Here’s what to know before you start.
An average American home uses roughly 10,000 kilowatt hours per year, depending on the size of the house and its location. You’d need a 10-kilowatt turbine to meet this kind of demand. Picture a windmill on a 100-foot tower, with blades 25 feet in diameter, and you start to appreciate that a little spinner strapped to the chimney won’t help keep the lights on.
So-called horizontal-axis turbines like this will cost between $25,000 and $30,000 — a figure that doesn’t include the tower, which is another $10,000 or so, plus labor, engineering, and the “balance of service” components such as cables and equipment that will safely tie you into your home’s service panel. All in all, you can easily drop $40,000 or more before you throw the big switch and start lowering your power bills by 50% or more.
But since wind’s payback is similarly measured in decades, you’ll want to do your homework before making such a significant up-front investment.
According to the American Wind Energy Association, wind will only make economic sense if you pay at least 10 cents per kilowatt hour for your electricity (check your last utility bill), and if you have at least 10 mile-per-hour average wind speeds. Zoom in on the U.S. Department of Energy Wind Resource Maps to find out if you’re in a suitable zone.
Fortunately, incentives make the price a little easier to bear. Chief among these is the federal renewable energy tax credit, which knocks 30% off the total installed cost of your system — slashing that $40,000 setup down to about $28,000. Beyond this, the Database of State Incentives for Renewables & Efficiency will unlock additional local and regional-government rebates and deals.
How to buy
There’s no central database of wind-turbine installers, but reputable firms can be found through dealers across the country. Like anything else involving the home, get an agreement in writing, check references, and ask to speak with others who have had similar systems installed.
Wind contractors will often offer an all-in-one price that includes a suitable turbine, tower, and other components. But comparison shopping can be challenging, because companies each select a different wind speed to rate the power output of their various models. “There is no way to easily compare turbines,” explains Larry Sherwood, a renewable-energy consultant and veteran of the U.S. solar industries.
Fortunately, that’s about to change. Sherwood is leading the Small Wind Certification Council, an organization that rates residential-scale windmills with standardized criteria for energy output, power, and noise.
The scoop on property value
No empirical evidence exists that wind towers or wind farms depress nearby property values, according to a 2009 study of 7,500 home sales within 10 miles of 24 wind installations, conducted by the Lawrence Berkeley Laboratory.
Typical concerns center around visible impacts of towers, but also noise. Turbines are far from silent, but depending on size, wind speed, and distance from nearby homes, the sound can be quite modest — like that of a washing machine humming on the spin cycle in your basement.
Share your concerns with your dealer, share your plans with your neighbors, and check with your local-government office about relevant permit requirements, as well as any existing land use-bylaws that may restrict the height of structures in your area. If the numbers add up for you, before long you can start spinning your way toward green, clean, and — eventually — dirt-cheap electricity.