A Chinese solar giant goes bankrupt, and why that's a good thing

Once the world's largest solar panel maker, Suntech Power, has finally been forced into bankruptcy. The company has been running out of cash for months, defaulted on a loan payment recently, and has now become the biggest casualty yet of the coming consolidation of the global solar industry.

This week eight Chinese banks asked a court to find Suntech subsidiary Wuxi Suntech insolvent and to allow it to begin restructuring. Suntech responded to the court and said it would not object. The New York Times reported that the bankruptcy is "expected to lead to a takeover of the Wuxi operations by Wuxi Guolian, a financial conglomerate controlled by the city government of Wuxi."

The solar market has seen an oversupply of solar panels and plummeting prices for those panels for over two years now. Two thirds of solar cells are made in China, where the Chinese government has given Chinese solar makers access to large low cost loans. The oversupply and drop in prices has led to huge solar manufacturers like Q-Cells to startups like Solyndra and Abound Solar to file for bankruptcy.

Suntech solar panels

Suntech may be the largest to date, but it won't be the last solar maker to crash. As MIT Tech Review put it earlier this week: "hundreds of solar companies need to fail to help bring the supply of solar panels back in line with demand."

The weeding-out process will help slow the fall in solar panel prices and allow demand to rise back up again. Down the road the re-balancing will enable these companies to continue to invest in more efficient cells and new innovations, which will bring down the cost of solar through technology even more. Another 180 solar panel makers could reportedly disappear by 2015 due to consolidation.

At the same time, Suntech's woes partly come from a financial scandal. The company got in trouble with a fund it controlled that financed solar power plant development in Europe.

Of course, it's not all positive that Suntech has declared bankruptcy. As Ucilia Wang wrote for us last week:

The drama presents an ugly turn for a company that was solid and took technology and market risks to grow. . . Chinese companies in general had been known more as mass producers rather than innovators. . . Suntech's decline also leaves a depressing note in the efforts by the federal and local governments to expand solar manufacturing in the U.S.

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• Cleantech and investment in 2013
• After Solyndra: analyzing the solar industry
• Flash analysis: lessons from Solyndra's fall

http://gigaom.com/2013/03/20/a-chinese-solar-giant-goes-bankrupt-and-w

2012 was a record-breaking year for solar panels in the US

Last year there was a record-breaking 3.3 gigawatts worth of solar panels - or 16 million individual solar panels - installed in the U.S., making solar power the fastest-growing energy source domestically. That's according to a new report from the Solar Energy Industries Association and GTM Research. In comparison, a large nuclear or coal plant can generate about a gigawatt, so there was the equivalent of three of these types of large power plant ...

http://gigaom.com/2013/03/14/2012-was-a-record-breaking-year-for-solar

MIT team outlines path to low-cost solar-to-fuels devices; the artificial leaf

(A) Block diagram for providing power to an electrochemical cell (EC), using a photovoltaic (PV) device via direct coupling, as well as (B) experimental examples, including an interdigitated contact geometry that minimizes solution resistance. Source: Winkler et al. 2013 Click to enlarge.

A team of researchers at MIT has described a framework for efficiently coupling the power output of a series-connected string of single-band-gap solar cells to an electrochemical process that produces storable fuels. The open access paper, published in the Proceedings of the National Academy of Sciences (PNAS), offers a roadmap for direct solar-to-fuels devices.

The new analysis follows up on 2011 research that produced a proof of concept of an artificial leaf-a small device that, when placed in a container of water and exposed to sunlight, would produce bubbles of hydrogen and oxygen. (Earlier post.) The new work outlines a research program to improve the efficiency of these systems, and could quickly lead to the production of a practical, inexpensive and commercially viable prototype.

The original demonstration leaf in 2011 had low efficiencies, converting less than 4.7% of sunlight into fuel. The team's new analysis shows that efficiencies of 16% or more should now be possible using single-bandgap semiconductors, such as crystalline silicon, or 18% for gallium arsenide cells.

Such a system would use sunlight to produce a storable fuel, such as hydrogen, instead of electricity for immediate use. This fuel could then be used on demand to generate electricity through a fuel cell or other device. This process would liberate solar energy for use when the sun isn't shining, and open up a host of potential new applications.

This article extends the construction of direct solar-to-fuels devices, such as the artificial leaf based on crystalline silicon. Because a single Si junction has insufficient potential to drive water splitting, it cannot be used for direct solar-to-fuels conversion. This paper performs an equivalent circuit analysis for multiple series-connected devices. The predictive utility of the model is demonstrated in the case of water oxidation at the surface of a Si solar cell, using a cobalt-borate oxygen evolving catalyst. Considering recent cost reductions of Si solar cells, this paper offers a path to the construction of low cost solar-to-fuels devices.

-Winkler et al.

Authors of the paper are MIT associate professor of mechanical engineering Tonio Buonassisi, former MIT professor Daniel Nocera (now at Harvard University), MIT postdoc Mark Winkler (now at IBM T. J. Watson Research Center) and former MIT graduate student Casandra Cox (now at Harvard).

The device combines two technologies: a standard silicon solar cell, which converts sunlight into electricity, and chemical catalysts applied to each side of the cell. Together, these would create an electrochemical device that uses an electric current to split atoms of hydrogen and oxygen from the water molecules surrounding them.

The goal is to produce an inexpensive, self-contained system that could be built from abundant materials. Nocera has long advocated such devices as a means of bringing electricity to billions of people, mostly in the developing world, who now have little or no access to it.

The key to obtaining high solar-to-fuel efficiencies is to combine the right solar cells and catalyst-a matchmaking activity best guided by a roadmap. The approach presented by the team allows for each component of the artificial leaf to be tested individually, then combined.

We have outlined a framework for integrating single-absorber solar cells as power sources for electrochemical processes and understanding the efficiency-limiting elements. The steady-state efficiency of coupled PV-EC systems depends on the individual efficiency of each system, but it also depends critically on the efficiency of coupling the two systems. When coupling the two systems directly, by performing each half-reaction on a terminal of the PV device, the coupling efficiency can be modeled using a steady-state equivalent circuit. Additionally, the efficiency of the coupled PV-EC system can be determined given the behavior of each subsystem. We validate this model by correctly predicting the J-V characteristics of a PV-assisted OER to within <10 mV. A key result of our analysis is that even when using commercially available Si solar cells, SFE over 15% is achievable provided the design yields very low solution resistance. We have proposed strategies for meeting this challenge.

-Winkler et al.

The voltage produced by a standard silicon solar cell, about 0.7 volts, is insufficient to power the water-splitting reaction, which needs more than 1.2 volts. One solution is to pair multiple solar cells in series. While this leads to some losses at the interface between the cells, it is a promising direction for the research, Buonassisi says.

An additional source of inefficiency is the water itself-the pathway that the electrons must traverse to complete the electrical circuit-which has resistance to the electrons, Buonassisi says. So another way to improve efficiency would be to lower that resistance, perhaps by reducing the distance that ions must travel through the liquid.

While the solution resistance is challenging, Cox says, there are "some tricks" that might help to reduce that resistance, such as reducing the distance between the two sides of the reaction by using interleaved plates.

James Barber, the Ernst Chain Professor of Biochemistry at Imperial College London, who was not connected with this work, says, "It is generally agreed that for an effective technology to emerge, the efficiency of the device must be 10 percent or more." The MIT team's work suggests such devices "can provide efficiencies as high as 15 percent. This level of energy conversion is considered very good and practical."

Barber adds that a next step, demonstrating these improvements in a functioning device, is crucial: "It is very important to construct a working system which has a large surface area and operates with solar energy under open field conditions for a long period of time, as is done with the testing of solar cells." If this can be achieved, he says, "the construction of robust and efficient solar-driven modules which produce hydrogen from water on a large industrial scale would have considerable impact on human society."

The work was supported by the National Science Foundation, the Air Force Office of Scientific Research, the Singapore National Research Foundation through the Singapore-MIT Alliance for Research and Technology, and the Chesonis Family Foundation.

Resources

• Mark T. Winkler, Casandra R. Cox, Daniel G. Nocera, and Tonio Buonassisi (2013) Modeling integrated photovoltaic-electrochemical devices using steady-state equivalent circuits. PNAS doi: 10.1073/pnas.1301532110

• Steven Y. Reece, Jonathan A. Hamel, Kimberly Sung, Thomas D. Jarvi, Arthur J. Esswein, Joep J. H. Pijpers, and Daniel G. Nocera (2011) Wireless Solar Water Splitting Using Silicon-Based Semiconductors and Earth-Abundant Catalysts. Science doi: 10.1126/science.1209816

http://www.greencarcongress.com/2013/03/winkler-20130305.htm

Struggles continue for thin film solar startups, Nanosolar latest with layoffs

Super cheap solar panels being churned out of China continue to put pressure on the startups looking to build the next generation of thin-film solar cells. According to two reports (Dana Hull, and Greentech Media) thin-film solar startup Nanosolar has done a round of layoffs, which could be as substantial as 75 percent of its staff.

Oh how times have changed - one of the first stories I did for GigaOM's cleantech channel was "10 questions for Nanosolar CEO Martin Roschiesen" in the summer of 2007. Back then Roschiesen told me the company was starting pilot production that year and had raised enough money to make it profitable. In 2008, the company was valued at $2 billion.

Fast forward to 2012, and Nanosolar raised $70 million from investors, reportedly at a pre-money valuation of $50 million. Aeris Capital, a fund that manages finances for SAP founder Klaus Tschira, partly funded that round as a way to pick up solar assets on the cheap. Other investors in that round included OnPoint Technologies, Mohr Davidow Ventures, Ohana Holdings, and Family Offices. Nanosolar has taken in at least $450 million since its start in 2002.

Nanosolar makes thin solar panels out of a material called copper-indium-gallium-selenide (CIGS). At one time in Silicon Valley, CIGS was the great white hope - Solyndra, Heliovolt, Miasole, and others raised hundreds of millions of dollars to build the next-generation of solar tech. But the price of silicon-based solar dropped dramatically and made the economics of selling more expensive CIGS panels much more difficult. Some of these companies have gone bankrupt, done major layoffs, retrenched or been sold off in fire sales.

Solar Frontier, part of Japan's Showa Shell, is one of the only companies to reach scale with its CIGS solar panels. The company completed a 900 MW factory in late 2010 and brought all of its production lines into commercial production mode by the summer of 2011.

Nanosolar could end up being acquired for cheap from international investors. South Korean and Chinese power conglomerates have particuarly shown interest in investing in and buying discounted U.S. clean power assets. Or there's always the Solyndra route - a very public, abrupt bankruptcy.

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• The opportunities for the Internet and clean power
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http://gigaom.com/2013/02/19/struggles-continue-for-thin-film-solar-st

Volkswagen inaugurates 9.5 MW solar park at Chattanooga plant in US; key element of VW Group's strategic sustainability targets

The 9.5 MW solar park at Chattanooga is owned and operated by Silicon Ranch; VW has signed a 20-year power purchase agreement. Click to enlarge.

Volkswagen inaugurated its largest solar facility in the world-also the largest solar facility operated by an automaker in the US-at its plant in Chattanooga, TN, which produces the Passat model for North America. The Volkswagen Chattanooga Solar Park has a peak output of 9.5 MW. The power will be used directly in production; solar power will provide up to 12.5% of the electric power required in full-capacity operation and 100% of demand when the plant is not in production.

The new solar park is an integral part of Volkswagen's worldwide sustainability strategy, which includes generating more power within the Group from renewable energy sources, said Volkswagen Group Officer for the Environment, Energy and New Business Areas, Wolfram Thomas.

The Volkswagen Group has set itself the goal of becoming the world's leading automaker in environmental terms by 2018. At the Geneva Motor Show in 2012, we stated specific, ambitious targets for our products, production and the group. We have adopted the most comprehensive approach possible. Clean cars from a clean factory and an attitude to the environment that aims to change the way of people's thinking.

Financially, we have laid the foundation for profitable sustainable growth. We have defined consistent CO₂ reduction for the protection of the climate as a binding objective for the group. To do so, we have adopted a diversified strategy throughout the world. We are German, and we are thorough. All our 100 plants are to be environmentally optimized. All our plants are to become 25% more environmentally compatible.

The main focus is to include increasingly efficient production as well as increasing energy supplies to all plants. VW is also an energy supplier that generates a growing share of the power needed for the group. We are increasing the share of green energy in a modular way. The new solar park here is a further green module in this strategy, and will make production at the plant more sustainable in the future.

-Wolfram Thomas, at the solar park launch event

In Germany, the Volkswagen Group provides 62% of its own power, with more to come, Thomas said. Czech-based Skoda generates 73% of its power, with a renewable share of 23%. SEAT in Spain, with an 8MW solar array, generates 56% of its own power. (Thomas was Executive Vice-President for Production of SEAT before assuming the Group environmental role.)

Volkswagen sustainability targets. At the Geneva show in 2012, Prof. Dr. Martin Winterkorn, Chairman of the Volkswagen Group Board of Management, laid out the group's sustainability targets. These included:

• The Volkswagen Group will be investing ‚Ǩ62.4 billion (US$83.4 billion) worldwide plus an additional ‚Ǩ14 billion (US$19 billion) in China during the period to 2016. More than two-thirds of this investment program will be spent directly or indirectly on ever more efficient vehicles, powertrains and technologies as well as environmentally compatible production at Group plants.

• CO₂ emissions by the European new vehicle fleet will be reduced by some 30% during the period from 2006 to 2015-emissions will be below the threshold of 120 grams CO₂/km for the first time by 2015.

• Every new model generation will on average be 10 to 15% more efficient than its predecessor.

• There is to be a 25% improvement in the environmental compatibility of production in the Volkswagen Group by 2018-i.e., 25% less energy and water consumption, waste and emissions.

• 40% reduction in greenhouse gas emissions associated with production-related energy supplies by 2020.

• Some ‚Ǩ600 million is to be invested in expanding the use of renewable energies such as wind, solar and hydroelectric power. (At the launch event at Chattanooga, Thomas put the figure at $850 million, or ‚Ǩ636 million.)

The Chattanooga Solar Park. The solar installation at Volkswagen Chattanooga confirms the awarding of the LEED Platinum certification to VW by the US Green Building Council in late 2011. At that time, the Building Council called the Chattanooga manufacturing facility "the world's greenest auto plant" and noted it was the first automotive manufacturing plant in the world to receive the top LEED certification. Today, the Chattanooga plant remains the only auto plant worldwide to earn the LEED Platinum certification.

The Volkswagen Chattanooga Solar Park occupies 33 acres, or half of the 66-acre land parcel adjacent to VW's plant. The solar park contains 33,600 polycrystalline solar panels (each rated at 285 watts) from JA Solar designed to produce 13.1 gigawatt hours of electricity per year-equivalent to the energy consumed annually by around 1,200 homes in the area. The modules are mounted on a Unirac racking system, with a fixed angle at 25° tilt.

Ten SMA inverters and 5 transformers (rated at 1500 KVA each) convert the 9.58 MW of DC power to 7.6 MW of AC power connected to VW's substation. There are 3,360 panels per inverter made up of 168 strongs at 20 modules per string.

Silicon Ranch, which develops and operates solar energy solutions tailored to meet its customers' needs, will own the solar park and sell the electricity to Volkswagen under a 20-year Power Purchase Agreement (PPA). Phoenix Solar Inc., the US subsidiary of Phoenix Solar AG, provided engineering, procurement and construction (EPC) services in building the solar park.

Mobilization took place in July 2012, and power started to be generated in November 2012.

Volkswagen Chattanooga. Volkswagen has invested about $1 billion in the facility. In December 2011, the plant received a platinum certification from the U.S. Green Building Council's (USGBC) Leadership in Energy and Environmental Design (LEED) green building certification program.

Aspects of the plant that earned LEED recognition include:

• Superior insulation provided by six inches of mineral rock wool, resulting in 720,000 Kilowatts per year savings.

• Green power from the local hydroelectric dam.

• Use of LED lighting on the exterior results in 68% less energy used, up to 262,500 kWh per year and a reduction in light pollution. (T5 fluorescents are use don the inside.)

• Rainwater collected and reused to flush toilets and cool the welding machines.

• White roof membrane is highly reflective, minimizing heat island effect by up to 50¬∞F.

• Natural flowing creeks to capture heavy rains and restore a natural habitat.

• Low-flow water fixtures and no-touch sensors throughout the plant reduce water usage by 30%.

• Plant was built on a brownfield property (former TNT manufacturing site) with no destruction of untouched nature. Protected 100 ft. wide creeks and wetlands were established to create natural habitats with low impact on natural habitats.

The adjacent Volkswagen Academy was also certified by USGBA as a Platinum LEED facility. The primary purpose of the Volkswagen Academy is to prepare new employees for work at the Volkswagen plant. In conjunction with Chattanooga State and Tennessee Tech, the Academy also offers an Industrial Technology degree and an apprenticeship program.

The Chattanooga plant is being used as a blueprint for three other Volkswagen plants: two in China, and one in Mexico.

Volkswagen hosted Green Car Congress for the inauguration of the solar park.

http://www.greencarcongress.com/2013/01/vw-20130124.htm

China is buying up a third of the world's solar panels

China has long been the world's supplier of low cost solar panels, and now it's a major market for them, too. According to research firm NPD's SolarBuzz report, in the last quarter of 2012 China bought up 33 percent of the world's solar panel supply.In contrast, two years prior China accounted for less than 10 percent of the world's solar panel sales. The shift is a combo of slowing sales in Europe, and strong subsidies for solar panels in China. ...

http://gigaom.com/2013/01/22/china-is-buying-up-a-third-of-the-worlds-

Why crowd funding could disrupt how solar power is created

If you're an avid Kickstarter backer, or even have seen Kickstarter's latest 2012 stats, then you're well-versed in the power of crowd-funding. Kickstarter recently said that 10 percent of the films at Sundance are Kickstarter-funded, and in 2012 over 2 million people pledged close to $320 million to successfully fund over 18,000 Kickstarter projects on the site. Can clean power projects - like solar panel rooftop installations and even wind farm ...

http://gigaom.com/2013/01/11/why-crowd-funding-could-disrupt-how-solar

Solar Mosaic fully crowd funds its new solar projects in less than 24 hours

On Monday Solar Mosaic officially opened up its solar crowd-funding site to residents in California and New York as well as accredited investors. And by Tuesday, the site had fully funded all three of the new projects that were made available to public investors, which will install solar panels on affordable housing projects in Corte Madera, Calif., Salinas, Calif., and San Bruno, Calif. Solar Mosaic still has one solar project available at this ...

http://gigaom.com/2013/01/08/solar-mosaic-fully-crowd-funds-its-new-so

Solar Mosaic turns "the Kickstarter of solar" into a way to make money

Updated: At 9AM (PST) on Monday, the Kickstarter of solar, Solar Mosaic, will officially open its site to residents of California and New York, as well as accredited investors, looking to make money by investing in solar panel roof projects. For months (at least since last summer), Solar Mosaic has been enabling a small amount of investors to experiment with investing in, and earning money from, the returns from solar roofs, but this is the company's big public launch.

The company was founded back in October 2010, and I wrote one of the first profiles of Solar Mosaic in October 2011. It took the startup a little over two years to test out its beta Kickstarter-style platform and become registered to share securities with the public. Last year, it got a vote of confidence from the crowd funding bill. The company is backed by Spring Ventures.

For potential investors, solar roofs can provide a low-risk return - anywhere between 4 and 12 percent on an investment - kind of like investing in a mutual fund. Building owners lease solar panel systems and enter into a contract for a fixed, low electricity rate, commonly over about two decades. Solar Mosaic organizes the crowd-funding to get the solar rooftop installed, and works with a solar lease provider like Sungevity. Once the project gets crowd-funded, the rooftop solar panel installation process starts.

Solar loans are backed by a revenue-producing asset (electricity) and the building owners pay for the solar electricity monthly in the same way they have been paying their monthly utility bill. The buildings owners aren't all that likely to default on their electricity payments, and the costs, timelines and returns for solar panels are pretty transparent as the technology has become increasingly commoditized. Another company that has created a site for crowd-funded solar is SunFunder.

Solar Mosaic says its first investments will offer a 4.5 percent annual return, including servicing fees, with a nine-year term. The company says it is offering "a better expected yield than most investment products available to the general public." The company will hold a press call at 10 PST, and we'll update this story after the call.

Update:

There are three new solar projects that residents of California and New York can put money in as of Monday morning, including solar panels on the roofs of affordable housing projects in Corte Madera, Calif., Salinas, Calif., and San Bruno, Calif.

The company said on a media call that the SEC approval process took longer than expected because what Solar Mosaic has been working on is so novel, and because the SEC also has been slow on implementing the Jobs Act.

See our previous stories on Solar Mosaic:

• Solar Mosaic, the Kickstarter of solar aims high
• The Kickstarter of solar could make you money starting this Summer
• How crowd-funding could revolutionize solar
• The clean energy revolution will be crowd funded

http://gigaom.com/cleantech/solar-mosaic-turns-the-kickstarter-of-sola

Deep sea bacteria could provide breakthroughs for solar panels

Bacteria that live almost a mile under the surface of the ocean, where light is scare, have adapted biological ways to harness tiny amounts of light very efficiently, and in some cases can use photosynthesis to convert 100 percent of the light they find into electricity. In contrast a typical solar panel commonly converts around 15 percent of sunlight into electricity.

Now researchers at the University of Cambridge are studying the light-harvesting proteins of the deep sea Green Sulfur Bacteria to see if they can provide breakthroughs for solar energy and other electricity devices. The research is in an area called quantum biology, and the scientists say it falls outside of 'classical' physics, and into quantum physics.

Organisms that do photosynthesis use a network of pigments held in place by protein structures, or what scientists call pigment-protein complexes, where electrons are harvested. In many organisms as the electrons move through these systems they lose energy. But in the Green Sulfur Bacteria they are able to move electrons through their photosynthesis system to the point of harvest without losing that energy on the way.

Raising the efficiency of solar cells (which make up solar panels) is very important work for solar companies. The higher the efficiency of the cells, the more electricity can be created by the panel and the fewer cells and panels needed.

Solar companies have been working diligently on these innovations in recent years, as the basic low efficiency solar panels become more and more commoditized. For example, Alta Devices, makes cells that can convert a whopping 28.8 percent of sunlight into electricity. But those types of cells are far more expensive than the standard cells, and many are still in the research and development phase.

http://gigaom.com/cleantech/how-deep-sea-bacteria-could-provide-breakt

Post-IPO, SolarCity plans to ratchet up solar roofs to 250MW in 2013

Following an IPO that saw solar installer and financier SolarCity's shares rise almost 50 percent on its first day of trading, the Elon Musk-backed company now says it has a robust growth plan in place for its solar roofs in 2013. This year, SolarCity says it plans to install 250 MW of solar roof capacity, up from 156 MW of solar roofs capacity installed in 2012. To put that in perspective, the entire solar panel industry in the U.S. is estimated ...

http://gigaom.com/cleantech/post-ipo-solarcity-plans-to-ratchet-up-sol

Building integrated solar panels set to boom over the next 5 years

Solar panels that can be integrated right into rooftops and the walls of buildings is a new market that is set to grow dramatically over the next five years, according to a new report from Pike Research, a part of Navigant. The report says that the energy capacity of solar panels that are built into the structures of buildings will grow from 400 MW in 2012 to 2.25 GW in 2017, or a five-fold increase worldwide.

The solar industry calls this technology "building-integrated photovoltaics" or BIPV. Some of this new capacity will come from thin film solar panels that will be able to be printed right onto building materials, like shingles, steel roof casing, and windows. A lot of companies have been gunning for this market, and many have been held back by the difficult solar production market in 2012. There are at least 53 companies working on this tech, says Pike.

Dow launched its solar shingle product about a year ago in Colorado and began selling them in California and Texas earlier this year. Miasole, which was sold to China's Hanergy in a firesale, had been working on BIPV, as had Arizona-based Global Solar Energy, which recently started layoffs and curbed manufacturing. Dozens of solar module makers went bankrupt or struggled in 2012, due to an oversupply and rock bottom prices.

But the BIPV market could provide a bright spot, says the Pike report. The value of the BIPV market could quadruple over the next five years from $606 million in 2012 to $2.4 billion in 2017. The market will also be encouraged by a rebound of home sales and construction.

http://gigaom.com/cleantech/building-integrated-solar-panels-set-to-bo

5 charts that show the massive growth of solar in 2012 [charts]

Despite solar manufacturers' struggles with bankruptcies and an oversupply problem this year, 2012 actually witnessed a dramatic growth in the world's use of solar power. In particular the amount of solar panels installed on rooftops in the U.S. soared in recent quarters, helped by new financing models by companies like SolarCity and rock-bottom silicon prices - the main ingredient in solar panels.

In these 5 charts, we track the growth of solar power:

1). The amount of solar energy produced in the U.S. has risen 500 percent in 2012 alone, according to the Energy Information Administration.

2). The increase in solar production has to do in part with the growth of solar panel installation and capacity in the U.S. Solar panel installation is expected to rise nearly 70 percent this year, according to the Solar Energy Industry Association's third-quarter report.

3). SolarCity's IPO in late 2012 was one of the rare success stories for solar and cleantech startups. While some solar stocks have taken hits this year - due to over supply and super low prices - SolarCity was able to go public and its stock rose 50 percent on its first day of trading. The company, which finances and installs rooftop solar panels, originally priced its shares lower than expected, but the company's stock price remains relatively high.

4). The price of silicon - the main material in solar panels - has dropped by half in less than two years, making solar panels cheaper to produce and to buy. The low prices, in turn, have fueled the growth of solar panel installations.

5). As is common with new commodity industries that grow rapidly, solar cells and panels are now so cheap to produce and make that there's an oversupply problem. According to SEIA, there's now 70 GW worth of solar module manufacturing capacity, but the current world capacity for solar modules is only 31 GW.

http://gigaom.com/cleantech/5-charts-that-show-the-amazing-growth-in-s

A solar funnel that could lead to more efficient cells

The reality of solar panels is that those on the market today aren't very efficient - most of the solar cells, which make up an entire panel, convert less than a fifth of the sunlight into electricity. But researchers at MIT said on Monday they have come up with a funnel-like design that will manipulate the incoming electrons to engineer more efficient solar cells.

The research, just published in the journal, Nature Photonics, used computer modeling to look at how to stretch the semiconductor molybdenum disulfide to change its physical properties to make use of a broader spectrum of sunlight than what silicon, the most common solar cell material, can manage today. Whether the design will work as well in real life will require further research.

Improving cell efficiency is important for lowering the cost of producing solar electricity. One way to do that is to extract more energy from the same amount of materials. That also will reduce the amount of land needed to generate the same amount of electricity. As it stands, photovoltaic power plants are more land-intensive compared with fossil fuel power plants with a similar energy output. Building solar farms on large swath of land has prompted fierce debates over their environmental impact on wildlife and prompted developers to agree to set aside wildlife corridors in exchange for permits or to avoid lawsuits.

What some scientists have been working on is to manipulate the band gap in a material. A band gap describes the amount of energy that electrons need to move around and generate electricity. If you can manipulate band gaps, then you can control the amount of electricity produced. Band gap engineering is not a new concept and is already used by solar cell developers and academic researchers in their search for more efficient solar cell designs.

What the MIT researchers proposed is more novel: strain a material to create specific and varying band gaps within a single material to capture different portions of the light spectrum. They imagined creating that strain by using a microscopic needle to poke at the material down the center and create that funnel. The pressure on the needle would cause different degrees of strain and band gaps.

Knowing how to stretch a material is only part of the solution. Finding materials that can withstand the pressure is another hurdle. Conventional solar materials would break or warp undesirably under the straining process proposed by the research. But there is a more recently minted class of ultra-strength materials" that could be suitable. MIT researchers settled on molybdenum disulfide.

The research, which received support from U.S. and Chinese institutions, is only a start in exploring the idea of using ultra-strength materials to engineer more efficient solar cells. The MIT research team, which includes Ju Li, Xiaofeng Qian and Cheng-Wei Huang, hopes to conduct lab work to verify the results of their computer modeling. Ji Feng of Peking University in China rounds up the research team.

http://feedproxy.google.com/~r/OmMalik/~3/3satxURrg0k/story01.htm

http://gigaom.feedsportal.com/c/34996/f/646446/s/25fb8f66/l/0Lgigaom0N0Ccleantech0Ca0Esolar0Efunnel0Ethat0Ecould0Elead0Eto0Emore0Eefficient0Ecells0C/story01.htm