Wind turbines use generators powered by the wind to create electricity. Although designs vary by manufacturer, most small wind turbines generate varying three-phase alternating voltage (AC) electricity known as wild AC at the turbine. The wild AC is then converted to direct current (DC) electricity, and then modified to alternating current (AC) using one or more inverters. The inverter output is 120 or 240-volt electricity that can be used in your home or business.
Evergreen Energy installed one of the first large residential wind turbines in Connecticut in December 2009. Evergreen Energy installs small wind turbines from five to one hundred kilowatts in capacity.
Wind Turbines must be installed where the wind is. In most cases, that means above the ground clutter (e.g., houses, garages, trees, etc.). As a general rule that means at least 30 feet above the treetops for a 300-foot radius. Most turbines work best on a tower that is at least 80 feet tall; however, you should always install a taller tower if possible. Most small wind turbines are installed on towers that are 100 to 140 feet tall. In addition to the height consideration, you need a good size land parcel and towns can often have setback requirements. As a general rule, you need a 2-acre lot for a turbine. Setback requirements are often based on the tower height plus some safety margin. For example, a turbine with a 20-foot rotor diameter on a 100-foot tower may have a setback distance of 130 feet (the tower height plus the blade length plus 20 feet).
Incentives for small wind turbines include a full 30% federal tax credit through the American Recovery and Reinvestment Act for turbines installed after December 31, 2008. A tax credit reduces your tax liability by the credit amount so it actually reduces the cost of the project by that amount.