Thin-film solar panels may perform better in hot climates than rival crystalline products, based on half a year of data from the first Indian projects, an executive at the nation’s largest contractor on the developments said.
“The last six months for which we have data show that the performance of crystalline in hot climates is not as efficient as thin film,” said S.N. Subrahmanyan, senior executive vice president of construction at Larsen & Toubro Ltd. “Of course, it’s still early days. But that’s what we’re seeing.”
Concerns over use of thin-film panels were raised as First Solar Inc., the largest supplier, in February boosted provisions for warranties by $37.8 million due to potential for “increased failure rates in hot climates.” Developers and their lenders are seeking data on how technologies fare in warmer conditions as Europe, the biggest solar market, cuts renewables subsidies.
Traditional crystalline modules are silicon-based, while thin-film technology coats panels with materials such as cadmium telluride, copper indium gallium selenide and amorphous silicon.
Crystalline’s competitiveness matches thin-film when placed on trackers to rotate panels with the sun’s movement, boosting output as much as 20 percent, Subrahmanyan said in an interview.
Early results showed dust from desert conditions where most plants are built in Rajasthan and Gujarat states interferes with generation, while thin-film panels are easier to wash, he said.
The possibility panels will degrade at different rates at plants expected to last at least 25 years means it’s too early to say which product is better, he said by phone from Chennai.
First Solar, based in Tempe, Arizona, said high ambient temperatures may accelerate stress corrosion cracking in glass and other defects after analyzing panels returned under warranty and other data from markets including the southwestern U.S.