Sustainable Energy Blog

Cost has always been one of solar’s biggest problems. Traditional solar cells require silicon, and silicon is an expensive commodity (exacerbated currently by a global silicon shortage). What’s more, says Peter Harrop, chairman of electronics consulting firm IDTechEx, “it has to be put on glass, so it’s heavy, dangerous, expensive to ship and expensive to install because it has to be mounted.” And up to 70 percent of the silicon gets wasted in the manufacturing process. That means even the cheapest solar panels cost about $3 per watt of energy they go on to produce. To compete with coal, that figure has to shrink to just $1 per watt.

Nanosolar’s cells use no silicon, and the company’s manufacturing process allows it to create cells that are as efficient as most commercial cells for as little as 30 cents a watt. “You’re talking about printing rolls of the stuff—printing it on the roofs of 18-wheeler trailers, printing it on garages, printing it wherever you want it,” says Dan Kammen, founding director of the Renewable and Appropriate Energy Laboratory at the University of California at Berkeley. “It really is quite a big deal in terms of altering the way we think about solar and in inherently altering the economics of solar.”

http://www.popsci.com/popsci/flat/bown/2007/green/item_59.html