Today saw good news for solar power, as Bloomberg's New Energy Finance group predicted 2013 would be the first year in which the world adds more solar power capacity than wind. The service predicted that 36.7 gigawatts of new solar power capacity would be added in 2013, up 20 percent from 2012, compared to 35.5 gigawatts of new wind power. The service credited the speed-up to new incentives in Japan and China, combined with a dramatic reduction in the cost of solar panels.

Wind installations still contribute more than twice as much power as solar, representing 5 percent of global power supply compared to solar's 2 percent, but new installations are slowing as Chinese and American incentives lapse and windmills face greater competition from newly cheap solar panels. Bloomberg predicts the coming years will see the technologies even out, respectively contributing 17 percent and 16 percent of global power supply by 2030.