Solar Power
Commercial solar power has been around since the 1970s, but it's only just now starting to become affordable enough to make a real impact on energy use. After a years-long supply shortage, prices have plunged in the last two years. Solar production boomed after manufacturers scrambled to add capacity during the shortage, and that led to a huge boost in supply right when the growth in solar installations began slowing thanks to the recession and slashed government subsidies.