Nanosolar Company has announced plans to build the world's largest solar cell production plant in California near San Jose. The objective is to produce 200 million solar cells per year, ie a cumulative power of 430 megawatts which could supply 300.000 homes.
Although silicon cells currently dominate almost all of the photovoltaic market, Nanosolar has chosen Copper Indium Selenium (CIS) technology for its solar cells. This technology has several advantages over conventional silicon cells. First, it makes it possible to overcome the shortage of silicon which is currently affecting the photovoltaic industry. Secondly, it is a thin film technology which requires only a few micro-m of active layers against several hundred for a crystalline silicon cell. Finally, the cell can be built on a flexible substrate. This opens the door to the manufacture of panels of a shape suitable for their use.
The progress made in recent years has enabled CIS cells to approach the yields achieved by polycrystalline silicon cells (around 12% yield). Nanosolar claims to have developed a manufacturing process that dramatically reduces the production costs of CIS cells, a factor that has hitherto held back the commercial development of these cells. Behind the company are Larry Page and Sergey Brin, the founders of Google. Sensing that solar is now on the rise, they decided to invest heavily in the development of Nanosolar. Left behind by Japan and Germany in the race to produce solar panels and increasingly concerned about their energy situation, the United States seems on the way to reacting and this project is an example, as is the recent program of solar incentive in California. It is also the opportunity to strengthen its position in an exponentially growing renewable energy market whose value is already 40 billion dollars and could reach 170 billion in 2015.