Generation from wind turbines in the United States increased 27% in 2011 compared to 2010, continuing a trend of rapid growth. During the past five years capacity additions of wind turbines were the main driver of the growth in wind power output. As the amount of wind generation increases, electric power system operators have faced challenges with integrating increasing amounts of this intermittent generation source into their systems.
Federal production tax credits and grants for electricity from certain renewable sources as well as State-level renewable portfolio standards have encouraged both capacity additions and increased generation from wind and other renewable sources.
Although increasing, electricity from wind contributed to less than 3% of total generation in 2011. Wind energy is the largest source of non-hydroelectric renewable electricity in the United States, contributing 61% of the nearly 200 terawatthours of non-hydroelectric renewable generation in 2011. EIA recently released preliminary data through December 2011 on generation, fuel consumption, and other statistics for the electric power industry in the Electric Power Monthly and Electricity Monthly Update.