Guardian: Sixty years ago, the price of solar panels was astronomical. At a cost of $1,910 (1,350) per watt in todays money, the only practical use for them was in space on the US Vanguard 1 satellite, which launched in 1958.
But slowly and then precipitously the price of building a solar cell came down. Today it is less than $0.80 (0.55) per watt. The subsequent proliferation of panels (especially in Europe, China, US and India) has tracked along the dizzying curve that eventually lead to the market...