The picture below is a 2.4kW wind turbine installed in the backyard of a Mission District home in SF. It generates on average 400 kWh of power a month. A standard 3 bedroom house in SF typically will not use more than 400 kWh of electricity in summer. The installed cost of this system roughly costs $28,000 before incentives. With Federal and State incentives, you may only need to pay 50% of the cost. Depending on where your house is located, the same turbine will have slightly different performance.