Wind energy was the single largest source of new electricity generation capacity in the US during 2012, according to the American Wind Energy Association (AWEA). With 13,124 MW of new infrastructure, wind accounted for 42 percent of all new capacity, from renewable sources or otherwise, according to a press release put out by the organization.

The new growth takes America’s total installed wind capacity to 60,007 MW. This is sufficient, by AWEA’s estimation, to meet the electricity needs of 15 million homes. The US remains second to China, which had 62,000 MW of installed wind power at the close of 2011.

Though a bumper year, the rate of expansion is susceptible to the prevailing winds in Washington, DC. The fourth quarter of 2012 was the US wind industry’s strongest ever, seeing an additional 8,380 MW of capacity. But this has been attributed to the expectations that the Production Tax Credit (PTC) would expire on December 31, 2012. The PTC provides a tax credit of 2.2 cents per kilowatt-hour of electrical energy generated from a renewable source during its first decade in operation. As part of a last-minute budget deal, Congress extended the credit for another year, so the boom in new projects may continue.

With 1,826 MW, Texas installed more wind capacity than any other state in 2012; it was followed by California (1,656 MW), Kansas (1,440 MW), and Oklahoma (1,127 MW). Illinois, Iowa, Oregon, Michigan, Pennsylvania, and Colorado round out the top 10 states, each installing between approximately 500 and 1,000 MW.

Currently, all of America’s wind power is located on land. The National Renewable Energy Laboratory estimates there's the potential for almost 11 million megawatts of land-based wind power, capable of generating an estimated 38.5 billion megawatt-hours of electricity per year (about 10 times 2010 consumption).