Solar innovator First Solar has just announced a new word record for solar cell conversion efficiency, for its cadmium-telluride (CdTe) thin film solar cell. That’s significant because CdTe solar cells can be made more quickly and cheaply than conventional silicon solar cells, bringing down the cost of solar power. The title of solar efficiency record holder is also significant politically because it was only last spring that First Solar was caught in the crosshairs, when certain members of Congress tried to manufacture scandals out of the Obama Administration’s support for the U.S. solar industry.
World Record for Solar Cell Efficiency
In tests confirmed by the National Renewable Energy Laboratory, First Solar’s CdTe solar cell achieved a conversion efficiency of 18.7 percent.
That’s far less than the efficiency of, say, an advanced concentrated solar system, but the relatively low cost of producing CdTe thin film solar cells makes up for a world of sin. First Solar’s manufacturing process can turn a sheet of glass into a solar module in less than 2-1/2 hours, which according to the company gives it the industry lead in energy payback time.
Thin film technology is also generally lighter and potentially more flexible than conventional solar cells, giving it a broader range of application. The trick is to tease out just a bit more efficiency from the technology to keep it commercially competitive.
First Solar has already been transferring its efficiency improvements into commercial production. Last year, the average efficiency of its production modules went from 12.2 percent to 12.9 percent, with the leading line achieving 13.1 percent.
By way of comparison, other commercial CdTe solar cells range in efficiency from about 10 percent to 12.4 percent.
We Built this Low Cost Solar Power!
Silicon is still by far the most-used material in photovoltaics but the Department of Energy has had its eye on CdTe at least since 1994, when NREL started up a public-private R&D partnership called the Thin Film Photovoltaic Partnership Project.
The Thin Film Project focused on three types of promising thin film materials. It included small companies for pilot projects, but for commercial production it assigned one major thin film manufacturing company to each of the three materials.
One of those companies was First Solar, making it the only major CdTe manufacturer that the Thin Film Project has focused on since 2003 (yes, from the early years of the Bush Administration).
The whole point of the Thin Film Project was to help the U.S. solar industry regain its competitive edge in the global solar power market. When the project first started, thin film was an extremely expensive, rarefied technology that was used primarily in space programs. It achieved marvelous results under the Bush Administration. From 2003 to 2008, U.S. thin film manufacturing capacity grew from about 10 MW (megawatts) to more than 250 MW.
By 2009, at the start of the Obama Administration, First Solar had emerged as an all-out success story. This is NREL’s take on it:
“…an innovator in thin-film solar technology has grown from a start-up company to become the world’s largest manufacturer of solar modules. First Solar, Inc. now manufactures its cadmium telluride (CdTe) solar modules throughout the world, and in 2009, it became the first solar manufacturer in the world to produce more than 1,000 megawatts (MW) of solar panels in a single year. That’s enough solar modules to equal the generating capacity of an average-sized nuclear power plant.
SunShot and Low Cost Solar Power
Working toward the same goal of global competitiveness, with climate change and national defense thrown in for good measure, in 2011 President Obama folded the Thin Film Project into a far more comprehensive public-private program called the SunShot Initiative.
The goal of SunShot is to make solar power and other forms of alternative energy as cheap and accessible as fossil fuels, not only through transformational research but also by lowering the cost of manufacturing and installation.
That’s not exactly a new idea, by the way. SunShot’s precursor, the Advanced Energy Initiative was launched by President Bush in his 2006 State of the Union Address, with the same goals of addressing national security and environmental issues as well as global competitiveness. His words could have just as easily been spoken by President Obama today:
“Keeping America competitive requires affordable energy. And here we have a serious problem: America is addicted to oil, which is often imported from unstable parts of the world. The best way to break this addiction is through technology.”
Image: First Solar logo courtesy of First Solar, Inc.
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.