Economics and Politics of Clean Coal

Illinois Power Coal Fired Power Plant News
Jan 9, 2011	St. Louis Post-Dispatch
-=-=-=-=-=-=- Green Blog Web Post Sponsor:   Platts has valuable commodity pricing and data to share with your online community. We’ve recently updated our site to include access to more information and reports. View Energy Prices Here or  Get Your Energy Report Here -=-=-=-=-=-=-=-= The Illinois Senate's rejection of a bill to advance a next-generation coal plant just southeast of Springfield did more than potentially kill the $3.5 billion project. It highlighted the Catch-22 facing developers of this new breed of power plants: The steep price of building so-called clean coal plants deters investment -- but the cost won't come down until companies can prove the technology works, which requires actually building and operating plants. The legislation defeated at the Illinois capitol on Wednesday would have authorized the plant's owners to charge utilities above-market prices for electricity produced at the Taylorville Energy Center, which would generate enough electricity to power about 600,000 homes. But the impact of the vote could ripple even farther, potentially having a chilling effect on future clean coal proposals, including the federal government's revamped FutureGen project, a planned retrofitting of Ameren Corp.'s (NYSE:AEE) 70-year-old power plant in Meredosia, Ill. If such projects fail to move forward, that could also be a missed opportunity for Illinois coal miners, who would probably supply the fuel. "Long-term, (the effect) could be huge," said Phil Gonet, president of the Illinois Coal Association. Unlike the state's existing coal-fired plants, the Taylorville plant would not burn coal directly; instead, it would convert the black rock into a gas to more easily remove pollutants -- including much of the heat-trapping gases blamed for global warming. Developers, led by Omaha, Neb.-based Tenaska Inc., had secured $3 billion in federal tax credits and loan guarantees from the administration of President Barack Obama. But they can't begin construction without assurance that they'll be able to recover their costs over the next 30 years. Those assurances were a nonstarter for a coalition of some of the state's largest parent companies and electricity customers who argued that the bill, while protecting residential customers, would have left large employers exposed to big rate increases. Parent company information from Corporate Affiliations can give you access to nearly 700,000 company profiles.   Philip O'Connor, a former Illinois Commerce Commission chairman who led a business coalition that lobbied fiercely against Taylorville, said the group didn't oppose clean coal projects in principal. "The problem was the economics of it," he said, over budget, under fire The economics are spelled out in a lengthy study filed with Illinois regulators last year. Tenaska was required to pay for the report under a measure approved by the Legislature in 2008. Among other findings, it revealed that electricity from the Taylorville plant would cost 21.3 cents a kilowatt-hour -- about three times what big electricity users currently pay, and far more expensive than new wind power (8 cents to 12 cents per kwh) or nuclear power (10 cents to 13 cents). And that report assumed the Taylorville project would be completed on budget. The business group, which includes the Illinois Chamber of Commerce and Illinois Manufacturers' Association, worried that they would bear the brunt of any cost overruns. The spectre of runaway costs has played out in Indiana, where Duke Energy Corp. (NYSE:DUK PRA) (NYSE:DUK) disclosed last spring that the cost of its Edwardsport clean coal plant had spiked by more than $500 million to $2.88 billion. That translated to an average 16 percent increase in electricity bills by 2013. Mounting concern over the impact on electric rates convinced Illinois Sen. Kyle McCarter, R-Lebanon, to withdraw support for the Taylorville legislation. The biggest employers in his district said they faced increases of 3 percent to 7 percent. That included agricultural giant ADM, which estimated its annual electric bill would go up by $5 million. "It was made very clear, through all the research that I did, that costs to businesses in this state were going to outweigh the benefits of new jobs created," he said. Backers of the Taylorville project have rejected that argument as a red herring. They called the Senate's decision short-sighted and said it would only drive up electricity rates in the future, as aging, inefficient coal plants shut down. different plans, same problem Plans for the Taylorville and FutureGen projects, which would be about 90 miles apart, differ in key ways. They would use different technologies, and the Taylorville plant would be newly built whereas FutureGen calls for conversion of an existing coal plant. But, like Taylorville, Ameren has said FutureGen would require state legislation to guarantee that plant owners could recover their investments. An Ameren spokeswoman had no comment on the potential impact of the defeat of the Taylorville bill. "We are at the earliest stages of our project development and can't speculate on the impact this might have," spokeswoman Susan Gallagher said. The Illinois coal mining industry, meanwhile, is likely to suffer (OOTC:WLVTQ) little immediate effect from the Senate vote, said Gonet, of the state's coal association. But it could mean a lost opportunity in years to come, he said. Producers had hoped projects such as Taylorville and FutureGen would help boost Illinois coal output, which is about half of what it was 20 years ago, before restrictions on acid-rain-causing sulfur dioxide emissions led utilities to switch to cleaner-burning western coal. (OOTC:WTNCF) (TSX:WTN') (TSX:WTN) "We have 55 million tons of coal that comes in each year from Wyoming to burn in Illinois power plants," Gonet said. "We'd like the opportunity to replace that with Illinois coal." Walking away? Tenaska executives -- who have spent five years and $40 million trying to get the Taylorville project off the ground -- have threatened to walk away unless the Senate reverses itself before noon Wednesday, when the lame-duck session ends. Company officials declined to comment after Wednesday's Senate vote. But other backers of the Taylorville project say a revote by the Senate seems unlikely. John Mead, director of the Coal Research Center at Southern Illinois University Carbondale, said national energy policy was needed to help developers get projects OK'd at the state level. "I think the country as a whole expects improvement in emissions performance, and whether it's through Congress or the EPA, we're going to see that expectation turned into requirements," Mead said. "Projects like Taylorville are going to help us meet those requirements." Hannah Hess of the Post-Dispatch contributed to this report. Author: Jeffrey Tomich Jan. 9, 2011 (McClatchy-Tribune Regional News delivered by Newstex) -- Newstex ID: KRTB-0187-50770891

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‘Buy American’ Clause May Be Sticking Point in Chinese State Visit

	'Buy American' Clause May Be Sticking Point in Chinese State Visit
	Jan 10, 2011	New York Times
	KEITH BRADSHER HONG KONG — The military appropriations law signed by President Obama on Friday contains a little-noticed "Buy American" provision for the Defense Department purchases of solar panels — a provision that is likely to dismay Chinese officials as President Hu Jintao prepares to visit the United States next week. Although there are many big issues to discuss, including concerns about North Korea, trade and economic matters are certain to be high on the agenda. And while both sides are aiming to keep the discussion positive — the United States is the world's largest importer and China the largest exporter of goods — simmering resentments over trade in green-energy technologies could be a distraction. China has emerged as the world's dominant producer of solar panels in the last two years. It accounted for at least half the world's production last year, and its market share is rising rapidly. The United States accounts for $1.6 billion of the world's $29 billion market for solar panels; market analyses typically have not broken out military sales separately. The perception that Beijing unfairly subsidizes the Chinese solar industry to the detriment of American companies and other foreign competitors has drawn concern in Congress. The issue of clean-energy subsidies is also at the heart of a trade investigation under way by the Obama administration, which plans to bring a case against China before the World Trade Organization. The new Buy American provision, created mainly by House and Senate conferees during a flurry of activity at the end of the lame-duck session of Congress, prevents the Defense Department from buying Chinese-made solar panels. The American military is a rapidly growing consumer of renewable energy products, because it is extremely expensive and frequently dangerous to ship large quantities of fuel into remote areas of Iraq and Afghanistan. The solar panel provision is carefully written to help it comply with the free trade rules of the World Trade Organization, which would make it hard for China to ask a W.T.O. tribunal to overturn the provision, trade lawyers said. Chinese leaders have strongly criticized such provisions in the past, particularly one in President Obama's economic stimulus package in early 2009 that applied to government procurement of steel and construction materials. But China required in the late spring of 2009 that virtually all of its $600 billion economic stimulus be spent within China, not just for construction materials. Chinese officials in Beijing and Washington did not respond on Saturday or Sunday to requests for comment on the solar panel provision. While the United States and Europe have focused on subsidizing buyers of solar panels, China has emphasized subsidies for solar panel manufacturers. It then exports virtually all of its panels to the United States and Europe, often helped by the American and European consumer subsidies. The solar panel provision in the defense appropriations law comes as President Obama has ordered a broad investigation into whether Chinese export subsidies, local content requirements and other rules have violated W.T.O. rules. As a result of the investigation, the United States started a W.T.O. case on Dec. 22 against what it said were Chinese wind turbine manufacturing subsidies. American trade officials said then that they were still examining other Chinese clean-energy subsidy policies to decide whether to file additional W.T.O. cases. The solar panel provision was part of the initial defense appropriations bill passed by the House. The House version had a simple requirement that the Defense Department buy solar panels made in the United States. The Senate, which has been more leery of interfering with free trade, had no comparable provision, however, and many people in the solar panel industry did not expect the final law to have such a provision. But the conference of House and Senate leaders ended up retaining the House provision and modifying it, by adding legal language to require that it also comply with previous American trade legislation. Representative Maurice Hinchey, Democrat of New York, said he had fought for the provision to be included in the bill. "We've had a lot of money taken out of this country and invested in other places around the world, particularly China, and particularly in alternative energies," he said in an interview by phone. "For them to be producing alternative energy, that's great, but we need to do it ourselves, and as much as of it possible." Mr. Hinchey said he did not think the provision would jeopardize relations with the Chinese ahead of Mr. Hu's visit. "We have provided them with a lot of economic growth there," he said. "A lot of money has gone out of this country and into China, and a lot of manufacturing operations, particularly alternative energy, has also gone into China." Mr. Hinchey had praised the Obama administration in November for starting a broad investigation into Chinese subsidies for solar and wind energy exports, saying then that these subsidies had put a company in his district, Prism Solar Technologies of Highland, N.Y., at a competitive disadvantage. Two prominent trade lawyers said in e-mails over the weekend that the law's language meant that in practice, the Defense Department must buy solar panels from any country that signs the W.T.O.'s side agreement on government procurement. Earlier American trade laws require compliance with that agreement. Virtually all industrialized countries have signed the side agreement, which requires free trade in government purchases. China vowed to sign it as soon as possible when it joined the W.T.O. in November 2001, but has still has not done so. The two trade lawyers said that the United States was within its rights to discriminate against Chinese solar panels in military procurement. "The W.T.O. Government Procurement Agreement allows signatory countries, including the United States in its Defense Department contracts, to favor goods from countries that have signed that agreement over countries that have not," said Carolyn B. Gleason, a partner at McDermott Will & Emery in Washington who is one of the best-known litigators of W.T.O. cases. Alan Wolff, a former senior American trade official who is now the chairman of the trade practice at the law firm Dewey & LeBoeuf in Washington, said that it was hard to understand China's resistance to signing the agreement. "There would be a clear benefit both for it and its trading partners," he said. Solar panels are technologically complex to manufacture, and are made almost entirely in industrialized countries that have signed the W.T.O. side agreement — or in China. Inland Chinese provinces and cities have strongly lobbied Beijing not to sign the agreement because they want to retain the legal right to continue steering government contracts to local companies, said a trade policy adviser to the Chinese government who insisted on anonymity because of the political sensitivity of the issue. The Buy American provision in the 2009 economic stimulus legislation also has a little-known clause allowing purchases from other countries that have signed the Government Procurement Agreement, and not just from American suppliers. Ocean Yuan, the chief executive and president of Grape Solar, a company based in Eugene, Ore., that distributes mostly mainland Chinese solar panels but also American, Japanese and Taiwanese panels, said that imported panels typically cost 20 percent less than American-made panels. Mr. Yuan predicted that the new legislation would have a big effect on the American solar panel market, by encouraging Chinese solar panel manufacturers to establish factories in the United States. "This policy will certainly have a negative impact on the imported solar panels from China, which have lower cost over all due to lower labor and overhead costs," he said. Grape Solar sold $500,000 worth of Chinese-made solar panels to the American military shortly before Christmas, Mr. Yuan said, adding that he expected future contracts to specify American-made panels. The legislative provision was welcomed by SolarWorld, a Germany company that is one of the biggest manufacturers of solar panels in the United States and which has not followed the example of most manufacturers in moving production to China. "As a long-standing and still-expanding American manufacturer of solar technology, SolarWorld is heartened that the U.S. government and military clearly grasp the critical role of domestically produced solar technology in the country's national-security future," said Bob Beisner, managing director of the company's American subsidiary in Hillsboro, Ore., which is already installing American-made solar panels at United States military facilities at Pearl Harbor, Hawaii. The defense appropriations bill has another provision related to China. It requires that the military conduct an immediate review of its needs for rare earth metals, which are mined elements increasingly crucial in sophisticated technologies. About 95 percent of the world's supply comes from China. The bill also requires the department to establish "an assured source of supply" for rare earth metals by 2015 and to consider setting up a stockpile. Rare earths are essential for a wide range of military hardware, be it missiles or sonar. The Defense Department has been studying its contractors' reliance on Chinese supplies for more than a year. A draft report shared with Congressional aides last fall had a preliminary conclusion that rare earths were very important but suggested that the department's contractors continue to be allowed to buy them from any source. Sewell Chan contributed reporting from Denver.

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Clean Energy Dirtied by Politicians

In an Age of Compromise, Will Clean Energy Become Dirty?

By Ron Pernick, Clean Edge  

Based on the actions of a very active lame duck Congress last month, we could be moving into a new age of compromise. By crossing both sides of the aisle, President Barack Obama was able to pass comprehensive tax legislation, the repeal of Don't Ask Don't Tell, and the START nuclear arms reduction agreement in the final weeks of the outgoing Congress.

As witnessed, compromise can be a very positive and productive thing. But it also has its dark side, where compromise is so skewed it ends up achieving the opposite of what most everyone hoped for or intended. Many point to the Obama healthcare plan as a classic example of where neither side is happy with the end result. Could the same happen for clean energy?

Moving into the 112th Congress, we could see a new age where "clean energy" becomes increasingly "dirty." There are growing calls not for a national renewable portfolio standard (RPS), but a so-called clean energy standard that includes clean coal and nuclear power along with renewables. In our book The Clean Tech Revolution and in our work at Clean Edge, senior editor Clint Wilder and I have made a strong case for not including these technologies in the clean-tech taxonomy. 

But an "all of the above" approach to our energy future may very well be in the offing. The Chinese have been pursuing this approach, spending more on solar PV, wind power, and electric vehicles than just about any other country (and reaping leadership benefits along with their investments), while also supporting the advancement of clean coal and nuclear. It's not a bad approach, and has worked very well for the Chinese, but is it the right one for the U.S.?

Only One State RPS Includes Nuclear

In our recently released U.S. Clean Energy Leadership Index, Clean Edge tracks states on more than 80 technology, policy, and capital indicators, including RPS. And the states take a pretty clear view on how they feel about nuclear as part of a clean-energy future. Of the 29 states with an RPS, only one, Ohio, includes nuclear. Nuclear containment issues and waste storage problems all weigh heavily on the minds of local residents, not to mention greater overall public support for the expansion of renewables over conventional sources.

Arizona, for example, aided by the adamant voice of the state's solar industry and others, recently put a stop to legislation that would have allowed existing nuclear and hydro facilities to count towards the state's RPS – which would have effectively killed any incentive to install new renewables.

One of the other big issues facing nuclear power is that you're always just one accident away from broad social rejection of the technology. People forget about the latest pipeline explosion or the latest coal mine accident, but they don't do that with nuclear power accidents. This makes the wide-scale adoption of nuclear all the more difficult and potentially impractical.

But let's face it. Candidate Obama wasn't against nuclear or clean coal, so we shouldn't expect much different from President Obama. And his Secretary of Energy, Steven Chu, has been vocal in his support of nuclear power, stating that he doesn't see a way out of our current energy mess sans nukes (see our rebuttal to that here). So the idea of a clean-energy standard that includes both nuclear and clean coal isn't at all far-fetched. It is an increasingly likely reality.

But we can do better.

China may need to pursue nuclear and clean coal along with its leadership role in renewables, electrified transportation, and efficiency. But the U.S., with its more advanced existing infrastructure and smaller projected demand growth, doesn't have to. We could be one of the first nations in the world to wean itself off of coal and nuclear while replacing these volatile sources of energy with a combination of cleaner options. Recently, the state of Oregon decided to shutter its only coal plant by 2020, by ratcheting up renewables and efficiency, along with some base-load natural gas. This could be achieved across our entire country.

If we do end up with a broad federal clean-energy policy that includes clean coal and nuclear, then let's be sure it's structured so that states can say no to these technologies. Let California, Oregon, Massachusetts, Washington, and others pursue their own strategies to reach low-carbon goals.  There's a reason why so many states have chosen not to include nuclear and clean coal in their targets, and the feds should stay out of the way on this one.

Like many others, I believe that solar, wind, geothermal, smart grid, electric vehicles, and conservation and efficiency, along with intelligent use of conventional sources like natural gas, represent our energy future. Let's not get distracted by expensive, polluting, volatile, and resource-intensive alternatives. The U.S. can and must lead in the clean-energy revolution, and it can do so by supporting, leveraging, and growing the cleanest of clean technologies.

Ron Pernick is cofounder and managing director of clean-tech research and advisory firm Clean Edge, Inc. He'll be moderating a discussion on nuclear power between Ralph Cavanagh, NRDC and Peter Schwartz, GBN/Monitor Group, at the upcoming Clean-Tech Investor Summit in Palm Springs.

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Optimized and Efficient Window Placement Suggestions for Home Builders

Though windows are only one target among several products and practices toward a top-notch thermal envelope, there are still rules of thumb to follow to optimize their impact.

Southern Exposure: An all-day exposure, per the sun's path. In heating (i.e., cold) climates, leverage it with a better U-factor (ideally 0.20 or less) but less-efficient SHGC (perhaps 0.50 or higher) to boost heat gain in the winter and offset heating energy; use overhangs or other shading devices to cut down gain in the summer, when the sun is higher in the sky. In cooling (i.e., hot) climates, spec windows with U-factors and SHGC ratings of 0.30 or better and use shading tactics. "If I have to choose between blocking the summer sun and some solar gain in the winter, I'll elect to block it," says Texas custom builder Don Ferrier.

Western Exposure: Solar gain mostly in the late afternoon. Bob Saxler, architectural marketing manager at Andersen Windows, advises builders to focus on this elevation first, as it is the most difficult to control. If possible, orient the house and floor plan away from this exposure, such as situating utility areas, bathrooms, and, ideally, the garage on that side, and specify small and fewer operable (ideally casement) windows with efficient U-factors and SHGC ratings to mitigate solar gain and provide some measure of passive ventilation. If you have a view to the west, he says, boost the SHGC even more and look for multiple shading opportunities inside and out.

Northern Exposure: In this hemisphere, the least opportunity for solar gain. A dual-pane window with a standard low-E coating on the inner face of the outside pane (cold climate) or the outer face of the inside pane (hot climate), is sufficient. "We always recommend a low-E window for north-facing windows for its insulating value alone," says Val Brushaber, director of product management, certification, and architectural development for Hurd Windows & Doors. The number and size of windows can be dictated by views, exterior aesthetics, and floor plan as much as thermal efficiency, though fewer windows is always better in that regard. North is also notorious for prevailing winds, so think about air infiltration and passive ventilation through casement windows (instead of hung units) or fixed windows to lessen leakage.

Eastern Exposure: Rich in daylight, but far cooler than its opposite exposure. You can dial up the SHGC rating to 0.40 or more, especially in heating or mixed climates, while a U-factor of 0.30 is plenty to retard thermal transfer through the window.

Article Continues: ecohomemagazine.com/green-products

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Green Product Evaluation Tips

Here are the first 12 questions you should ask about any green building product you're evaluating—before you make your selection:

1. How will it perform its basic function as a building material or product?

2. How does it compare with products I use now?

3. Is it code approved? 

4. Is it third-party certified? 

5. Will it contribute toward project certification? 

6. Is it available? 

7. How will it affect my pricing? 

8. Will it increase my level of risk or liability? 

9. How will it improve the level of performance of my homes? 

10. How will it contribute toward sustainability? 

11. Will it require new sequencing or installation skills/trades? 

12. Is it worth the investment for the benefits?

After answering these 12 questions, apply your own experience and expertise to filter out products that would put you outside your comfort zone in terms of unknowns and risks.

Read Complete Article Here: www.ecohomemagazine.com

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Spray Foam: Open Cell VS Closed Cell

Scotty writes: In response to a prior questions:

Q:Which Spray Foam Insulation is Best, Open Cell or Closed Cell?

Open-Cell Vs. Closed-Cell

The real distinction between types of foam insulation focuses on whether they are open- or closed-cell. In general, both are made from the same materials and work in the same way, trapping air or gas in a plastic matrix. The differences start with the "blowing agents" used to create bubbles and end with both varied performance and cost.

Open-cell foam costs slightly less for the same thickness, but offers lower per-inch R-values than closed-cell products. In some instances, this is a disadvantage, but where thickness is less relevant, or where higher R-values are not needed, then open-cell can provide the better choice. It also has some green advantages over closed-cell: The blowing agent used to install open-cell insulation is water, which reacts with air to become CO2—while closed-cell products use HFCs.

Because CO2 expands quickly, the bubbles tend to burst before the plastic sets, and hence the "open cells," which produce a spongy, lightweight foam. The industry describes the foam as "half-pound" material, which simply means the foam has a mass that weighs 0.5 pounds per cubic foot. This density yields an R-value of approximately 3.6 per inch, equivalent to most traditional insulations. Because of the open cell structure, open-cell foam allows some vapor to pass through, making it a good choice in hot, humid climates, and under roof sheathing, such as in conditioned attics, where water vapor caught between insulation and sheathing could promote wood rot.

In short, open-cell foam, tested in accordance with ASTM E 283, provides an air barrier with vapor breathability. Water-blown solutions have less environmental impact than the current HFCs used for most closed-cell spray-foam insulation. And open-cell has about twice the noise reduction coefficient in normal frequency ranges as closed-cell foam. Because the blowing agent in open-cell insulation dissipates as it sets, instead of slowly over time, there is no degeneration of the R-value—a minor point given aged closed-cell R-values still trump open-cell R-values by a magnitude of nearly 100%.

Unlike open-cell foam, closed-cell foam uses chemical blowing agents that come in liquid form and become gasses as they are applied. These gasses expand, but not as quickly as CO2, allowing the polyurethane plastic to set before the bubbles burst. This yields dense foam weighing nearly 2 pounds per cubic foot, and without the capillary characteristics of open-cell, it remains impermeable. The blowing agents used perform like the inert gasses between the panes of high-performance windows, adding to the insulating qualities of the foam. Unlike open-cell foam, closed-cell foam rarely requires any trimming, with little or no jobsite waste.

Closed-cell has more obvious advantages over open-cell, and a slightly higher price tag (20% to 30% for the same thickness). It provides both a vapor and air barrier and offers an aged R-value of a whopping 6.5 per inch. Because of its density and glue-like consistency, it remains very strong, providing both compressive and tensile strength to structure comparable to added sheathing, increasing the racking strength of walls by as much as 300%, according to the NAHB Research Center. Because water does not penetrate or degrade the product, FEMA recommends closed-cell foam as a suitable insulation material for flood regions.

The principle disadvantage of closed-cell foam comes with overkill. If you do not require the extra vapor barrier, structural strength, and R-value per inch, then you may be wasting money. As for the added wall strength, while real and substantial, it's not acknowledged by building codes currently, so you can't reduce the structural bracing as a tradeoff.
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Information found at: http://www.ecohomemagazine.com

Spray Foam: Toxic Blowing Agents and Fire Proofing ecohomemagazine.com/green-products/expanding-options.aspx

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Solar Break-Thru: Two Energetic Electronic States from One Photon

Scientists Generate Two Energetic Electronic States from One Photon

Double yield via singlet fission could mean 35% efficiency boost for solar

December 2, 2010

Researchers from the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) and the University of Colorado, Boulder (UCB), have reported the first designed molecular system that produces two triplet states from an excited singlet state of a molecule, with essentially perfect efficiency.

The breakthrough could lead to a 35 percent increase in light-harvesting yield in cells for photovoltaics and solar fuels.

The experiments, using a process called singlet fission, demonstrated a 200 percent quantum yield for the creation of two triplets of the molecule 1,3-diphenylisobenzofuran (DPIBF) at low temperatures.

In singlet fission, a light-absorbing molecular chromophore shares its energy with a nearby non-excited neighboring molecule to yield a triplet excited state of each. If the two triplets behave independently, two electron-hole pairs can be generated for each photon absorbed in a solar cell. This process could subsequently increase by one third.the conversion efficiency of solar photons into electricity or solar fuels.

The researchers identified DPIBF as a promising candidate while searching for molecular chromophores that have the required ratio of singlet and triplet energy states.

Earlier, NREL and Los Alamos National Laboaratory had demonstrated an analgous two-electrons-from-one photon bonus using semiconductor quantum dots in a process NREL termed Multiple Exciton Generation. The latest advance is the first to demonstrate the electron multiplication phenomenon via  the singlet-fission process in molecules.

Until this most recent advance, singlet fission had been known as a somewhat obscure phenomenon occurring at low efficiency in a small number of molecular systems. In 2004, NREL and UCB revisited singlet fission as a potential way to maximize solar photon conversion efficiency. In 2006, NREL’s Arthur J. Nozik and Mark C. Hanna calculated the gains in thermodynamic efficiencies that were possible with solar cells based on singlet fission. These activities led to a much more extensive search for the best candidate molecules in a collaboration between NREL and the research group at the UCB led by Josef Michl.

The research has been published in the Journal of the American Chemical Society.  Authors are NREL’s Justin C. Johnson and Arthur J. Nozik, and UCB’s Josef Michl.  For a technical summary of this article, please visit http://www.nrel.gov/news/pdfs/technical_summary_20101202_press_release.pdf

NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for DOE by the Alliance for Sustainable Energy, LLC.

Visit NREL online at www.nrel.gov