From 2007 to 2011, average battery costs for battery-powered electric vehicles fell by about 14 percent a year. For the leading electric vehicle makers, Tesla and Nissan, costs fell by 8 percent a year.According to Bloomberg View, the price has kept falling at about the same rate in 2012-2014. Annual declines of 8 to 14% per year add up to revolutionary cost reductions in a hurry. This matters because as the price of large batteries falls, it becomes much easier to power things with an intermittent source like solar or wind power. You can already power your house with solar cells plus a big battery, but the battery is expensive and not terribly reliable. If the price of batteries falls by 75 or even 50%, and mass production makes them more reliable, big battery systems will multiply all across the globe.
Instead of thinking of solar and batteries as two independent things, we should think of them as one single unified technology package. Solar-plus-batteries is set to begin a dramatic transformation of human civilization. The transformation has already begun, but will really pick up steam during the next decade.Within a decade all your eco-crazy and tea party neighbors will be powering their homes with solar cells and batteries, and they will laugh at your foolish reliance on big business and big government when the power goes out.