High performance single-crystalline solar cells have historically been expensive, mostly due to the materials used in the manufacturing process. A Santa Clara, CA, startup company, Crystal Solar, has developed an innovative process of manufacturing solar cells that have the same efficiency but cost a lot less.
Concretely, their technology lies on the fact that silicon solar cells waste about 50% of the material when they get built, through the imperfections in the sawing process. Crystal Solar’s technology, though, doesn’t use mechanical sawing, but rather building the silicon substrate directly from a gas and then depositing it in a controlled vacuum atmosphere.
The technology is called epitaxial growth, and is not something new for the scientific community. Still, thy haven’t been able so far to apply the technology to solar cells, although it had been used to make microchips for decades. Crystal Solar has rebuilt the machinery from the ground up.
The company has realized that the best width for a solar cell’s silicon substrate is about 50 micrometers. Any thinner than that and it’s no longer efficient. They claim that their method can make solar cells with he same efficiency but with half or even one third of the materials you’d normally need.
NREL (the National Renewable Energy Laboratory) has awarded Crystal Solar with $4 million over the next year and a half, to expand their research in this field and to build a production facility by the beginning of 2013.
[via technology review]
