[jyl]

Traditional solar cells are made from polysilicon wafers (currently global capacity is still tight) in a semiconductor-like process (so substantial capital cost for clean room and equipment). Thin-film solar cells are considerably less expensive but also less efficient. The cost curve for both is declining pretty rapidly, in a few years the $/watt of the panels will be substantially lower, partly from higher panel efficiency and manufacturing efficiency, but also because a lot of new polysilicon capacity is coming online in the next 2 years.