Solar power is becoming more competitive with conventional sources of energy. Due to economies of scale and, in part, China's overproduction, the price of solar panels has fallen dramatically. And owing to technological advancement, they are more efficient. Some industry analysts expect solar energy could provide as much as 18% of energy needs in parts of Europe. This first Great Graphic comes from an article by Pilita Clark of the Financial Times.
Germany is one of the leading countries in the use of renewable energy. It is home to about a third of the photovoltaic capacity, which accounted for an estimated 5% of the country's energy needs in 2012, up from 3% in 2011. Overall, renewable energy accounted for a little more than a fifth of Germany's energy needs last year, while natural gas share slipped to 11% from 14%. 
Globally, the electricity produced by solar energy has grown 4-fold over the past decade form 2.8 gigawatts to 102 gigawatts.Industry expert project a doubling by 2016. The price per watt has fallen precipitously from $70 a watt (in 2012 dollars), when first introduced in the 1970s, to 80 cents a watt now. Prices have fallen nearly 80% in the past five years alone.
This second Great Graphic is part of a larger chart by Thomson Reuters. It shows the wind energy capacity globally as of the end of last year. The EU's wind energy capacity was a little larger than China, India and Canada's combined. China's wind energy capacity outstrips the US. Another way of looking at it, the EU, China and the US account for 7/8 of the world's wind energy capacity. 
This last Great Graphic shows the the growth of land-based wind power in the US (purple line) and the sharp drop in the cost of generating a kilowatt hour of electricity. It comes from the Climate Group's website thecleanrevolution.org.
Drawing on data from the Department of Energy, Climate Group reports that US-land based wind energy capacity has grown three-fold between 2008 and 2012 to 60 gigawatts. US solar capacity grew 10-fold over the same period.
Solar energy was Europe's fastest growing source of electricity in 2012 (for the third year running), while wind power overtook solar power in 2012 as the America's fastest growing new source of electricity. By 2030, the DOE estimates that as much as a fifth of US electricity demand could be met by wind power.