A team of German researchers has nudged aside a U.S. record for thin film solar efficiency, previously held by the National Renewable Energy Laboratory at 19.9%. The new German solar conversion efficiency record of 20.1% is for CIGS thin film solar technology, which is based on a compound of copper, indium, gallium, and selenium. According to a report in Electro IQ, the team from the Centre for Solar Energy and Hydrogen Research achieved the result in laboratory tests, using a co-evaporation process that is scalable to commercial production – at least in theory.
Meanwhile, a U.S.-Korean research team based at Oregon State University is on to a new low cost process for manufacturing thin film photovoltaic cells based on a variant of CIGS, copper indium diselenide (CIS). Put the two together and we may be taking yet another step forward in making sustainable solar energy cost-competitive with fossil fuels.
A Cheaper Way to Make Thin Film Solar Cells
The conventional manufacture of thin film solar cells is based on application processes that involve sputtering, evaporation or electrodeposition. These are either relatively time consuming, require high cost chemicals, involve expensive vacuum equipment, or have spotty quality control. The Oregon State team claims that its method, which deposits solar absorbers on a substrate, is cheaper and faster, without the use of toxic chemicals.
Green Manufacturing and the New Solar Future
Oregon State’s emphasis on a safer production process is just one example of a growing movement by the solar energy industry to focus on non-toxic chemicals and other materials. Magnolia Solar offers another example, with a thin film technology that involves nanoscale crystals of nontoxic materials. As for reducing the cost of solar manufacturing, that trend is evolving on a number of fronts including cheap “solar paint” and even a low cost solar technology inspired by Shrinky Dinks. The future may look dim for offshore oil drilling but it sure is looking brighter for clean, sustainable solar energy.
Image: Sun shines through cracked glass by creativity 103 on flickr.com.
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+.