It’s ugly. It costs too much. The ROI doesn’t pencil out. What people used to say about residential solar-electric power generation is now being applied to another renewable power option, wind.
Then again, offering new, better-built homes that generate “free” energy and amortizing its up-front costs (minus tax credits and other rebates) into a 30-year mortgage may be just the ticket to push your homes into the sales column.
Like solar, a small wind turbine designed for a single residence is most effective (and only practical) when added to a high-performance home. Assuming other optimum conditions—namely, average annual wind speeds over 12 mph—a 10 kW turbine can offset up to 80 percent of grid-supplied electricity.
Recent support among policymakers (tax credits), utilities (rebates and net-metering), and local zoning authorities (height variances) has helped push wind power closer to practical reality. Despite the economy and a $20,000 installed cost, the residential wind sector grew 78 percent in 2008 and another 15 percent (about 10,000 installs) last year to crest the 100,000-unit threshold.
Even with its limitations, the potential market for small-system turbines is about 13 million installations, says Ron Stimmel, small-systems manager at the American Wind Energy Association. “It’s the next step beyond making a home energy efficient,” he says. A wind resource map from the DOE shows a swath of optimum conditions from the Dakotas to North Texas, while a table produced by the National Climate Data Center shows average annual wind speeds for hundreds of cities.
A more realistic opportunity, says Stimmel, may be in systems that serve a community instead of individual homes, such as La Casa Verde in San Francisco, where a trio of turbines generates 40 percent of the project’s electricity.