Outlook Brightens for Plastic Solar Cells

摘要

The global market for solar cells has been growing at more than 30% a year for much of the past decade. But to match the scale of coal or nuclear power anytime soon, the technology will have to do much better. Silicon cells, the premier solar technology, convert 15% to 20% of the energy in sunlight to electricity, and their price has been dropping steadily. But many industry observers worry that a price floor could be near, because the cells require expensive clean-room technology to manufacture. Thin films of copper, indium, gallium, and selenium are 15% efficient and cheap, but indium is in short supply. Cadmium-telluride thin films, which rely on rare tellurium, are in much the same boat. "The door is still open for a technology that gives you 15%, is cheap, and uses abundant materials," says Michael McGehee, a materials scientist at Stanford University in Palo Alto, California. It's an opening that makers of plastic solar cells hope to fill.