U.S. wind energy installations exceed 10,000 MW as of August 2006.

According to the American Wind Energy Association:

The industry is gaining momentum as it grows. The first commercial wind farms were constructed in California in the early 1980s, and after reaching 1,000 MW in 1985, it took more than a decade for wind to reach the 2,000-MW mark, in 1999. Since then, however, installed capacity has grown fivefold (for a chart showing historical cumulative capacity, go to http://www.awea.org/faq/instcap.html ). Today, the industry is installing more wind power in a single year (3,000 MW expected in 2006) than the amount operating in the entire country in 2000 (2,500 MW).

http://www.awea.org/newsroom/releases/US_Wind_Energy_In...ilestone_081006.html