Thin Film Solar Panels Take A Giant Leap Toward Affordable Renewable Energy

solar.coolerplanet.com
April 01, 2010

Two drawbacks to solar power were cost and the bulk of the panels, but newer panels, called thin-film solar panels are lowering the cost of solar and allowing new types of solar panels to be made. Some are flexible and can either be rolled up or formed into roof tiles, so it's hardly noticeable that you're powering your home with the sun!

Over the past decade continual breakthroughs have made the manufacture of thin-film solar panels less expensive while improving their efficiency in producing electricity. Some are even capable of rivaling the power produced by their heavy silicone counterparts. Abound Solar, a Colorado based company, has claimed they can produce thin-film photovoltaics at $1 per watt. That makes it cost-competitive with fossil fuels. By comparison, crystalline silicone panels cost roughly $4 per watt to make.

Most home installed systems convert 10% or 11% sun's energy into electricity. But it ranges between 8% and 20%, according to the National Renewable Energy Lab (NREL), which researches and tests new photovoltaic technologies. Traditional crystalline silicone photovoltaic panels (the ones on most homes) are more costly, partly because the silicone used in making them can comprise 40% to 50% of the total cost of the panel. Still, these silicone panels are the most efficient panels and can convert up to 20.3% of the sun's rays. Some thin-film photovoltaics are now reaching that level.

The lab set a world record in 2008 when it made a thin-film solar panel that was 20% efficient using a Copper Indium Gallium diSelenide (CIGS) semiconductor. The other promising technology is cadmium-telluride (CdTe), which has converted solar power at up to 16.8% efficiency. NREL scientist Ingrid Repins foresees that using the 20% efficient formula as the base, companies will be able to roll out kilometer-long sheets of solar cells that achieve 16% efficiency, while using the cheapest materials and emphasizing speed. Repins explains that the cost-savings achieved when the panels reach an average 16% efficiency is huge. The more efficient cells won't need to be as large and use less material. Both of which lower manufacturing and materials cost. And the smaller size also lowers installation costs, she says.

Since it takes less energy to make thin-film photovoltaics they should be able to make less-expensive solar panels for utility and residential uses, according to NREL. These new photovoltaics will be on the market soon. But thin-film solar is already available. Companies like Uni-Solar and SRS Energy are making thin-film solar panels in the form of roof shingles and tiles. And those backpacks and portable solar panels you buy to power your mobile devices while on the go are also thin-film photovoltaics.

Big companies are lining up to start producing thin-film photovoltaics. General Electric recently stopped making hard silicone panels and will begin producing cadmium telluride panels, based on PrimeStar Solar Inc.'s technology, a company GE owns most of.

The company plans to introduce the new panels in 2011. And it plans to be a high-volume producer of the new panels. "After having completed an exhaustive survey of the PV landscape, we determined that thin films were the optimum path for GE," said Danielle Merfeld, GE's solar research and development leader. The company thinks the cadmium telluride technology will allow it to produce low-cost, high efficiency solar cells.