-funded project has be launched to store gigawatts of electricity created from wind into the refrigerated warehouses normally used to store food. As the production of wind energy is variable every day, it cannot be easily accommodated on the electricity grid. So the "Night Wind" project wants to store wind energy produced at night in refrigerated warehouses and to release this energy during daytime peak hours. The first tests will be done in the Netherlands this year. And as the cold stores exist already, practically no extra cost should be needed to store as much as 50,000 megawatt-hours of energy.

Here is how Nature describes the — simple, but brilliant — idea behind this project.

The idea seems simple. Say you lowered the temperature of all large coldstores in Europe by just 1°C during the night when electricity demand is low, then let it rise 1°C by switching them off during the day when demand is at peak. The net effect would be that the warehouses would act as batteries — potentially storing 50,000 megawatt-hours of energy — and the food wouldn't melt.

Before going further, below is a diagram illustrating the idea: wind energy is optimally stored or released by following the electricity consumption patterns (Credit: Night Wind project)

In European jargon, the official denomination of the Night Wind project is "Grid Architecture for Wind Power Production with Energy Storage through load shifting in Refrigerated Warehouses." And it is led by Sietze van der Sluis, head of refrigeration and heating technology at The Netherlands Organization for Applied Scientific Research (TNO) in Delft.

Click Here to see the goals of this Night Wind Project

New Ways to Store Solar Energy for Nighttime and Cloudy Days

2008-06-26T18:55:00.001+05:30

Solar power, the holy grail of renewable energy, has always faced the problem of how to store the energy captured from the sun’s rays so that demand for electricity can be met at night or whenever the sun is not shining.
The difficulty is that electricity is hard to store. Batteries are not up to efficiently storing energy on a large scale. A different approach being tried by the solar power industry could eliminate the problem.
The idea is to capture the sun’s heat. Heat, unlike electric current, is something that industry knows how to store cost-effectively. For example, a coffee thermos and a laptop computer’s battery store about the same amount of energy, said John S. O’Donnell, executive vice president of a company in the solar thermal business, Ausra. The thermos costs about $5 and the laptop battery $150, he said, and “that’s why solar thermal is going to be the dominant form.”

Solar thermal systems are built to gather heat from the sun, boil water into steam, spin a turbine and make power, as existing solar thermal power plants do — but not immediately. The heat would be stored for hours or even days, like water behind a dam.

A plant that could store its output could pick the time to sell the production based on expected price, as wheat farmers and cattle ranchers do. Ausra, of Palo Alto, Calif., is making components for plants to which thermal storage could be added, if the cost were justified by higher prices after sunset or for production that could be realistically promised even if the weather forecast was iffy. Ausra uses Fresnel lenses, which have a short focal length but focus light intensely, to heat miles of black-painted pipe with a fluid inside.

A competitor a step behind in signing contracts, but with major corporate backing, plans a slightly different technique in which adding storage seems almost trivial. It is a “power tower,” a little bit like a water tank on stilts surrounded by hundreds of mirrors that tilt on two axes, one to follow the sun across the sky in the course of the day and the other in the course of the year. In the tower and in a tank below are tens of thousands of gallons of molten salt that can be heated to very high temperatures and not reach high pressure.

“You take the energy the sun is putting into the earth that day, store it and capture it, put it into the reservoir, and use it on demand,” said Terry Murphy, president and chief executive of SolarReserve, a company backed in part by United Technologies, the Hartford conglomerate.

Power plants are typically designed with a heat production system matched to their electric generators. Mr. Murphy sees no reason why his should. His design is for a power tower that can supply 540 megawatts of heat. At the high temperatures it could achieve, that would produce 250 megawatts of electricity, enough to run a fair-size city.

It might make more sense to produce a smaller quantity and run well into the evening or around the clock or for several days when it is cloudy, he said.

At Black & Veatch, a builder of power plants, Larry Stoddard, the manager of renewable energy consulting, said that with a molten salt design, “your turbine is totally buffered from the vagaries of the sun.” By contrast, “if I’ve got a 50 megawatt photovoltaic plant, covering 300 acres or so, and a large cloud comes over, I lose 50 megawatts in something like 100 to 120 seconds,” he said, adding, “That strikes fear into the hearts of utility dispatchers.”

Thermal storage using molten salt can work in a system like Ausra’s, with miles of piping, but if the salt is spread out through a serpentine pipe, rather than held in a heavily insulated tank, it has to be kept warm at night so it does not solidify, among other complications.

A tower design could also allow for operation at higher latitudes or places with less sun. Designers could simply put in bigger fields of mirrors, proponents say. A small start-up, eSolar, is pursuing that design, backed by Google, which has announced a program to try to make renewable electricity for less than the price of coal-fired power.

Mr. Murphy helped build a power tower at a plant in Barstow, Calif., sponsored by the Energy Department in the late ’90s. It ran well, he said, but natural gas, a competing fuel, collapsed in price, and the state had few requirements for renewable power.

“There were not renewable portfolio standards,” Mr. Murphy said. “Nobody cared about global warming, and we weren’t killing people in Iraq.”

How to Store Solar Energy

2008-06-26T17:47:00.000+05:30

If you’ve ever wondered how to store solar energy here are the basics. Solar energy is energy from the sun which is collected here on earth for heating, lighting and other human needs. Many of our basic energy needs can be addressed by using solar power. This can be done directly or indirectly but is not easy to do on a large scale. To store solar energy two components are required.

A means of collecting the solar energy and a way to generate it are needed to make sure we can access the sun’s energy. The collector collects the sun’s radiation and converts some of it to another form of energy such as electricity and heat. It is critical to find a way to store solar energy. This is because the sun does not shine for 24 hours a day and on overcast days the energy is inhibited.

The storage equipment is a way to accumulate excess energy when the sun’s rays are at maximum strength. When the sun is not shining or obscured this stored energy can be used. A backup supply also forms part of this system for times when the stored energy is insufficient. There are many ways to store solar energy. Three types of collectors are used to collect the sun’s radiation: 1) flat-plate collectors, 2) focusing collectors and 3) passive collectors.

Solar energy is very well suited for heating purposes. This heat energy can be stored in a liquid like water or a packed bed. A packed bed is a container in which small objects like stones can be placed. The stones are able to store solar energy. Heat energy can also be stored in phase-changer or heat-of-fusion units which use chemicals to alter solid to liquid at certain temperatures. Later the liquid can return to its solid form and the energy can be used.

This process is often used to store solar energy in homes to heat water. The water itself acts as the means to store solar energy. A tank is filled with hot water during the day and used when it’s required. Swimming pools can also be heated using solar energy. The water in the pool may act as a storage medium or a packed bed may be used instead. Solar energy can be used to heat homes. In this case a lot more energy is needed.

This means that larger solar panels need to be used to store solar energy. Heat-of-fusion storage units are usually used for this purpose but packed bed or hot water tanks are also sometimes used. It can be quite expensive to purchase large panels and a storage system to heat a large building. If a building is heated by solar power passive collectors are used with other storage systems.

One type of passive energy collector is the incidental heat trap. In this system heat enters through a window and falls on a stone floor. During the day the floor absorbs the heat and stays cool. At night the heat is released and heating is achieved. Another way to store solar energy is thermo-siphoning walls or roofs. In this system the heat that is absorbed and wasted in the walls and roof can be channeled for heating the home.

Solar Power: Advantages and Disadvantages

2008-06-23T18:50:00.000+05:30

There are many advantages of solar energy. Just consider the advantages of solar energy over that of oil:

· Solar energy is a renewable resource. Although we cannot utilize the power of the sun at night or on stormy, cloudy days, etc., we can count on the sun being there the next day, ready to give us more energy and light. As long as we have the sun, we can have solar energy (and on the day that we no longer have the sun, you can believe that we will no longer have ourselves, either).

· Oil, on the other hand, is not renewable. Once it is gone, it is gone. Yes, we may find another source to tap, but that source may run out, as well.

· Solar cells are totally silent. They can extract energy from the sun without making a peep. Now imagine the noise that the giant machines used to drill for and pump oil make!

· Solar energy is non-polluting. Of all advantages of solar energy over that of oil, this is, perhaps, the most important. The burning of oil releases carbon dioxide and other greenhouse gases and carcinogens into the air.

· Solar cells require very little maintenance (they have no moving parts that will need to be fixed), and they last a long time.

· Although solar panels or solar lights, etc., may be expensive to buy at the onset, you can save money in the long run. After all, you do not have to pay for energy from the sun. On the other hand, all of us are aware of the rising cost of oil.

· Solar powered lights and other solar powered products are also very easy to install. You do not even need to worry about wires.

As you can see, there are many advantages of solar energy. The advantages of solar energy range from benefiting your pocketbook to benefiting the environment. There are actually only a few features of solar energy that can be considered disadvantages.

Here are the disadvantages of solar energy:

· Solar cells/panels, etc. can be very expensive.

· Solar power cannot be created at night.

As you can see the advantages of solar energy create a much longer list that the disadvantages, and the disadvantages are things that can be improved as technology improves.

Anne Clarke writes numerous articles for websites on gardening, parenting, the enviornment, fashion, and home decor. Her background includes teaching and gardening. For more of her articles on solar power, please visit Solar Home.

Advantages of solar energy

2008-06-23T18:38:00.001+05:30

There are many advantages of solar energy. Just consider the advantages of solar energy over that of oil:

Solar energy is a renewable resource. Although we cannot utilize the power of the sun at night or on stormy, cloudy days, etc., we can count on the sun being there the next day, ready to give us more energy and light. As long as we have the sun, we can have solar energy (and on the day that we no longer have the sun, you can believe that we will no longer have ourselves, either).
Oil, on the other hand, is not renewable. Once it is gone, it is gone. Yes, we may find another source to tap, but that source may run out, as well.
Solar cells are totally silent. They can extract energy from the sun without making a peep. Now imagine the noise that the giant machines used to drill for and pump oil make!
Solar energy is non-polluting. Of all advantages of solar energy over that of oil, this is, perhaps, the most important. The burning of oil releases carbon dioxide and other greenhouse gases and carcinogens into the air.
Solar cells require very little maintenance (they have no moving parts that will need to be fixed), and they last a long time.
Although solar panels or solar lights, etc., may be expensive to buy at the onset, you can save money in the long run. After all, you do not have to pay for energy from the sun. On the other hand, all of us are aware of the rising cost of oil.
Solar powered lights and other solar powered products are also very easy to install. You do not even need to worry about wires.

Here are the disadvantages of solar energy:

Solar cells/panels, etc. can be very expensive.
Solar power cannot be created at night.

As you can see the advantages of solar energy create a much longer list that the disadvantages, and the disadvantages are things that can be improved as technology improves.

Benefits of Purchasing Renewable Energy

2008-06-17T19:47:00.000+05:30

According to the EIA, renewable energy, including hydropower and other renewables accounted for 8.8% of total U.S. energy generation in 2004. In recent years, however, there has been considerable growth in the use of renewable energy. Many state and local governments, for instance, have turned to renewable energy as a way to reduce local air pollution, reduce generation of greenhouse gases and/or stimulate the local economy. See below for more information.
Meet Greenhouse Gas Reduction Goals
In lieu of the ratification of the Kyoto Protocol by the United States, many public agencies and private businesses have voluntarily set greenhouse gas reduction goals. San Diego, for example, set a 15% GHG reduction goal in 2002 in partnership with the International Council for Local Environmental Initiatives (ICLEI). As of February 2006, 208 mayors have signed onto The US Mayors Climate Protection Agreement. These signatories have agreed to meet or exceed the Kyoto Protocol’s 7% GHG reduction goals (in comparison to 1990 levels) by 2012. For more information, go to the Pew Center on Global Change’s State and Local News page. Currently, 27 states have Climate Action Plans to reduce greenhouse gases1.

Industries and private businesses have taken initiative and partnered with the EPA Climate Leaders program to set emissions reduction goals and to monitor progress by reporting to the EPA.
Meet Air Quality Goals
Since 1990, the Federal Government, through the EPA, has set national ambient air quality standards (NAAQS) designed to regulate exposure to a list of harmful criteria pollutants. Many jurisdictions are classified as in “non attainment” and have not met these goals. Shifting to renewable energy may significantly reduce sulfur and nitrogen oxides, particularly in areas surrounding or downwind of energy production facilities. For a list of non attainment areas, visit http://www.epa.gov/air/oaqps/greenbk/

In 2004 Montgomery County included its wind purchase as an air pollution reduction strategy in the region's air quality plan, making it the first time the U.S. Environmental Protection Agency recognized wind power as a way of meeting federal air quality requirements2. For more information on this and other examples, see the EPA’s Green Power Partnership site.
Create Exportable Technology and Jobs
In the 1980’s, the US was a technological leader in solar and wind energy technology, but in the intervening years, other countries have taken the lead on many renewable technologies. A national commitment to renewable energy could allow the US to rapidly regain a position at the forefront3. Many believe that the development of domestic renewable resources could reinvigorate the local economy while helping the U.S. become more energy independent.

For example, a report published by faculty in the Energy and Resources Group and the Goldman School of Public Policy at the University of California Berkeley (Kammen et al. 2004 - http://ist-socrates.berkeley.edu/~rael/renewables.jobs.pdf ) that summarized 13 independent reports on job creation and renewable energy concluded that renewable energy generates more jobs than fossil-fuel energy for each unit of energy produced. Renewable energy operations have the potential to generate three to eleven times the number of jobs created by fossil-fuel operations, with solar and biomass exhibiting the highest potentials.

Rising oil prices makes renewable energy attractive

2008-06-17T19:44:00.000+05:30

With fuel prices soaring, renewable energy is being promoted by the state government here.
The West Bengal Green Energy Development Corporation Ltd (WBGEDC), a government agency floated for the development of green energy, is likely to come up with "renewable policy energy" framework by the end of this year

The focus areas of the policy would be to formulate certain concessions to be given to those using renewable energy, like rebate in municipal tax among other benefits, said S P Gon Chaudhuri, managing director of WBGEDCL, on the sidelines of a press conference to announce its tie-up with a Kolkata-based real estate developer to transfer green energy techniques, in Kolkata on Wednesday.

The tariff policy on the use of renewable energy was already in place in West Bengal, said Gon Chaudhuri. The policy would be divided into two parts, covering benefits to the people residing in buildings where renewable energy was being used, and independent power producers, he said. This apart, the policy will also promote the use of bio-fuels, by giving certain concessions to farmers undertaking Jatropha cultivation.

The corporation would assist the farmers in procuring Jatropha seeds and selling the end products in the market, he said. The states of Mizoram and Tripura, and union territory of Andaman and Nicobar, have also approached the WBGEDC for framing a similar policies.

"We would act as a consultant for preparing a renewable energy policy for states like like Mizoram and Tripura," he said.

The policy would be formulated with help from Indian Institute of Social Welfare and Business Management (IISWBM), he added. It will be placed before the state cabinet by the end of this year.

Benefits of Renewable Energy

2008-06-17T19:37:00.001+05:30

Renewable energy can supply a significant proportion of the United States' energy needs, creating many public benefits for the nation and for states and regions, including environmental improvement, increased fuel diversity and national security, and regional economic development benefits.

Environmental Benefits

Using fossil fuels -- coal, oil and natural gas -- to make electricity dirties the nation's air, consumes and pollutes water, hurts plants and animal life, creates toxic wastes, and causes global warming. Using nuclear fuels poses serious safety risks. Renewable energy resources can provide many immediate environmental benefits by avoiding these impacts and risks and can help conserve fossil resources for future generations. Of course, renewable energy also has environmental impacts. For example, biomass plants produce some emissions, and fuel can be harvested at unsustainable rates. Windfarms change the landscape, and some have harmed birds. Hydro projects, if their impacts are not mitigated, can greatly affect wildlife and ecosystems. However, these impacts -- which are discussed in Appendix A -- are generally much smaller and more localized than those of fossil and nuclear fuels. Care must nevertheless be taken to mitigate them.

Air Pollution

Clean air is essential to life and good health. Air pollution aggravates asthma, the number one children's health problem. Air pollution also causes disease and even premature death among vulnerable populations, including children, the elderly, and people with lung disease. A 1996 analysis by the Natural Resources Defense Council of studies by the American Cancer Society and Harvard Medical School suggests that small particles in the air may be responsible for as many as 64,000 deaths each year from heart and lung disease.[1] As the figure below shows, air pollution is responsible for more deaths than motor vehicle accidents, and ranks higher than many other serious health threats.[2] A few of the most important pollutants are discussed below.[3]

Sulfur oxides

Electricity production, primarily from burning coal, is the source of most emissions of sulfur oxides (SOx), as the figure shows. These chemicals are the main cause of acid rain, which can make lakes and rivers too acidic for plant and animal life. Acid rain also damages crops and buildings. National reductions in sulfur oxides required by the Clean Air Act Amendments of 1990 may not be sufficient to end damage from acid rain in the northeastern United States.[4] SO2 is also a primary source of fine particles in the air.

Nitrogen oxides

Burning fossil fuels either to produce electricity or to power transportation emits nitrogen oxides (NOx) into the air. In the presence of sunlight, nitrogen oxides combine with other chemicals to form ground-level ozone (smog). Both nitrogen oxides and ozone can irritate the lungs, cause bronchitis and pneumonia, and decrease resistance to respiratory infections. In addition, research shows that ozone may be harmful even at levels allowed by federal air standards. The U.S. Environmental Protection Agency (EPA) has published a new rule reducing nitrogen oxide emissions from 0.12 parts per million to 0.08 parts per million. States have until 2003 to submit plans for meeting the new standard and up to 12 years to achieve it.[5]

Carbon dioxide

Carbon dioxide (CO2) is the most important of the greenhouse gases, which contribute to global warming by trapping heat in the earth's atmosphere. Electricity generation is, as the figure shows, the largest industrial source of carbon dioxide emissions and a close second to the transportation sector.

Samples from air bubbles trapped deep in ice from Antarctica show that carbon dioxide and global temperature have been closely linked for 160,000 years. Over the last 150 years, burning fossil fuels has resulted in the highest levels of carbon dioxide ever recorded. In 1995, the Intergovernmental Panel on Climate Change -- an authoritative international scientific body -- concluded that "the balance of evidence suggests that there is a discernible human influence on global climate."[6] All 10 of the warmest years on record have occurred in the last 15 years. The 1990s have already been warmer than the 1980s -- the warmest previous decade on record, according to the Goddard Institute of Space Studies.[7]

Without action, carbon dioxide levels would double in the next 50 to 100 years, increasing global temperatures by 1.8 to 6.3 degrees Fahrenheit. The heat trapped in the atmosphere would cause expansion of the ocean's volume as surface water warms and melt some glaciers. A two-foot rise in sea level could flood 5,000 square miles of dry land in the United States, and another 5,000 square miles of coastal wetlands, as the figure shows. From 17 to 43 percent of coastal wetland-prime fish and bird habitat-could be lost. Building dikes and barriers could reduce flooding of dry land, but would increase wetland loss. Impacts on island nations and low-lying countries, like Egypt and Bangladesh, would be much worse.

Altered weather patterns from changes in climate may result in more extreme weather events. Some areas will suffer more drought and others more flooding, putting crop production under great stress in some regions. The character of our forests could change dramatically. Other expected impacts include an increase in heat-related deaths, increased loss of animal and plant species, and the spread of pests and diseases into new regions with less resistance to them.[8]

In 1997, at a conference in Kyoto, Japan, the developed nations of the world agreed to reduce carbon dioxide emissions. The United States agreed to 7 percent reductions from 1990 levels by the period 2008-2012. Senate ratification of this agreement remains uncertain, however.

SunPower increasing solar cell capacity by 150 percent in 2008

2008-06-17T19:31:00.000+05:30

In announcing financial results for the first quarter of 2008, SunPower Corporation stated that it would be increasing solar cell capacity by 150 percent in 2008, compared to capacity levels in 2007. The company also said that nearly half of its cell production was its ‘Gen2’ solar cell technology that has a minimum conversion efficiency of 22 percent.

“Our proprietary technology delivers the highest output per unit area of any commercially available solar system and we intend to leverage this technology by aggressively expanding our solar cell production by more than 150 percent in 2008 compared to 2007,” commented Tom Werner, SunPower's CEO, in a financial statement. “This scale, combined with lower silicon costs, higher efficiencies, thinner wafers and on-going quality and cost improvements in our factories, will drive unit cost reduction. During the first quarter of 2008, we continued to meet or exceed our manufacturing targets across both of our fabs and our panel manufacturing facility.”

The company also noted that it has secured 100 percent of its required polysilicon supply through 2010 to meet its revised capacity expansion plans. Last year, SunPower projected that production would top 250MW in 2008. However, revised figures revealed by the company show that figure to be 255MW for 2008.

The same is true for 2009. SunPower previously stated that it would produce 430MW in 2009; that figure has been raised to 450MW-plus. For 2010, the company is still expecting production of 650MW-plus, but has not adjusted the baseline figure upwards.

SunPower also reiterated that its capacity ramp at Fab 2 remained on schedule and was expected to be completed by the end of 2009. Its fourth solar panel manufacturing line had also completed its production ramp allowing the company to produce more than half of its PV panels in-house.

Sun Power - the real power

2008-06-17T19:25:00.000+05:30

SunPower, which makes solar cells and panels, says it has boosted the efficiency and size of its solar panels, yielding substantially more electricity than current panels.

The San Jose, Calif.-based company on Monday announced its second-generation, higher-power product at the Solar Power 2006 conference, and the panels are expected to be in mass production next year.

SunPower says it has managed to increase efficiency of the silicon cells from 20 percent to 22 percent. Further, the 5-foot by 3-and-a-half-foot panels will pack 96 individual cells within them, compared to the 72 contained in the company?s current product.

Overall, these changes result in a 43 percent increase in power, said Julie Blunden, vice president of external affairs at SunPower. Each panel can generate 315 watts of electricity and will have roughly the same cost per watt as the existing line, she said.

The theoretical limit of monocrystalline silicon cell efficiency is about 25 percent, Blunden said.

Other companies are developing solar photovoltaic manufacturing techniques around other materials, notably CIGS (copper indium gallium selenide).

But SunPower, which is owned by Cypress Semiconductor, intends to continue investing in higher solar efficiency and ways to lower the cost of installation, Blunden said.

Sunlight Solar Energy

2008-06-14T16:44:00.000+05:30

Sunlight Solar Energy, Inc. is one of the leading photovoltaic design and installation corporations in the US and is an approved contractor under energy fund photovoltaic programs in 5 states.

SSE quotes you a complete "turnkey" solar photovoltaic installation, including all necessary paperwork, permits and contracts. Sunlight Solar Energy, Inc. is a premier dealer of SunPow er.

SunPower panels and inverters are high performance and intelligent design.

Solar Energy – Turning Sunlight into Electricity

2008-06-14T16:40:00.000+05:30

Solar energy could be used to generate electricity on a large scale if solutions were found for certain problems. At present it is too difficult to produce large amounts of solar energy and store it for times when the sun is not available such as overnight, on overcast days or at high latitudes. However let’s take a look at the way in which sunlight can be turned in a source of electrical power.

Solar energy keeps us all alive. The heat and light from the sun is what keeps the earth at the correct temperature. It is the sun’s energy that keeps almost all living organisms alive. It is the sun that determines natural systems and cycles. About 95% of the energy from the sun is given off as light that we can see. However the light that we can see is only a small amount of the sun’s total energy.

The "photovoltaic effect" is a process through which a PV cell changes sunlight into electricity. The light from the sun is made up of photons. These are particles of solar energy. Depending on their wavelengths, each photon contains different amounts of energy. When photons strike a PV cell they are reflected, absorbed, or pass right through.

So how does solar energy produce electricity? When a photon is absorbed it can generate electricity. Then the energy of the photon is transferred to an electron in the PV cell (a semiconductor). The electron escapes and becomes part of an electrical circuit. When it escapes it makes a tiny hole. The PV cell has a built-in electric field. This enables the cell to provide the voltage needed to drive the electrical current into a light bulb.

Link

Generating Power from Solar Energy

2008-06-14T16:37:00.001+05:30

How Sunlight is Converted to Electricity Using Photovoltaic Process

Solar power is electricity that is generated from sunlight, and is a common choice of renewable energy for households and for large companies. There are two basic forms of solar power in current use: photovoltaics and solar thermal power.

Photovoltaic Solar Power

Photovoltaic systems, such as conventional solar panels, directly convert sunlight into energy using the principles of the photovoltaic effect. The photovoltaic effect takes advantage of the properties of semiconductor materials, with silicon being the primary material used in photovoltaic solar cells. When photons strike the solar cell, electrons in the semiconductor material are shaken loose, allowing them to flow as electricity. This electricity is direct current (DC), and can be directly used to charge batteries, or can be connected to an inverter to power alternating current (AC) components, or to be connected to the local electrical grid.

Traditional photovoltaic systems are based on silicon. Silicon ingots are sliced into wafers that are fabricated into cells. Cells are combined into modules, which are packaged into end-user systems. Silicon-based solar cells have efficiencies of approximately 14-19%. However, newer systems that use gallium arsenide, another semiconductor material, can be made into thinner and more flexible modules. These "thin film" modules can presently produce efficiencies up to 30%, but currently cost more to fabricate than traditional silicon-based modules.

ENERGY FROM WIND

2008-06-08T23:29:00.001+05:30

Wind is simple air in motion. It is caused by the uneven heating of the earth’s surface by the sun. Since the earth’s surface is made of very different types of land and water, it absorbs the sun’s heat at different rates.

During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating winds. At night, the winds are reversed because the air cools more rapidly over land than over water.

In the same way, the large atmospheric winds that circle the earth are created because the land near the earth's equator is heated more by the sun than the land near the North and South Poles.

Today, wind energy is mainly used to generate electricity. Wind is called a renewable energy source because the wind will blow as long as the sun shines.

see more from here

Renewable Energy Resources versus Fossil Fuels

2008-06-07T17:53:00.000+05:30

In modern western world the demand for energy has increased dramatically in the past century and it will grow even further and harder in the near future than ever before. The need for energy rises with upcoming markets that also need more energy. Energy is needed for cars, buses, and other means of transportation, but also to run our appliances and provides us light. Energy is also important for our safety. At night or in the dark a lot can be stolen without proper lightning. Energy is therefore needed for our development and safety.

The way we use energy today comes from knowledge that has it's foundations in the past century and before. Great men like Newton and Philips have set the path for us today to make proper use of energy. The sources which we use for our energy demand are known as non-renewable energy resources

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All About Global Warming

2008-06-04T01:34:00.001+05:30

Global warming is the term used to describe a gradual increase in the average temperature of the Earth's atmosphere and its oceans, a change that is believed to be permanently changing the Earth’s climate forever.

While many view the effects of global warming to be more substantial and more rapidly occurring than others do, the scientific consensus on climatic changes related to global warming is that the average temperature of the Earth has risen between 0.4 and 0.8 °C over the past 100 years. The increased volumes of carbon dioxide and other greenhouse gases released by the burning of fossil fuels, land clearing, agriculture, and other human activities, are believed to be the primary sources of the global warming that has occurred over the past 50 years.

Scientists from the Intergovernmental Panel on Climate carrying out global warming research have recently predicted that average global temperatures could increase between 1.4 and 5.8 °C by the year 2100. Changes resulting from global warming may include rising sea levels due to the melting of the polar ice caps, as well as an increase in occurrence and severity of storms and other severe weather events.

Biofuels emissions may be 'worse than petrol'

2008-06-02T20:47:00.002+05:30

Biofuels, once seen as a useful way of combating climate change, could actually increase greenhouse gas emissions, say two major new studies.

And it may take tens or hundreds of years to pay back the "carbon debt" accrued by growing biofuels in the first place, say researchers. The calculations join a growing list of studies questioning whether switching to biofuels really will help combat climate change.

Biofuel production has accelerated over the last 5 years, spurred in part by a US drive to produce corn-derived ethanol as an alternative to petrol.

Benefits of Renewable Energy

2008-06-02T20:46:00.000+05:30

Renewable energy provides many important benefits including:

Savings and Efficiency

Reliable Energy

Environmental benefits

Energy for the future

Jobs & the economy

Energy security

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Renewable Geothermal Energy / Geothermal Power

2008-06-02T20:44:00.000+05:30

Geothermal energy is a form of energy using the inherent warmth of the ground to create power in primarily the form of heat. Roughly six to seven feet below the surface of the ground, the temperature of the Earth is regulated. By exchanging liquids between above and below ground areas, temperature regulation can be achieved. This is mostly seen in residential situations.

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The renewable energy future

2008-06-02T20:42:00.000+05:30

Remember rain?

As Los Angeles creaks through its driest year on record and nervously awaits its next explosive wildfire, many wonder if global warming is already taking a toll. Nobody really knows; California has always had intermittent droughts, after all. But climate models predicted this situation. Changes in ocean temperatures and currents driven by things such as the melting of the Greenland ice shelf -- which is happening a lot faster than scientists expected -- will probably produce an even more desert-like climate in L.A.

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Future Power

2008-06-02T20:36:00.002+05:30

Where on Earth can our energy-hungry society turn to replace oil, coal, and natural gas?

Freedom!

I stand in a cluttered room surrounded by the debris of electrical enthusiasm: wire peelings, snippets of copper, yellow connectors, insulated pliers. For me these are the tools of freedom. I have just installed a dozen solar panels on my roof, and they work. A meter shows that 1,285 watts of power are blasting straight from the sun into my system, charging my batteries, cooling my refrigerator, humming through my computer, liberating my life.
As National Geographic reported in June 2004, oil, no longer cheap, may soon decline. Instability where most oil is found, from the Persian Gulf to Nigeria to Venezuela, makes this lifeline fragile. Natural gas can be hard to transport and is prone to shortages. We won't run out of coal anytime soon, or the largely untapped deposits of tar sands and oil shale. But it's clear that the carbon dioxide spewed by coal and other fossil fuels is warming the planet, as this magazine reported last September.

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Clean Wind Energy for Year

2008-06-01T14:18:00.000+05:30

Citizens for Pennsylvania's Future (PennFuture), an environmental nonprofit, has launched a year-long contest for Pennsylvania residents in which it will give away six compact fluorescent bulbs each month to a monthly winner and a grand prize of one year's supply of clean wind energy. (Enter here.)

Perhaps more importantly, every entrant in the contest will receive a free copy of a PennFuture brochure, "Ten Quick Actions to Help Stop Global Warming."

Great idea, happy to see...

New York Sees Renewables Progress

2008-06-01T14:17:00.000+05:30

The summary of a report on New York's Renewable Electricity Standard (RES) makes for some interesting reading. Some highlights:

Two solicitations for renewable energy have resulted in contracts for approximately 3 billion kilowatt hours (MWh) of renewable energy from 26 projects, totaling more than 800 megawatts (MW), or enough clean energy to supply approximately 400,000 average-size homes.

The New York State Energy Research and Development Authority (NYSERDA) estimates that more than $1.9 billion will be invested to build the New York-based renewable generation facilities awarded contracts under the RES. NYSERDA estimates that these investments have the potential to yield more than $720 million of in-state economic benefits over a 20-year period.

In addition to the significant economic benefits, the facilities awarded contracts under the RES could result in potential reductions of 2,000 tons of nitrogen oxides, 4,400 tons of sulfur oxides, and 1.3 million tons of carbon dioxide per year.

NYSERDA is planning a third solicitation this fall, and says, "Considering the large number of wind projects under development, a significant number of potential bidders are expected, and consequently, reasonably priced bids are anticipated."

What is happening in New York is a good example of what can happen with strong leadership at the state level. Former Gov. George Pataki (R) and current Gov. Elliott Spitzer (D) deserve enormous credit for pushing this effort forward.

Regards
kkarthikeyan

Storing Solar Power Efficiently

2008-06-01T14:06:00.001+05:30

Thermal-power plants that store heat for cloudy days could solve some of the problems with solar power.

Solar proponents love to boast that just a few hundred square kilometers' worth of photovoltaic solar panels installed in Southwestern deserts could power the United States. Their schemes come with a caveat, of course: without backup power plants or expensive investments in giant batteries, flywheels, or other energy-storage systems, this solar-power supply would fluctuate wildly with each passing cloud (not to mention with the sun's daily rise and fall and seasonal ebbs and flows). Solar-power startup Ausra, based in Palo Alto, thinks it has the solution: solar-thermal-power plants that turn sunlight into steam and efficiently store heat for cloudy days.

"Fossil-fuel proponents often say that solar can't do the job, that solar can't run at night, solar can't run the economy," says David Mills, Ausra's founder and chairman. "That's true if you don't have storage." He says that solar-thermal plants are the solution because storing heat is much easier than storing electricity. Mills estimates that, thanks to that advantage, solar-thermal plants capable of storing 16 hours' worth of heat could provide more than 90 percent of current U.S. power demand at prices competitive with coal and natural gas. "There's almost no limit to how much you can put into the grid," he says.

Major utilities are buying the idea. In July, the Pacific Gas and Electric Company (PG&E) signed a 25-year deal with Ausra competitor Solel Solar Systems of Beit Shemesh, Israel, to buy power from a 553-megawatt solar-thermal plant that Solel is developing in California's Mojave Desert. The plant will supply 400,000 homes in northern and central California when it is completed in 2011. Florida Power & Light, meanwhile, hired Solel to upgrade the 1980s-era solar-thermal plants it operates in the Mojave.

Ausra, meanwhile, is negotiating with PG&E to supply power from a 175-megawatt plant that it plans to build in California, for which it secured $40 million in venture financing this month.

What distinguishes Ausra's design is its relative simplicity. In conventional solar-thermal plants such as Solel's, a long trough of parabolic mirrors focuses sunlight on a tube filled with a heat-transfer fluid, often some sort of oil or brine. The fluid, in turn, produces steam to drive a turbine and produce electricity. Ausra's solar collectors employ mass-produced and thus cheaper flat mirrors, and they focus light onto tubes filled with water, thus directly producing steam. Ausra's collectors produce less power, but that power costs less to produce.

One megawatt's worth of Ausra's solar collectors has been producing steam in New South Wales, Australia, since 2004; the steam is fed into the turbines of a primarily coal-fired power plant. The final piece of the system--a proprietary heat-energy-storage system--should be ready by 2009.

SOLAR ENERGY AS CHEAP AS COAL!

2008-06-01T14:02:00.000+05:30

Energy company Sunrgi recently announced an astounding new solar system that will break our grids free from the fossil fuel lockdown. Their Xtreme Concentrated Photovoltaics promise a low-cost, high-efficiency system with an incredible projected energy pricing of 5 cents per kilowatt. This breakthrough puts solar on par with the cost of coal, natural gas, and other non-renewable energy sources.

If solar energy is ever going to live up to it’s world-changing potential, it’s going to have to mesh with our existing energy infrastructure, competing with coal and natural gas on price point. While traditional photovoltaic arrays span great expanses and struggle to keep costs down, Sunrgi’s system proposes a novel idea, making better use of fewer expensive materials.

The XCPV system is based on a principle blinding in its simplicity: use a magnifying glass to concentrate the sun’s energy into a single high efficiency solar cell. Each unit features a lens that magnifies the sun’s rays 2,000 times, focusing it onto a solar cell that converts more than 37% sunlight to energy. The result is a system that maximizes the potential output of each solar cell while minimizing cost and space required.

The units are modular and thus easily deployable on or off-grid, and they can be easily upgraded to accommodate future advancements in solar cell technology. To deal with the tremendous temperature of focused sunlight (more than 3,000 ºF!), Sunrgi has developed a proprietary cooling system that keeps the panels safe and sound. Rounding out the tech is a sun-tracking system and a PV cell composition that doesn’t depend on the world’s depleted silicon reserves.

Craig Goodman, president of the National Energy marketers Association, has stated that “Solar power at 5 cents per kWh would be a world-changing breakthrough. It would make solar generation of electricity as affordable as generation from coal, natural gas, or other non-renewable sources, without require and subsidy.”

Sunrgi has built and tested working prototypes, and has announced plans for commercial production in 12-15 months.

+ Sunrgi

Via nextenergynews.com

Converting wave energy into electricity

2008-06-01T14:01:00.000+05:30

Capturing wave energy and converting it into electricity is not an easy task, but researchers have developed technology to overcome the problems. Three of the pioneering devices are described here.

TAPCHAN

TAPCHAN is the name of a prototype generator that was installed on a remote Norwegian island in 1985 and has been functioning ever since. The name is an abbreviation of ‘tapered channel’, which describes the basic idea behind the device. TAPCHAN consists of a reservoir built into a cliff a few metres above sea level. Leading into it is a tapered channel – wide at the mouth, which is open to the sea, and becoming narrower as it penetrates the reservoir. Incoming waves increase in height as they move up the channel, eventually overflowing the lip of the channel and pouring into the reservoir. In this way, TAPCHAN converts the kinetic energy of the wave into potential energy, which is subsequently converted into electrical energy by a generator as the water is fed back to the sea through a pipe.

Oscillating water column

Another kind of wave energy converter is known as the oscillating water column (OWC). Like TAPCHAN, this is a fixed device – which means that the housing of the device does not move – located either onshore or fixed to the seabed. It consists of a wedge-shaped chamber that is open to the sea at the bottom. A wave surging into this chamber forces air upwards, which drives a turbine both on its way up (as the wave surges) and on its way down (as the wave recedes). These oscillations give the device its generic name. To take best advantage of this two-way flow, a special kind of turbine (such as the British-designed Wells turbine) is needed.

An Australian scientist claims to have produced an innovative OWC design that greatly improves its performance. Dr Tom Denniss, from Energetech Australia, uses a parabolic wall (shaped like a satellite dish) to focus the energy of an incoming wave. The rushing air is used to drive a special turbine he claims is four to five times as efficient as the Wells turbine. A 200-300 kilowatt prototype is under development and will probably be installed at Wollongong or Newcastle, in New South Wales.

The duck

The ‘duck’ is an example of a floating wave energy converter. It is not fixed to the shore or seabed, relying instead on the ‘nodding’ motion of floats to drive a generator. In fixed devices, the turbine is fixed while the water or air rushes past its blades. Floating devices generate their power by the relative motion of components as they bob up and down in the sea. The duck consists of rows of floats, each generating electricity that is fed ashore by a connecting cable.

One of the advantages of floating devices over fixed devices it that they can be deployed in deeper water, where wave energy is greater (since waves lose energy with decreasing water depth). There is no need for significant earthworks, either, as there is with onshore devices.

Related site

The Port Kembla project (Energetech Pty Ltd, Australia)

Wave power

2008-06-01T13:59:00.000+05:30

As any surfer knows, there’s plenty of energy in a wave. Waves are a form of solar energy – the uneven heating of the Earth by the sun causes air to move. This wind, in turn, transfers some of its energy to the surface layers of water bodies, particularly the ocean, thereby generating waves.

Putting this energy to use has proved a titanic task for scientists. For example, sea water is highly corrosive, so making generators that are sensitive to small undulations in the sea yet strong enough to withstand the inevitable storms has been a major undertaking. But scientists are now confident that many of these difficulties are close to being solved. They have developed an array of potential machines, although few have been tested commercially (Box 1: Converting wave energy into electricity).

The advocates of wave power foresee few environmental side-effects from a large-scale adoption of the technology. There is little potential for pollution – either chemical, visual or noise – and no greenhouse gas emissions. Floating devices are not expected to have any significant impact on the coastal environment, but they could present a hazard to shipping.

Australia has a huge coastline and significant wave energy resources – particularly along the southern coast of the mainland and the west coast of Tasmania. But the potential for wave power to provide a significant amount of our energy needs remains untested

Hot dry rocks – a form of geothermal energy

2008-06-01T13:58:00.000+05:30

‘Geothermal’ means heat stored in rock. The best evidence of geothermal activity can be seen in regions close to the boundaries of tectonic plates – such as Japan and New Zealand – where hot springs, volcanoes and geysers are plentiful. These resources are already being used in some countries for heating and electricity generation.

The words ‘Australia’ and ‘geothermal’ are not often closely associated. Australia doesn’t have any active volcanoes and relatively few hot springs or geysers. Yet, according to some Australian scientists, we have some of the best reserves of hot dry rocks in the world, offering prospects for a plentiful supply of energy.

Australia’s hot dry rock resources are found in granite rock layers buried up to several kilometres underground, beneath layers of sedimentary rock. They are hot – up to 300ºC – because of what is known as the radiogenic decay of minerals, in which trace elements in the granite slowly break down, releasing heat as they do.

Australian hot dry rock resources are unusually well suited to extraction because of a combination of three factors:

Heat is being generated in the crust at more than twice the global average.
The ‘blankets’ of sedimentary rock above the granite provide excellent insulation but are also of an optimal thickness for heat extraction.
The hot dry rocks are oriented horizontally, providing good (and relatively cheap) drilling access.

The process of extracting the heat is quite simple. Water is pumped down into the hot granite through a bore-hole that may be several kilometres deep. This helps to open up existing tiny cracks in the granite, increasing the permeability of the rock. The water is converted to steam by the heat and is channelled to the surface through another bore-hole, where it can be used to drive a turbine and thereby generate electricity.

Energy from hot dry rocks is not strictly renewable because the granite mass will eventually cool down. Nevertheless, it produces no greenhouse gases or other pollutants and has a very small ‘footprint’ on the landscape (unlike coal mining, hot dry rock energy requires no large-scale excavations). Some scientists say that Australia has enough hot dry rock resources – particularly in the Hunter Valley near Newcastle and the Eromanga Basin near the South Australia/Queensland border – to provide all our energy needs for centuries. A pilot project in the Hunter Valley is now underway.

Generating new ideas for meeting future energy needs

2008-06-01T13:57:00.000+05:30

This topic is sponsored by the Australian Government's National Innovation Awareness Strategy.

Concerns about the greenhouse effect, smog and energy security have led to increasing interest in energy sources such as hot dry rocks, wave power and hydrogen.

The world has changed dramatically over the last 200 years, thanks largely to fossil fuels – coal, oil and natural gas. These have provided us with cheap and convenient energy, which we use to heat and cool our homes and to run our cars, appliances and industries.

But there has been a cost. No city in the world is immune from the polluting effects of fossil fuels, and they contribute vast quantities of greenhouse gases to the atmosphere, something that many scientists believe causes global warming.

So, in the last few decades, scientists have been looking for ways to produce energy without adverse side-effects. Promising renewable energy sources such as wind, direct solar and biomass are dealt with in other Nova topics (see links at the end of this page). Now we'll have a look at hot dry rocks, waves and hydrogen. It may be some years before these energy sources make a big impact but they illustrate the diversity of options that are available.

Renewable Energy

2008-06-01T13:55:00.000+05:30

Solar energy technologies, paired with energy conservation, have the potential to meet a large portion of future US energy needs...

Renewable Energy for America's Future

2008-06-01T13:54:00.000+05:30

Energy for America's Future

President George W. Bush delivers remarks to the Washington International Renewable Energy Conference 2008 Wednesday, March 5, 2008, at the Washington Convention Center in Washington, D.C. White House photo by Chris Greenberg

President Bush Attends Washington International Renewable Energy Conference 2008

"...[L]et me start first by telling you that America has got to change its habits. We've got to get off oil. And the reason why is, first, oil is -- dependency on oil presents a real challenge to our economy. As economies grow -- and we want all our economies to grow; we want people to be prosperous, we want people who are living in poverty to be able to grow out of poverty. We want there to be general prosperity, but as economies grow, until we change our habits, there is going to be more dependency on oil."

--President George W. Bush, March 5, 2008

Wind Energy Profile: The Big Promise

2008-05-31T08:37:00.000+05:30

Theoretically, wind could produce enough energy to meet global demand. In 2006, however, less than one percent of global electricity consumption came from wind. Why such an imbalance?

Worldwide Importance and Future Prospects

Global installed wind capacity in 2006 was around 74 Gigawatts (GW), according to the World Wind Energy Association. This was more than one percent of global electricity consumption, but because installed capacity does not reflect actual production, its contributions to the global energy mix are less than that.

Wind energy capacity is expected to more than double between early 2007 and 2010. Growth will be driven by rapidly developing countries, such as India, Brazil, and China. Several offshore wind parks are being planned in northern Europe and North America. Improving efficiency and falling costs of turbine production and installation will make wind power more price competitive.

Global Resources and Producers

Global land and near-shore wind resources are around 72,000 GW, or five times the world's current energy use, according to a study at Stanford University. But sites convenient for wind power production are limited by factors such as land use for agriculture or living, distance to consumers, and technology. Experts from the Intergovernmental Panel on Climate Change estimate that only four to ten percent of given resources could be used in an economically viable way.

An entirely wind-powered economy is thus not yet possible. Global growth in wind power, however, is still tremendous. In 2005, markets grew by 41 percent. The value of new generating equipment installed in 2006 was about 18 billion euros.

Energy Output

The amount of wind energy generated depends mostly on the size, height, type, and location of a wind turbine. Some small turbines, such as those fixed on a sailboat, can generate as little as a few hundred watts - enough to power a few light bulbs. On the other side of the spectrum are the large, utility-scale turbines like the Vestas V90 that produces 3 MW. According to the manufacturer, these turbines produce in 2-3 hours the electricity that an average European family consumes in one year. The Enercon E126 turbines installed in Germany in late 2007 will produce 6MW each, making it the most powerful turbine on the market.

Most wind power turbines are still installed on land, but the future could lie offshore. Wind speeds over oceans are on average twice as high as over land, making offshore wind parks an interesting alternative, but technically more challenging alternative.

Specialized in Solar Drying and Solar hot air system

2008-05-30T23:01:00.001+05:30

PLANTATION ENERGY NETWORK
Since 1989,PEN has Installed 9000 sq.mtr of solar collector for tea leaves drying, spices drying, fruits and vegetables dehydration, dal, leather, ceramics, fish, cloth and salt drying.
Using Solar Air Heating technology 12000 tones of Fuel wood equivalent is saved and there is a reduction of 50 tones per year of green house gas emission to the atmosphere.
Ministry of New and Renewable Energy S (MNRE) and Ministry of Food Processing Industries (MFPI) both of Government of India, extended their support to Planters Energy Network through Research and Development projects.
Successfully conducted three International Conferences to disseminate the applications of Solar and other renewable energy technologies to Industries and agriculture.
PEN has the exclusive services of leading solar Scientist Dr.C.Palaniappan.
Developed innovative projects in collaboration with leading Institutions and Universities in Germany (Technical University of Munich, Munich & Institute of Agricultural Engineering (ATB), Potsdam, Berlin), Italy (International Center for Theoretical Physics (ICTP) Trieste & Ancona University), Netherlands and Australia.
Received 2 patents on its Solar Air Heating Technology.

Spain: New Plan for Renewable Energy

2008-05-30T22:53:00.000+05:30

Spain's new energy law, passed earlier this summer, is designed to attract 23 billion Euro [approx. USD$27 billion] in investment by improving the legislative environment for renewable energy.

The challenge is to make the renewable energy sector attractive to private investors, and to maintain and strengthen the interest that has been consolidated in some sectors, and extend it to others in which only timid steps have been taken so far.

-- Plan de Energias Renovables

The Energy Context in Spain

One of the characteristics of the Spanish energy system is its high degree of dependence on imports. 80 percent of energy consumption has to be met from imported sources. Spain imports approximately 64 percent of the coal, 99.5 percent of the oil and 99.1 percent of the gas it uses. Moreover, oil accounts for around 50 percent of primary energy consumption.

The strategies defined for the energy sector have been shaped by the international commitments of the European Union as a whole, and those of Spain in particular relating to energy supply and climate change. Promoting the use of energy from renewable sources plays a fundamental role in meeting both commitments.

Clearly, as is necessarily the case, Spain's energy policy objectives coincide with those established by the European Union: a competitive and transparent liberalised market, security of supply, improved energy efficiency and protection of the environment.

In Spain the development of renewable energy sources has been supported by various instruments over the last twenty-five years. A law promoting their use was first passed in 1980.

On August 26, 2005 the Spanish government approved the new Renewable Energy Plan (Plan de Energias Renovables, PER), which supersedes the Renewable Energy Promotion Plan, which dates back to 1999. The overall aim of the new Plan is to make it possible to achieve the target of 12 percent of primary energy being met from renewable sources by 2010 and to do so it sets more ambitious objectives in those areas that have been developing successfully and establishes new measures to support technologies that have not yet managed to take off.

The Renewable Energy Plan for 2005-2010 (PER)

Renewable energy sources contribute to reducing energy dependence and increasing security of supply. Moreover, the development of renewable energy can make an active contribution to job creation, generally in less favored and sparsely populated areas. They can therefore contribute to rural development and stemming the rural exodus.

The PER is an indicative Plan, meaning that it is not binding upon the actors in the energy system. However, it is hoped that slightly more than 97 percent of investments will come from the private sector. The aim is therefore to create a sufficiently attractive framework based on stability and profitability. The contribution of public funds to these investments is estimated to be just 2.9 percent.

The Institute for Diversification and Saving of Energy (Instituto para la Diversificacion y Ahorro de la Energia, IDAE), a public state-owned body, has been entrusted with the task of preparing the PER. The methodology applied during the preparation of the Plan was aimed to ensure the participation of national government, the governments of Spain's autonomous regions, and academic and professional institutions.

In each area an exhaustive analysis was conducted of state of the art technologies together with an evaluation of the requirements to overcome the main barriers to developing renewable energy sources in Spain. Concrete proposals for actions to overcome these barriers were then put forward. IDAE is also the body in charge of the monitoring of the PER.

Forecasts in the PER

In the most likely energy scenario the 2005-2010 Renewable Energy Plan targets will enable 12.1 percent of primary energy consumption to be met from renewable sources by 2010. Within this overall target, in 2010 electricity generation from renewable sources will account for 30.3 percent of gross consumption and liquid biofuels will account for 5.8 percent of petrol and diesel consumption for transport purposes.

The table below gives detailed information on the current situation and the targets for 2010.

TARGETS OF THE SPANISH RENEWABLE ENERGY PLAN FOR 2005-2010
	Situation in 2004 (average year (1)			Target in 2010
	Capacity (MW)	Energy (GWh)	Energy (ktoe)	Capacity (MW)	Energy (GWh)	Energy (ktoe)
Electricity Generation
Hydro-electric (>50MW) (3)	13,521	25,014	1,979	13,521	25,014	1,979
Hydro-electric (10 MW to 50 MW)	2,897	5,794	498	3,257	6,480	557
Hydro-electric (<10>	1,749	5,421	466	2,199	6,692	575
Biomass	344	2,193	680	2,039	14,015	5,138
Biomass power stations	344	2,193	680	1,317	8,980	3,586
Co-combustion	0	0	0	722	5,036	1,552
MSW	189	1,223	395	189	1,223	395
Wind power	8,155	19,571	1,683	20,155	45,511	3,914
Solar photovoltaic	37	56	5	400	609	52
Biogas	141	825	267	235	1,417	455
Solar thermoelectric	-	-	-	500	1,298	509
TOTAL ELECTRICITY GENERATION AREAS	27,033	60,097	5,973	42,494	102,259	13,574
Thermal uses
Biomass			3,487			4,070
Low temperature solar thermal			51	4,900,805		376
TOTAL THERMAL AREAS			3,538			4,446
TOTAL BIOFUELS			228			2,200
TOTAL RENEWABLE ENERGY SOURCES			9,739			20,220
CONSUMPTION OF PRIMARY ENERGY (ktoe) (Energy scenario: Trend/PER)			141,567			167,100
Energy from renewable sources/Primary energy (%)			6.9%			12.1%

(1) Provisional 2004 data. For hydroelectric, wind, solar photovoltaic and solar thermal, the output for an average year has been taken, based on the power output and surface area in operation as of 31 December 2004, according to the characteristics of the installations brought into operation to date, and not the actual 2004 data. Thermal biogas and geothermal energy are not included. In 2004 these produced 28 and 8 ktoe, respectively [toe = tons of oil equivalent].

Technology Targets

As the table shows, a large share of the target is based on the contribution of wind power, which is forecast to reach 20,155 MW of installed capacity in 2010. The starting point is an installed capacity of 8,155 MW at the end of 2004.

This figure has already placed Spain in second position worldwide, just behind Germany, and ahead of the United States. The development of wind power in Spain has been accompanied by the creation of companies that have developed their own technology and who compete successfully on international markets.

By contrast, biomass, which is the other fundamental pillar to achieving the PER's targets, has not developed as fast as expected. The current Plan envisages new mechanisms to overcome the barriers to its development and, as a new feature, it includes the setting up of a co-combustion programme (for the joint combustion of biomass and coal in existing power stations).

Regarding liquids biofuels for transport (LBT) the results achieved so far make it possible to be optimistic about achieving the objectives set for 2010. In the case of bioethanol Spain is the first producer in Europe.

In solar energy, within a short space of time Spain has achieved a position of international leadership in photovoltaics, with three companies in the European top ten. By contrast, one of the challenges in the Plan is to overcome the barriers to the development of solar-thermal energy. Another important innovation envisaged in the Plan is the development of the first 500 MW solar-thermoelectric power stations in 2010.

Alongside these energy targets it is hoped that other social and environmental goals will be achieved. In terms of employment over 1,300 companies are currently registered as being active in the sector. And in terms of the environment, the application of the Plan will avoid 27.3 million tons of CO2 emissions in 2010.

Funding of the Plan

Achieving the goals set implies a volume of investment estimated at approximately 23.6 billion Euros [approx. USD$27.7 billion]. Of this 97.1 percent is expected to come from private sources. Just 681 million Euros [approx. USD$799 million], 2.9 percent of the total, will be in the form of public investment aid.

The challenge is therefore to make the renewable energy sector attractive to private investors, or rather, to maintain and strengthen the interest that has already been consolidated in some sectors, and extend it to others in which only timid steps have been taken so far.

Of the approximately 22.9 billion Euros [approx. USD$26.9 billion] that it is hoped the private sector will attract, it is estimated that 4.7 billion Euros [approx. USD$5.5 billion] will come from direct contributions from developers and the remaining 18.2 billion Euros [approx. USD$21.4 billion], will come from bank loans provided through the usual financial mechanisms.

In addition to the direct investment subsidies already mentioned, there are two other modes of public aid that are fundamental from the economic point of view. These are the premiums paid for electricity generated from renewable sources and the tax exemptions for LBT.

The premiums for electricity generated from renewable sources are fundamental. This system has been used successfully to date and has created the favorable conditions for the spectacular growth of certain sectors, in particular wind power. The premium is a supplement to the price electricity producers can obtain on the market.

The total value of the premiums related to the new generating facilities brought into operation over the period 2005-2010 is predicted to reach 4.9 billion Euros [approx. USD$5.8 billion]. From 2010 the annual premiums are forecast to be worth 1.8 billion Euros [approx. USD$2.1 billion]. It is worth stressing that although the figures are large in absolute terms, the impact on electricity prices of the premium policy is an increase of around 0.6 percent a year.

The tax incentives for the use of LBT consist of an exemption from the tax on hydrocarbon fuels of the retail price. With this measure, the price of biofuels to the final consumer can be brought down to a level that allows them to compete with petroleum derivatives.

About the Authors:
Jose Gil and Hugo Lucas are in the International Relations Department of
The Institute for Diversification and Saving of Energy (Instituto para la Diversificacion y Ahorro de la Energia, or IDAE), a public state-owned body based in Madrid, Spain.

Spain is one of eight donor countries (excluding the European Union) to Renewable Energy and Energy Efficiency Program (REEEP). Austria, Germany, Italy, Ireland, the Netherlands, Spain, the United Kingdom, the United States and the European Union all contribute funds to the REEEP.

RenewableEnergyAccess.com is seeking both domestic and international contributing newswriters to communicate news, trends, issues and policy on Renewable Energy from their home countries. Please follow this link to indicate your interest.

Renewable energy plan unveiled for 2006-2010

2008-05-30T22:49:00.000+05:30

BEIJING -- China's annual consumption of renewable energy will reach the equivalent of 300 million tons of standard coal by 2010, which would be 10 percent of its total annual energy consumption, under the renewable energy development plan for 2006-2010.

The plan was released on Tuesday by the National Development and Reform Commission (NDRC), the country's top economic planning agency.

The plan says 2010 renewable energy consumption will nearly double the 2005 level, which was equivalent to 166 million tons of standard coal. That led to a reduction of 3 million tons of sulfur dioxide emissions and more than 400 million tons of carbon dioxide emissions.

Given the dearth of petroleum and natural gas resources and the large share of coal in China's energy production, it is difficult for the nation to sustain its development and protect the environment by relying simply on fossil fuels, the NDRC said.

China boasts abundant renewable resources that could be exploited, the plan says. It says that by 2010:

-- the nation will have hydropower projects with a combined installed capacity of 190 million kilowatts and wind power projects with installed capacity of 10 million kw.

-- the installed capacity of bio-energy projects will reach 5.5 million kw and that of solar energy projects will be 300,000 kw.

-- domestically produced hydropower equipment and solar water heaters should become competitive on global markets.

-- wind power equipment manufacturers should put generating units with installed capacities of at least 1.5 million watts into mass production.

cubic mile of oil (CMO)

2008-05-30T09:28:00.000+05:30

I just ran across an interesting article about renewable energy over at the Green Tech weblog. In it, they break down the type of investment that would be required to replace the energy provided by a cubic mile of oil (CMO).

In case you’re not aware (as I wasn’t), a CMO is a measure of energy consumption. Apparently the world consumes slightly more than one CMO worth of energy from oil per year, and the equivalent of three CMOs from all energy sources. Over 80% of this total energy usage comes from fossil fuels, including oil, coal, and natural gas (see graph, below).

So… What would it require to replace just one CMO of fossil energy per year?

Solar panels

Assuming annual electricity capture of 2.1 megawatts per solar panel, we’d have to place them on 4.2 billion rooftops. In other words, we’d have to install on them on 250,000 roofs per day for the next 50 years to have enough solar panels to offset our current annual oil usage (and this ignores things like coal; see below).

Wind power

What about wind power generators? You’d need 3 million to equal one CMO. That would require the installation of 1,200 per week for the next 50 years.

Hydroelectric power

A large hydroelectric dam can generate roughly 18 gigawatts of power per year. Thus, to offset one CMO of energy, we’d have to build 200 major hydroelectric dams. The problem? There aren’t enough rivers left in the world to dam up.

Solar thermal power

It would require 7,700 solar thermal plants to offset one CMO. That would require the construction of 150 plants per year for 50 years. Unfortunately, just one has been built in the past 15 years.

Nuclear power plants

It would take 2,500 nuclear power plants producing 900 megawatts to produce the equivalent of one CMO worth of energy. In other words, we’d have to build one a week for 50 years. It’s also worth noting that nuclear power isn’t exactly renewable.

The future of demand

Even if we decided to pursue one of the above options, it’s important to keep in mind that energy demand is continually increasing. According to Ripudaman Malhotra, a fossil fuels researcher at SRI International, world energy demand is expected to double to six CMOs within the next 30 years.

The good news here is that we still have time. Current estimates show oil reserves of roughly 46 CMOs, natural gas reserves totalling 42 CMOs, and coal reserves of 121 CMOs. These numbers increase further when you add in difficult to extract sources such as tar sands.

The bad news is that, beyond being non-renewable, these sources of energy also have a number of adverse environmental impacts, and burning more of them at a faster rate is just going to create more problems.

The way forward

Clearly, if we’re ever going to come anywhere near freeing ourselves from fossil fuels — an eventual necessity, as we’ll ultimately run out — it will require a tremendous investment, a variety of different technologies (likely including some that haven’t been invented yet), and an awful lot of conservation.

Unfortunately, we’re dealing with a problem on such a massive scale that minor changes won’t be enough. Consider, for example, that replacing 1 billion incandescent bulbs with compact fluorescent bulbs only saves 0.01 CMOs per year. Yes, it’s important to cut back wherever we can. In this case, however, baby steps won’t be enough.

It’s also important to keep in mind that all of the technologies listed above result in electricity production. Given that a large fraction of our energy consumption is currently non-electric, we’ll need a lot of other infrastructure changes to go along with this.

Future of Renewable Energy

2008-05-30T09:23:00.001+05:30

Nanotechnology and the Future of Renewable Energy

Nanotechnology operates at such a fundamental level that there is very little of a technological nature that it will not impact. Thus its effects on energy generation, transmission, storage and consumption are numerous and diverse. Some will be incremental and some quite possibly revolutionary.

So, greenhouse nightmare or an emission-free future? Nanotechnology can enable them both. Barring a global wave of forward planning unseen in mankind's history, economics will probably make the decision for us.

Rather than trying to sketch the whole landscape, a few examples will hopefully illustrate the variety.

At the mundane end of the scale you have anti-fouling paints for wave or tidal power, or materials with a higher tolerance for radiation in nuclear reactors. I did say mundane.

In wind power, the potentially enormous improvements in strength-to-weight ratio of composite materials used in blades could pay back surprisingly well because the relationship of blade length to efficiency is not linear but follows a power law -- though there is much argument about how this pans out in the real world.

At the other extreme of nanotech impact, you have solar energy. We are children in this area, and the playground is built on the nanoscale. Almost any development is going to involve nanotech -- an intriguing recent exception being the use of lenses to focus light on old-fashioned silicon photovoltaics, thus demanding less of this expensive material.

But what makes for a revolution in energy generation? Two things: availability and economics. The fact that solar energy is so bountiful -- enough hits the Earth in a minute to meet our global requirements for at least a week -- makes it potentially revolutionary; it's just the cost of capturing that energy that has been standing in the way. Reduce that enough, or increase the cost of the alternatives, and you have a winning scenario.

One other energy source could, I believe, be equally revolutionary. Not fusion, which, despite the dreams of my youth, I sadly have to relegate to a distant future, not that the ongoing experiments aren't worthwhile. But geothermal energy, boring as hot rocks and steam may sound, has revolutionary potential for the same reason as solar -- an essentially unlimited supply of energy untapped only because of economics.

The nanotech connection is not as direct here as with solar -- you have tougher materials to cut drilling costs or thermoelectric tunneling for efficient low-grade heat conversion -- but it only takes the right conjunction of developments and geothermal power stations will be springing up, or down, all over the place.

I've only considered here principal power generation, but this should already give some sense of the breadth and potential scale of impact. I'd be surprised to find any reader of this unaware of the excitement surrounding developments in fuel cell and battery technology. Nanotechnology figures almost without exception in the cutting edge of both.

So how do nanotechnology-based solutions apply to environmental concerns and energy security issues?

From an energy security point of view, nanotech developments are invariably positive since, at the very least, they can help save energy -- aerogels for better insulation, IR-reflective window coatings, low-grade heat conversion in cars, etc. They also assist to varying degrees in the development of alternatives to the fossil fuels upon which so many of us are now so dangerously dependent. I've already mentioned the potential of solar and geothermal energy.

On the environmental front the answer is not so clear. We live in a world where short-term economics have an overwhelming influence on decision making.

The good news for those who worry about things like global warming, is that the increasing cost of oil -- a long-term trend that will not stop, oil being a finite resource -- and the decreasing cost of alternative sources such as solar energy, give renewables an ever more favorable economic position. When you look at the diverse spread of nanotech-related impacts they are almost always supporting technologies with an improved environmental profile.

Unfortunately, there is a rather big exception to this. Nanotechnology has helped improve the effectiveness of catalysts. Fuel cells and catalytic converters are among the welcome beneficiaries.

But catalysis is also at the heart of gas-to-liquid and coal liquefaction technologies that promise oil independence for those with access to previously uneconomical gas reserves or to coal reserves. Energy security is a big carrot and it so happens that two highly populated countries that rank among the fastest-growing economies in the world, and thus the fastest-growing energy consumers, are coal-rich: China and India. North America too is coal-rich.

If such countries can start to economically run their cars, trucks and buses on diesel made from coal -- which ironically is low-emission compared with normal diesel at the vehicle end but overall produces more CO2 than oil-based diesel -- then we could be looking at a greenhouse gas nightmare scenario since there is enough coal in the world to supply our energy needs for hundreds of years.

So, greenhouse nightmare or an emission-free future? Nanotechnology can enable them both. Barring a global wave of forward planning unseen in mankind's history, economics will probably make the decision for us.

Making the Transition from Old to New Energy

I think that the likeliest difference between "old" and "new" energy, and the generator of greatest debate, will be systemic rather than one particular technology or another. The question of when and how the transition to new energy occurs is also intriguing -- as the coal liquefaction scenario above shows, we could in theory be stuck with the old, or pretty similar, for some time to come.

Only coal and nuclear fission are potential candidates for maintaining the uniform and monolithic energy network we have now in the developed world. There are good reasons to avoid both, if we can -- some would argue that we cannot.

All the alternatives involve a mix of technologies and energy sources, with energy not always being produced where you want and when you want, thus producing a far more complex system than we have now. The phrase 'intelligent grid' is often held up as an example of how this complexity will operate, with buying, selling and saving of energy being possible at many scales.

I'd rather do away with the 'grid' word altogether because it evokes the electricity grid that we in the developed world generally take for granted but which exists only as a consequence of our historical dependence on fossil fuels, and is grossly inefficient.

In a mixed-energy-source scenario, the traditional grid would be challenged by localized generation, the form of which would vary according to location: Saudi, sunshine. Greenland, geothermal.

The off-grid or localized grid scenario begs the question of how large amounts of energy will be transferred from one place to another, which will no doubt continue to be either required or an economically viable activity. The classic answer is hydrogen, but it is unfortunately a lousy way to transport energy, thanks largely to its volatility.

In theory, the development of cheap, high-load superconducting cables -- perhaps made of carbon nanotubes -- might keep the old-fashioned grid alive but it seems to me that an efficient means of converting whatever energy source happens to be available to you into a fuel that is liquid, or close to it, at room temperature -- e.g., methanol -- combined with a fuel cell technology to make good use of it, would be a hard system to beat when it comes to storage and transmission.

As I write, there are at least a few scientists around the world trying to figure out ways to outdo Mother Nature in turning sunlight into a compact, transportable energy source. All of which happens, of course, on the nanoscale.

Ten facts about renewable energy

2008-05-30T05:48:00.000+05:30

As the impact of fossil fuels on our environment becomes ever more stark, renewable energy - with its non-polluting qualities and infinite capacity - is just what we need to save our fragile planet. It's thanks to the work of engineers and scientists that we are able to harness the renewable energy available to us and make it useful. Prepare yourself for our top 10 must-know renewable energy facts...

1. There are five main forms of renewable energy: solar, wind, water, biofuel and geothermal (heat from the earth).

2. If it could be properly harnessed, enough sunlight falls on the earth in just one hour to meet world energy demands for a whole year!

3. Ever the innovator, Albert Einstein (left) won the Nobel Prize in Physics 1921 for his ground-breaking experiments with solar power and photovoltaics.

4. The geothermal energy from the core of the Earth is closer to the surface in some areas than in others. Where hot underground steam or water can be tapped and brought to the surface it can be used to generate electricity.

5. A world record was set in 1990 when a solar-powered aircraft flew across the USA in 21 stages, using no fuel at all.

6. One wind turbine can produce enough electricity to power up to 300 homes.

7. The largest wind turbine in the world, located in Hawaii, stands 20 storeys tall and has blades the length of a football pitch.

8. An average wind speed of just 14mph is needed to convert wind energy into electricity; that shouldn't be too hard to come by in breezy Britain!

9. Water is the most commonly used renewable energy resource, providing enough power to meet the needs of 28.3 million people.

10. Those clever old Romans not only gave us the modern drainage system and many of our roads, they were also among the first to use geothermal energy to heat houses.

Fun Facts about Renewable Energy

2008-05-30T05:42:00.001+05:30

Fun facts about wind power

In 200 B.C., people in China and the Middle East used windmills to pump water and grind grain.

The first modern wind turbine was built in Vermont in the early 1940s.

Wind farms currently produce enough electricity to meet the needs of more than 600,000 families in the United States.

The largest wind turbine in the world, located in Hawaii, stands 20 stories tall and has blades the length of a football field.

An average wind speed of 14 miles per hour is needed to convert wind energy into electricity.

One wind turbine can produce enough electricity to power up to 300 homes.

Learn more about wind power

Make your own wind power toys

Fun facts about biomass energy

Almost half of the renewable energy produced in the United States comes from biomass sources, li

ke wood and paper products.

In Iowa and Wisconsin, biomass energy from landfills and dairy farms is being used to make electricity.

In southern Iowa, a power plant is using a crop called switchgrass to make electricity.

Learn more about biomass energy

Fun facts about hydro power

Water power has been used for grinding grain for more than 2,000 years.

The first U.S. hydroelectric power plant opened on the Fox River near Appleton, Wisconsin, on September 30, 1882.

Worldwide, water is the most commonly used renewable energy resource, providing enough power to meet the needs of 28.3 million consumers.

Hydro power currently provides about 10 percent of the electricity in the United States.

Learn more about hydro power

Fun facts about geothermal energy

Volcanoes and geysers are examples of geothermal energy.

In 1864, a hotel in Oregon heated rooms using geothermal energy from underground hot springs.

The first geothermal power plant opened in California in 1921.

A professor at Ohio State University invented the first geothermal heating system in 1948.

Learn more about geothermal power

Fun facts about solar power

More than 10,000 homes in the United States are powered entirely by solar energy.

Enough sunlight falls on the earth's surface every hour to meet world energy demand for an entire year.

Silicon from just one ton of sand, used in photovoltaic cells, could produce as much electricity as burning 500,000 tons of coal.

In the 1830s, the British astronomer John Herschel used a solar collector box to cook food during an expedition to Africa.

Albert Einstein won the Nobel Prize in 1921 for his experiments with solar power and photovoltaics.

The first big solar power plant opened in California in 1982.

Learn more about solar power

Make your own solar oven

Renewable Energy - Facts

2008-05-30T05:37:00.000+05:30

What Is Renewable Energy?

By definition, renewable energy is "clean" - producing few or no hazardous emissions or pollutants, and having minimal impact on fragile ecosystems.

There are five main types of renewable energy: hydro, biomass, geothermal, solar and wind.

While each of these can be used to generate electricity, only hydro and biomass currently provide a significant amount of power [see chart below] - but that fact will change in the coming decades.

In addition to the obvious environmental benefits, green power could have major economic advantages as well:

It decreases our dependence on foreign oil imports and the resulting price fluctuations.

It reduces the need for costly emissions controls.

It provides new energy markets and creates new jobs.

The financial impact could be significant in the Midwest. Switchgrass and other biomass materials provide an alternative crop option, animal waste and crop residues can be sold and reused, and the construction of wind farms or other green power facilities creates jobs and local rural economies.

Sources of Renewable Energy:

SOLAR POWER

2008-05-29T18:40:00.002+05:30

During the day, there is a constant supply of radiation coming from the sun. The amount of radiation is considerable, but presently low cost commercial solid state solar cells only convert about 11% of the solar radiation into electricity. There are already laboratory solar cells that are 40% efficient, and in the future even higher efficiencies may be possible. Solid state solar cells are very attractive because they have no moving parts and are very simple. Because sunlight is free, this makes the technology very attractive especially in countries that have difficulty buying fuel. The downside of solid state solar cells is that when the sun goes down, there is no electricity being produced. Batteries can be used, but present batteries are only about 60-80% efficient in storing the electricity. Just as with wind turbines, if solar panels are linked into a large grid system, such fluctuations are not as much of a disadvantage.
A second method of using the sun's radiation is to convert it into high temperature thermal energy and then use conventional steam turbines, gas turbines or Stirling engines to generate electricity. Such methods are already 30-50% efficient in converting the sun's radiation into electricity. There are also efficient solid state thermoelectric converters being researched. If a fluid is heated, a large amount can be stored for operation of the plant during the night or cloudy days. As well, a backup fuel fired heater can be used, but this is only economical when the power plant is highly efficient.
A third desirable method is to use the sun's rays produce a fuel. This fuel could then be used at a later date. Hydrogen could be produced but it is difficult to store. An ideal fuel to produce would be ethanol or natural gas which could be used in a fuel cell at a later date to generate electricity or be used in other applications that require fuel. The solar cell would recycle the carbon dioxide from the atmosphere back into the ethanol or natural gas fuel. Such a solar cell might use genetically engineered bacteria to do the job.
Theoretically much of the thermal energy required in society could come from solar energy. Practically so far it has been considered too intermittent a source. Solar collectors for this purpose can be quite simple, but storage of the thermal energy during periods when the sun isn’t shining has so far been considered expensive compared to cheap fossil fuel. This situation could dramatically change when fuel prices go up in the future.

WIND POWER

2008-05-29T18:40:00.001+05:30

There is enough energy in the blowing winds to generate a substantial proportion of the electrical energy requirements in the world. In windy areas, the cost to produce electricity is already less than using fossil fueled combined cycle powerplants. One of the major problems with wind turbines in the past has been durability. Often serious wind storms would damage many units. Newer units appear to be built stronger. Another large problem is the extremely variable speed of the wind. Wind turbines may provide peak power in times when the electricity is not required. Storage of the electricity is expensive. If wind turbines are linked into a large grid system, such fluctuations are not as much of a disadvantage. Of course if a major proportion of our electricity would be generated this way, that would create major problems. Wind turbines in the past resulted in bird kills however it appears that with newer one’s this may not be a problem. Wind turbines are also noisy and can be unsightly. Still there are major advantages in tapping into a source of inexpensive power that can be converted into electricity in such a simple device as a wind turbine.

FUEL CELLS

2008-05-29T18:39:00.001+05:30

Fuel cells, which can convert chemical energy directly into electricity, have been proposed as a replacement for other methods of generating power from fossil fuels for 100 years. Till recently there have been numerous difficulties in commercializing them however. Will these problems be overcome in the new century? If the problems can be overcome, fuel cells will likely be the favored technology of the future for all CHP as well as large centralized powerplants. Not only do fuel cells produce reasonable efficiencies at the smaller sizes, they will likely be able to run quietly, need infrequent maintenance and emit little pollution.
A fuel cell works similar to a battery. In a battery, electricity is generated as a result of a fixed amount of substance undergoing a chemical change inside the cell. In a fuel cell, a continuous flow of chemical substance flows through the cell and is made into electricity. While a battery has a limited amount of electricity it can produce per cycle, a fuel cell can produce electricity as long as more fuel is pumped through it.
Solid oxide fuel cells will likely be the favored fuel cell for CHP [2]. Small solid oxide fuel cells will be about 50% fuel to electricity efficient, medium powerplants 60% efficient, and large one's up to 70% efficient. Their efficiency is good from about 15%-100% power. Most solid oxide fuel cells utilize both hydrogen and carbon monoxide fuel inside the cell. This means that they can readily operate on hydrocarbon fuels such as coal gas, gasoline, diesel fuel, jet fuel, alcohol, and natural gas. The efficiency of the solid oxide fuel cell used in CHP applications will be higher than the polymer electrolyte fuel cells for two major reasons. The first reason is that the hydrocarbon fuel is reformed into hydrogen and carbon monoxide fuel largely inside the solid oxide fuel cell. This results in some of the high temperature waste thermal energy being recycled back into the fuel. The second reason is that air compression is not required. Especially on smaller systems, this results in a higher amount of net electricity being produced and quieter operation.
Most polymer electrolyte fuel cells that are being developed for automobiles and CHP use hydrogen gas as a fuel. It is not likely that we will have hydrogen pipelines supplying homes and businesses in the near future. This means that hydrogen will often be extracted from hydrocarbon fuels in CHP systems. Because the polymer electrolyte fuel cell operates at a low temperature, there is no waste thermal energy recycling in the reformer. Air compression to about 3 atmospheres or higher must be used to have a reasonable power density [3]. On small systems this results in a substantial loss of efficiency. Small polymer electrolyte fuel cells will be about 35% fuel to electricity efficient, medium powerplants 40% efficient, and large one's up to 45% efficient.
Because of the high temperatures that the solid oxide fuel cell must run , they may not be practical for sizes much below 1,000 watts or when portable applications are involved. Several companies in the world are presently working on direct alcohol fuel cells. In this type of fuel cell, the alcohol is not reformed but used directly in a very simple type of fuel cell. This fuel cell is ideal for portable equipment such as power tools, laptop computers, portable phones, and emergency generators. For more information on fuel cells read the web-booklet "The Future of Fuel Cells"

MAJOR TECHNOLOGIES FOR PRODUCING POWER

2008-05-29T18:37:00.001+05:30

Electricity and mechanical power are largely used for powering our modern industrialized society. These are not stored in some natural form on earth in any great quantity. Other forms of energy must be converted. Different conversion technologies must be used. With some methods the electricity or mechanical power is produced directly in a single process. In others there are multiple steps involved.

Hydro turbines ..convert moving water from river and ocean dams into electricity
Wave generators ..use floats that move up and down with waves and produce electricity
Solar cells ..solid state materials that produce electricity directly from solar radiation impact
Thermocouples ..also called thermoelectric devices that produce electricity by heating dissimilar metals
Thermionic devices ..turn thermal energy into electricity by solid state means
Vapor turbines ..convert steam pressure into rotary motion then electricity
Piston vapor engines ..convert vapor pressure into rotary motion then electricity
Piston gas engines ..turn expanding gases to motion then electricity, Diesel, Otto, Brayton, Atkinson etc.
Gas turbines ..turn hot expanding gases to rotary motion then electricity
Stirling piston engines ..closed cycle engines turn thermal energy into motion then electricity
MHD ..turn moving charged fluids directly to electricity
Fuel cells ..turn chemical energy directly to electricity by the action of moving ions
Wind turbines ..turn moving air into rotary motion then electricity
Nuclear radiation cells ..solid state materials that produce electricity directly from nuclear radiation impact
Nuclear "ion" cells ..solid state materials that produce electricity directly from nuclear "ions"

Fig 1 Chart showing projected efficiencies of different future electricity generating powerplants

Panasonic lights up on Wind power

2008-05-29T18:36:00.001+05:30

Tokyo is well known for it’s lights. Blaring ads that rival Time Square and soak up the power grid while doing it. Godzilla stomping on buildings while the Neon lights explode. But over at Panasonic Center, environmentally conscious designers are changing that high powered perception with a design that probably had a kid’s toy as it’s inspiration.

Solar Keyring Torch

2008-05-29T18:34:00.003+05:30

The Solar Keyring Torch ensures you no longer have to fumble at the door whenever arrive home after a late night date, as it provides ample light from a trio of LEDs to keep your keyhole illuminated. Since it is solar-powered, there is no need to worry about dead batteries as well.

The best things in life are free, and sunlight is pretty well at the top of the list. The only trouble is of course, that the sun has a regular habit of shuffling off to the other side of the world leaving everything a little dark round here. Fortunately this little gizmo ensures that the sun leaves a little light behind that you can carry around with you on a key ring. It’s integral mini solar panel stores up energy from the sun and via it’s three super-bright LEDs becomes a blazing and very useful little torch when night falls. Many of these sorts of solar powered lights can have a tendency to be a tad lame, but this one is not only astonishingly bright, it also lasts for an absurdly long period of time, so long in fact that we don’t know how long it is - we got bored waiting for it to run out of power. It comes in a shock resistant rubber casing, and naturally requires no batteries, ever. Free light for life.

Torpedo Solar Spotlight

2008-05-29T18:32:00.004+05:30

What better way to lower your monthly electricity bill than rely on good ol’ solar power that never runs out (at least until our sun decides to explode)? The Torpedo Solar Spotlight makes a good candidate to spruce up your garden long after sundown at an affordable price.

Make a walkway safer, uplight a tree or highlight garden art without the hassle of running extension cords or digging trenches for wiring. These garden spotlights are solar powered! Each 2¼” reflective lens has three bright LEDs that never need replacing, and an integrated solar panel that pivots and swivels to catch the best rays. Lights come on at dusk and shine for up to eight hours.

Keep your car fresh using solar power

2008-05-29T18:32:00.003+05:30

Cars tend to attract odors, especially when several people are crammed in one for long trips. Add in a couple of smokers and the smell can become overbearing. Thankfully I don’t smoke, and most of the people that ride with me don’t either, so I just stick with the occasional pine tree air freshener. However, if you want something a little more hi-tech cleaning your air, you might try out this little gadget.