If you have equipment that generates wind energy, you are eligible for a tax credit to reduce the amount of tax you owe. Wind energy tax credits fit into a larger category called renewable energy tax credits.
The government offers these tax credits to encourage investment in renewable energy sources, which reduce dependence on fossil fuels, including foreign oil.
Credits are more powerful than tax deductions because they directly reduce your tax burden dollar-for-dollar, rather than just reduce the amount of income subject to tax. To claim them, you do your taxes as normal and then apply the credits.
There may also be credits available in your state. To see what your state has to offer, visit this web site: http://www.dsireusa.org/