U.S. wind power installations rose 31% in 2011, but the industry faces an uncertain future if Congress does not extend tax credits set to expire by year's end, the American Wind and Energy Association said in its annual report released Thursday.

In 2011, the wind industry installed 3,464 wind turbines for a total of 6,816 megawatts in the United States, up from 5,215 megawatts installed in 2010.

Despite the positive trend, the looming expiration of the industry's Production Tax Credit could result in job losses and impact orders for U.S. wind industry manufacturers, the association reported.

The federal Production Tax Credit is an incentive awarded based on kilowatt-hours produced by a wind farm once it is built.

The last time the Production Tax Credit expired in 2003 wind power installations dropped between 73% and 93%, the association reported.

Critics say the incentives unfairly subsidize one form of energy over others.

Manufacturing Impact

In 2011, the U.S. wind industry employed 75,000 people, including 30,000 in manufacturing. These companies include manufacturers that produce wind-specific components and raw materials such as composites and steel.

General Electric Co. (IW 500/4) business unit GE Energy led wind turbine manufacturers in the United States with a capacity market share of 29.4% and 36.2% of the turbine market share.

Danish wind turbine manufacturers Vestas Wind Systems AS (IW 1000/418) moved from sixth place in 2010 to second in installations, bumping Siemens AG (IW 1000/26) to third.

Regional Leaders

States with the highest levels of wind generation came primarily from the Midwest and Great Plains states, including South Dakota, Iowa, North Dakota, Minnesota and Wyoming.

South Dakota led all states for wind generation with 22.3% of the state's electricity derived from wind power, the association reported.

Iowa earned the No. 1 ranking for wind industry employment in 2011 with more than 6,000 people employed by the industry in the Hawkeye State.

Kansas topped all states for wind projects under construction in 2012 with an additional 1,189 megawatts planned this year.

See also:

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