Wind energy is a form of renewable energy usually using specially designed wind turbines to generate electricity. They are an updated form of the windmills of old often used to pump water as in Holland.
Modern wind turbines are designed to adapt to wind conditions and to synchronize power generated to the 60 hz frequency of the grid they feed.
Wind turbines now are often collected into wind farms in areas where winds are favorable. An issue has been that these regions are often not on the traditional electric grid. Hence, new high tension power lines are needed to bring the electricity to market. T. Boone Pickens is on record asking the federal government to ease the permitting process.
Warren Buffett and Boone Pickens are both well known for their investment in midwestern wind farms. The dust bowl of the '30s should indicate considerable wind potential. Farmers see wind farms as a source of additional income. John Deere was a participant financing wind investments. In August, 2010, the company announced the sale of its wind energy business to Exelon. Offshore projects are under consideration off Cape Cod and New Jersey.
Traditionally, General Electric was the leading supplier of wind turbines in the US. A Wall Street Journal article of September 19, 2011, reports that GE is now second largest globally with 11% market share. Vestas Wind Systems of Denmark is the leader. Sinovel Wind Group Co. of China is a player, having been named in a recent theft of technology lawsuit. American Superconductor Corp of Devens, MA is a supplier of turbine designs and electronics, often through licensing deals in China, Korea, Taiwan, India, Turkey and the Czech Republic. Otter Tail was once mentioned as major player. Indian producers were reportedly coming on strong. Suzlon Energy of India is a manufacturer. Trinity Industries is a manufacturer of structural wind towers.
The industry has been bothered by complaints of noise, and of injury to birds and wildlife. Modern wind turbines are huge--up to 380 ft in diameter. Tall towers are needed to reach favorable winds. They must be sturdy to resist storm damage. Delamination of large fiberglass blades has been a problem.
Rare earth metals are considered essential for the manufacture of wind turbines. Availability of these metals has been a concern. In recent times China has been able to dominate production and price competitors out of the market.
For a summary of wind energy equipment suppliers see the following: 
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