Ballpark Estimate: $15,000 to $55,000
A cool breeze on a hot summer day always feels great, but when that breeze is also running your dishwasher, computer, and TV set, it’ll feel even more refreshing. More and more people these days are harnessing the wind’s energy and using it to generate electricity for their homes. In fact, the American Wind Energy Association (AWEA) says that in 2007, wind power installations increased by 45% in the United States, and in 2008, we should, for the first time, see over 1 percent of the nation’s electricity generated by the wind. That doesn’t sound like much but it translates into 5,244 megawatts of energy and $9 billion in sales and installation costs.
While the U.S. still lags far behind countries like Germany and Spain in wind energy use, interest is definitely growing as we search for better ways to conserve natural resources, reduce global warming emissions, reduce pollution, and free ourselves from the oil and fossil fuel companies.
Electricity Use in the U.S.A.
- If you leave a 40 watt light bulb burning for 24 hours, it will use up approximately 1 kilowatt hour (kWh) of electricity.
- One kilowatt hour from the utility grid generates 1.5 pounds of carbon dioxide – almost half a pound of carbon emissions.
- It takes 1 gallon of oil to produce 40 kilowatt hours of electricity.
- The average household uses over 10,000 kilowatt hours of electricity each year.
- In 2007, the average cost for electricity from the utility grid was about 10.7¢ per kilowatt hour.
What About Wind Power?
- In 2007, average cost per kilowatt hour of electricity generated by residential wind energy systems was between 10–11¢ per kilowatt hour.
- In 2007, average cost per kilowatt hour of electricity generated by utility-scale wind turbines was 4–7¢ per kilowatt hour.
- One 10 kilowatt wind turbine system, operating at a site where the average wind speed is at least 12 mph, can generate around 10,000 kilowatts per year.
How Does Wind Power Work?
A modern residential wind turbine is complex. Here are some of its most basic components:
The tower supports the wind turbine and gets it up above trees, buildings, and other obstacles. Residential wind turbine towers are usually between 30 and 100 feet tall. In most cases, increased tower height results in better performance of the wind turbine system. The wind turbine attaches to the top of the tower on a bearing that allows it to rotate freely towards the direction of the wind.
The turbine is the spinning part of the wind turbine system that generates the electricity. The turbine consists of:
- Blades – Most wind turbines have three blades, usually made of a plastic fiberglass composite.
- Rotor – The blades are connected to a double rotor assembly. The blade rotor spins when the blades catch the wind. The magnet rotor spins around a magnetic alternator, creating a magnetic field and producing an electrical charge.
- Controller – The controller converts the raw electricity to direct current (DC) power and sends it either to a battery or an inverter.
Batteries are optional. Most modern residential wind turbines are tied directly to the utility grid and don’t use batteries, but if you have a stand-alone wind turbine system, or you want back-up in case of power outages, batteries are needed for storage.
The inverter converts DC power from the batteries to active current (AC), used in your home and on the utility grid.
Your utility company will install a bi-directional meter that tracks the amount of energy your wind turbine system produces and the amount of energy your household consumes.
The swept area is the circular area covered by the turbine’s spinning blades. If your rotor assembly has a diameter of 12 feet, the swept area is 113 square feet.
Before You Buy
- Figure out what wind resources are available at your site. The U.S. Department of Energy publishes wind resource data, and you can hire a wind consultant to visit your site, take measurements, and give you a prediction of what to expect as far as wind energy production.
- Check with your electricity provider to obtain approval and agreements prior to installation.
- Check with your local governments, aviation board, and neighborhood associations, which sometimes object to residential wind turbines because of appearance, noise, or worries about property values. You may be asked for letters of support from your neighbors.
- Contact the National Audubon Society or local resources to determine if your site is in a bird migratory path. It’s unlikely that a single residential wind turbine, out of the migratory path, will cause trouble for birds, but California’s Altamont Pass Wind Resource Area is located in a migratory route and kills thousands of birds each year.
- Gather your energy bills for the past year or two and figure out exactly how much electricity your household uses annually.
- Currently, there is no certification process in the United States that covers turbine manufacture or performance. Consequently, residential wind turbines do not have to meet national or international standards of safety or reliability. Research your company thoroughly, and invest in the best equipment, design, and installation you can realistically afford.
- Be aware of your wind turbine system’s country of origin. Particularly if you buy from an individual owner or small company that imports systems, be sure that expert advice, maintenance, service, and parts will be readily available for years to come.
Are There Financial Incentives?
While solar energy is reaping the benefits of increased federal, state, regional, and manufacturing incentives, wind energy is still struggling for support.
Production Tax Credit (PTC)
Recently extended by Congress through 2008, this federal incentive for wind power credits each kilowatt hour produced over the first 10 years of the wind turbine system’s life, but is not particularly useful for homeowners.
If you’re connected to the grid, your meter keeps track of how much power your system generates and how much you use. When your wind turbine system produces more electricity than you can use, that power is diverted to the public utility grid, and your meter spins backwards, as you are credited, at retail rates, for that power. As of December 2007, net metering is available in over 42 states and the District of Columbia.
There are hopes for a future federal tax credit equal to 30% of the wind turbine cost up to $4,000, but this is still in the wait-and-see stages.
In late 2007, Congress passed a bill to help states provide grants and low-interest loans for residential wind turbine systems. Some states offer sizable rebates through regional energy commissions.
As of 2007, there were 12 established residential wind turbine manufacturers in the United States.
What Size System Do I Need?
With a solar energy system, you can start small and add solar panels as space, needs, or your funds increase. But with wind turbine systems, homeowners generally install one tower and turbine and that’s it. Installing a wind turbine system one year and a second system a few years later is economically, physically, and often socially impractical.
The most cost-effective approach is to determine your household’s energy needs, your site’s wind resources, and the practicality of installing a wind turbine system. Then talk to professionals to decide what size system to buy and how high to mount it.
How Much Does a Residential Wind Turbine Cost?
For residential use, you will want a wind turbine system with an output of 2 – 10 kilowatts per hour, depending on the size and energy efficiency of your home, and your family’s needs. Your bottom line costs will include: turbine, tower, inverter, wiring, foundation, shipping, installation, zoning and permit fees, and more.
Urban and Suburban Wind Turbine System (turbine only, tower and installation not included) – $6,500 to $15,500
The Helix Wind Savonious is a revolutionary design that can be used in urban and suburban settings because of its very small footprint and ease of installation. Sizes range from 2–5 kilowatt systems. The turbine can be mounted on a 15–35 foot tower, or can be roof-mounted two feet above roof line. The scoop-shaped rotor is only 6 x 4 feet, has a quieter action, and is more bird-friendly, neighbor-friendly, and zoning commission-friendly than traditional systems.
Suburban Wind Turbine System (self-installed) – $15,000
The Skystream 3.7 is a new wind turbine system designed specifically for suburban homeowners looking for affordable solutions with a small “footprint,” that they can install themselves. Towers range in the 30- to 40-foot range, and rotor diameter is 12 feet. This system operates at wind speeds as low as 9mph and can generate between 1.8 and 2.4 kilowatts – enough to satisfy 50% to 100% of the needs of an average, energy efficient home. The system pays for itself in 5 to 15 years.
Suburban and Rural Wind Turbine System (tower, wiring, fees and installation included before rebates and other incentives) – $22,000 to $55,000
Larger systems range from 4 to 8 kilowatts with towers up to 100 feet tall. These will generally produce enough electricity to completely satisfy the needs of most American homes with average energy efficiency.
A 10 Kilowatt System – $80,000 to $125,000
This is a very substantial wind turbine system requiring a 90- to 120-foot tower, large-size turbine, special zoning and town permits to erect the structure, and hefty shipping and installation costs. Once up and running, this system will produce enough energy to completely satisfy the needs of a very large house, or possibly a business or large school. This price includes professional installation, before rebates and incentives.
How Much Will You Save?
Of course, it all depends. How much you save depends on the energy efficiency of your home and your local electricity rates. However, depending on your wind turbine system size, wind quality, permit and energy costs, and turbine performance, payback periods for small wind systems range from 6 to 15 years. Larger systems (10 kilowatt) can take 15 to 30 years to make up your initial costs.