The most popular solar materials in use today are silicon and thin films made of CdTe (cadmium telluride) and CIGS (copper indium gallium selenide). While these materials have helped elevate solar to a major player in renewable energy markets, they are still limited by manufacturing challenges. Silicon is expensive to process and mass produce. Furthermore, it has become increasingly difficult to mine enough silicon to meet ever-growing consumer demand.
Thin films, while significantly less costly than silicon and easier to mass produce, would rapidly deplete our natural resources if these technologies were to scale to terawatt hours of annual manufacturing production. A terawatt hour is a billion kilowatt hours.
"We believe in a portfolio of technologies and therefore continue to support the commercial development of all photovoltaic technologies," Kammen said. "Yet, what we've found is that some leading thin films may be difficult to scale as high as global electricity consumption."
"It's not to say that these materials won't play a significant role," Wadia added, "but rather, if our objective is to supply the majority of electricity in this way, we must quickly consider alternative materials that are Earth-abundant, non-toxic and cheap. These are the materials that can get us to our goals more rapidly."
The team identified a large material extraction cost (
|Contact: Robert Sanders|
University of California - Berkeley