One problem for the emerging technology is cost, even in the aftermath of a sharp fall in solar panel prices, following a global glut of the main raw material, solar-grade silicon.
Two Japanese companies are the leading producers of silicon wafers, the raw material used to make computer chips, accounting for more than 60 percent of the world's supply.
有两家日本公司是全球领先的硅晶片生产商，硅晶片用于制造电脑芯片，占了全球供应的60%还多。
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Until recently, however, Silicon Valley did not take much interest in the alternative use of its principal raw material.