Scientists report first solar cell producing more electrons in photocurrent than solar photons entering cell
The external quantum efficiency for photocurrent, usually expressed as a percentage, is the number of electrons flowing per second in the external circuit of a solar cell divided by the number of photons per second of a specific energy (or wavelength) that enter the solar cell. None of the solar cells to date exhibit external photocurrent quantum efficiencies above 100 percent at any wavelength in the solar spectrum. The external quantum efficiency reached a peak value of 114 percent. The newly reported work marks a promising step toward developing Next Generation Solar Cells for both solar electricity and solar fuels that will be competitive with, or perhaps less costly than, energy from fossil or nuclear fuels. A paper on the breakthrough appears in the Dec. 16 issue of Science Magazine. Titled "Peak External Photocurrent Quantum Efficiency Exceeding 100 percent via MEG in a Quantum Dot Solar Cell," it is co-authored by NREL scientists Octavi E. Semonin, Joseph M. Luther, Sukgeun Choi, Hsiang-Yu Chen, Jianbo Gao, Arthur J. Nozikand Matthew C. Beard. The research was supported by the Center for Advanced Solar Photophysics, an Energy Frontier Research Center funded by the DOE Office of Science, Office of Basic Energy Sciences. Semonin and Nozik are also affiliated with the University of Colorado at Boulder.
Warren Buffett's MidAmerican Energy Holdings made its second foray into solar energy in as many weeks, saying on Friday it will buy a 49 percent stake in an Arizona power plant from NRG Energy Inc (NRG.N). MidAmerican, the utility affiliate of Buffett's holding company Berkshire Hathaway Inc (BRKa.N), said it will take a stake in the 290-megawatt Agua Caliente project in Yuma County, Arizona. The plant is being built by solar power company First Solar Inc (FSLR.O) and is supported by a $967 million loan guarantee from the U.S. Department of Energy. The announcement comes a little over a week after MidAmerican said it would buy First Solar's 550 MW Topaz Solar Farm power plant in California.
Shares in solar power company First Solar fell over 20% in early trading Wednesday after the firm lowered its sales forecast for 2011. The Arizona-based company, which is a leading maker of thin-film solar panels and also a developer of solar power projects, predicted net sales in 2011 of $2.8 to $2.9 billion. That's down from earlier projections of $3.0 to $3.3 billion. The company said the lower sales were due to delays in its projects caused by weather and "other factors," but predicted a healthy 2012. "Our diverse business model and robust project pipeline will help First Solar generate a significant amount of cash in 2012 while improving operational efficiencies," Mike Ahearn, Chairman and Interim CEO of First Solar, said in a statement Wednesday.
While energy from wind turbines currently accounts for less than one percent of total power generated in Japan, the new breakthrough in design provides ample reason to ramp up production. Called the 'Windlens,' Yuji Ohya, a professor of renewable energy dynamics and applied mechanics, and his team at Kyushu University have created a series of turbines that could make the cost of wind power less than coal and nuclear energy. The two major concerning issues with traditional turbines have been their general inefficiency and intolerable noise. However, Kyushu's researchers found that attaching an inward curving ring around the perimeter of a turbine's blades increases the focus of airflow faster through the blade zones at two to three times the speed as before. An improvement in safety from covering the outer edges of the blades and a reduction of the dreaded noise pollution of older models is just a bonus.
The agreement by investor Warren Buffett's MidAmerican Energy Holdings to buy a $2-billion photovoltaic farm in San Luis Obispo County could bring a ray of financial sunshine to the battered solar-energy industry. The scale of Buffett's foray into this sector of the renewable energy scene is considerably more modest than his $34-billion purchase of BNSF Railway, but it could provide the same kind of boost to the solar power business that the 2009 acquisition did to the railroad industry, experts said. "In a lot of ways, this is classic Warren Buffett," said Bruce Bullock, executive director of the Maguire Energy Institute at Southern Methodist University. "He comes into an industry that is starving for capital investment. At the same time, this is something that also tells people it's time to take solar power seriously."
THE sight of electric cars umbilically attached to their charging stations hasn't yet become commonplace. But already the technology is about to be superseded. Nissan in Japan has given a glimpse of the very near future in the form of a wireless charging station for its Leaf electric car. Present electric vehicle charging technology requires the connection of a cable to the vehicle to recharge its battery via mains electricity. Now Nissan has developed a wireless charging pad that recharges the battery simply by parking the vehicle on top of a ground transmission unit. Much like the charging system on electric toothbrushes, the Nissan wireless charger works by electromagnetic induction. Electricity is drawn from the recharging coil in a housing mounted on a garage floor and into contacts inside the vehicle. Charging your EV is something you never have to think about. You simply drive into the garage at night, park squarely over the charging pad, and leave the car to charge itself. By morning the car is fully charged and you're on your way. The system is 90 per cent as efficient in power transmission as a cable system, meaning it will charge the car in about eight hours.
Belkin this month released perhaps the simplest way to cut that standby power with its Conserve Power Switch. The small gadget is just a switch in a handy format that cuts the flow of power to anything that plugs into it. There's not much to this device, but that's its appeal. The Power Switch, which costs $6.99, plugs into a regular outlet and you plug a device into that. When you want to use your coffee machine, flick it on and a small green light turns on to indicate the plug is live. Could this simple act actually be worth it? Depending on what power source you intend to cut off, this little gadget or one like it can pay for itself in less than a year. Lawrence Berkeley National Laboratory calculates that the average coffee maker uses 12 watts when it's off. That means if you only turned it on for the few minutes that it's actually making coffee, you'd save about $12 a year based on the national average electricity price.
The European wind energy market is just starting to recover from the economic downturn in 2009. As demand stabilises, steady growth is forecast. At the same time, the market is poised for greater consolidation that will result in the emergence of fewer but stronger participants. New analysis from Frost & Sullivan (http://www.energy.frost.com), European Wind Energy Markets, finds that the market earned revenue of $19.18 billion in 2010 and estimates this to reach $42.48 billion in 2017. The application sectors covered in this research service are offshore and onshore wind energy. "Europe's wind energy market is primarily driven by the European Union's renewable energy agenda to meet 20 per cent of its energy needs through renewable sources by 2020," notes Frost & Sullivan Research Analyst Neelam Patil. "The high growth potential of offshore wind energy, coupled with the emerging markets of Central and Eastern Europe (CEE) are attracting investments in the European market."
A lack of progress for battery technology is (arguably) the single biggest barrier for gadgets, electric vehicles and the power grid. But there continues to be innovation, like last week researchers at Northwestern University unveiled technology that can boost gadget battery life by ten and charge a battery in minutes instead of hours. And there’s hundreds of researchers, entrepreneurs, universities and large companies working on battery breakthroughs. Here’s 25 you should know about:
Ascent Solar Technologies, Inc. a developer of lightweight, flexible, thin-film photovoltaic modules, announced today that itsflexible CIGS solar panels were named one of TIME's 50 Best Inventions of 2011. Ascent's technology was one of six ‘green' inventions to be recognized in this year's list, featured in the Nov. 28 TIME issue. For each of the past 10 years, TIME has recognized the top 50 breakthroughs in science, technology and the arts. Previous honorees have included the iPad, Nissan Leaf, 3-D cameras, and the world's first synthetic cells. "We are honored to be recognized by TIME as one of this year's top 50 inventions," said Ascent Solar President and CEO, Ron Eller. "Our flexible solar panels integrate seamlessly with countless applications across a wide variety of markets. TIME's recognition further validates the transformational aspects of Ascent's technology."
Twenty-one cleantech startups from across the U.S. competed for a grand prize of $250,000 in seed investment and services at this year’s Cleantech Open Business Competition. On Wednesday night, the not-for-profit organization awarded the national grand prize to the winner in the renewable energy category, Atmosphere Recovery, which makes laser-based gas analyzer systems for efficient manufacturing and advanced energy process control. See the full list of winners here.
A recent report by Bloomberg New Energy Finance demonstrated that, in spite of plunging stock prices, investment in utility scale renewable energy was higher in Q3 than in any other quarter and up by 16% compared to this time last year. The second shock of the report was that it was the US cleantech sector taking the lead in terms of investment, overtaking the usual front runners Europe and China. This seemingly positive news is however tainted with some worries from investors and the cleantech sector. Some believe Solyndra's high profile collapse will affect government support of renewable incentives, whilst others expect the expiry of the Treasury cash grant at the end of the year to dampen the development of utility scale projects. Building upon Bloomberg New Energy Finance's findings, Green Power Conferences and the Solar Power Generation USA congress invited over 35,000 professionals from the solar and finance communities to take part in a 5 minute survey to assess industry confidence for 2012. Despite expected difficulties in the market, over 60% of respondents thought that investment in the utility scale solar sector would increase in 2012, whilst 20% thought it would stay the same as 2011 levels.
The U.S. Commerce Department said it would investigate whether Chinese companies sell solar panels in the United States at unfair discounts and receive illegal government subsidies. The trade spat, one of several sensitive economic and trade issues between the United States and China, could lead to steep duties on imports of Chinese panels and help struggling domestic manufacturers. The action is opposed by companies in the U.S. solar industry that count on importing cheap panels to boost solar power generation. It comes as the administration of President Obama faces criticism from Republicans in Congress about domestic aid to solar and other renewable energy companies. The Commerce Department said Wednesday that it had accepted a petition from SolarWorld Industries Americas Inc. Last month, the company asked the U.S. government to slap duties on Chinese solar cells and modules.
According to PROINSO sources , companies or individuals can make a selection of orders that can be modified according to what the customer agrees with the PROINSO sales department, which will send the customer an offer. Each installer can sign in with a username and password, and they will have a sales representative in their country. "The selection of purchase orders made with the online tool does not mean the customer must make the purchase. Availability can be checked and delivery dates and final prices can be negotiated before an order is actually placed," they said. Read the full news release here.
Sometime shortly after 7 a.m. PST on Monday, execs at algae oil company Solazyme, members of the media and others will board a plane at Houston’s Bush Intercontinental Airport and take off on the first commercial U.S. domestic flight to use Solazyme’s algae-based jet fuel. United Airlines will operate the flight, which will land at Chicago O’Hare International Airport a couple of hours later and is set to carry 189 passengers. The event is significant: While companies have spent years looking to scale next-generation biofuel products, few are producing fuels that can scale large enough to sell to the airline industry, let alone the auto industry. Solazyme’s jet fuel, dubbed Solajet, isn’t a widely commercialized product yet, but it has a few deals, including with the Navy and Australian carrier Quantas.
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The Seaward Solar PV210 PV installation tester provides a highly efficient and effective test and diagnostic solution for PV systems, carrying out all commissioning tests required by IEC 62446 and performing fast and accurate measurement of I-V curves in accordance with IEC 61829. With direct connection to individual PV modules or strings using the supplied lead sets, tests can be conducted easily and within a matter of seconds at the press of a single button.