Wind Energy

How Wind Energy Works

The wind's kinetic energy can be harnessed by a wind turbine. The wind moves the turbine's blades, which transfer energy through a central hub to a generator. The generator converts this mechanical energy into electrical energy that is then delivered to the power grid.

Watch the video from The Science Channel on how it works: Deconstructed: How Wind Turbines Work >>

How Much Wind Energy Costs

According to the U.S. Department of Energy, the cost of wind energy has come down 85 percent in the last 20 years. As of 2010, top performing wind farms in areas with excellent wind resources had costs averaging about 7 cents per kilowatt-hour, making wind the most cost competitive source of non-hydroelectric renewable electricity. Major federal incentives for wind energy include a 30 percent production tax credit over the first ten years of operation.

Advantages of Wind Energy

There are more than 400 manufacturing facilities across the U.S. supplying some of the 8,000 components in a wind turbine

• In the right setting, wind power is one of the most environmentally benign sources of energy. It produces no polluting emissions of any kind, including those that cause global warming.
• Wind is free, inexhaustible and immune from fuel cost inflation.
• With careful siting and outreach to the local community, wind farms can be built in a fraction of the time it takes to construct coal or natural-gas power plants. A 50-megawatt wind farm can be completed in less than a year.
• In the right location, it takes only three to eight months for a wind energy farm to recoup the energy consumed by its building and installation -- one of the fastest "energy payback times" of any energy technology on the market.
• Although bird and bat safety are ongoing concerns, wind power does not contribute to the plethora of other environmental and public health costs caused by conventional fossil power production: acid rain in lakes, mercury in fish, particulate-matter respiratory illnesses, coal mine slag, nuclear waste fuel storage, and so on. These economic "externalities" from conventional fossil power production play out in other economic arenas, such as the $35 billion the government has paid over the last 30 years to cover the medical expenses of coal miners with black lung disease.
• Land leases for wind turbine systems help support farmers and ranchers. On a 250-acre farm, wind leases can generate about $14,000 of annual income with only about three acres taken out of production.
• The growing use of wind energy creates manufacturing and technical jobs, and significantly more jobs per dollar invested compared to non-renewables technology, according to the National Renewable Energy Laboratory.
• Wind power consumes no water during operation. This will be an increasingly important attribute as the water-energy nexus grows in importance and as water use becomes an increasingly important facet of defining sustainability.

What's around the Corner for Wind Energy

• New technologies are being developed for use in low-wind areas and offshore. Engineers are creating new blade designs, more efficient turbines and ocean mooring systems to produce economical wind energy in regions like the American heartland, stretching from central Texas to the Canadian border, and coastal areas from the Pacific Northwest to the Gulf of Mexico to Cape Cod. In addition, new technologies to drive our power grid will allow us to make better use of our existing grid so that we can minimize the impact of the transmission lines needed to deliver wind power to our cities.
• Costs will fall to compete with the cheapest traditional energy sources, such as natural gas, even in low-wind areas. The US Department of Energy aims to bring the cost of land-based wind energy down by 18% and the cost of offshore wind energy down by 63% by 2020.
• Wind power will expand to meet a much larger portion of U.S. energy demand. Experts at the National Renewable Energy Lab, a federal research lab, show that wind energy could supply 30 percent of the nation's electricity without any additional technologies and forthcoming studies will evaluate even higher fractions of wind on the grid.
• A national renewable energy standard could facilitate the development of affordable wind capacity by requiring utilities to include a certain percentage of clean energy resources in their electricity mix. This would provide the stable policy framework needed to sustainably grow wind into a significant fraction of our country’s energy supply. According to the Department of Energy, a renewable standard of 20 percent -- combined with efficiency programs -- could save consumers billions of dollars.
• Bird and bat safety must be fully addressed. The wind industry has made great strides in locating wind farms to prevent harming birds in flight; now attention is turning toward bats. Project developers must work with local bird and bat experts to avoid migration routes, and use new technologies to help flying creatures steer clear of turbines. Future innovations should make this even easier.
• Limitations to the capacity of the current power transmission system will be addressed in two ways: by making our electricity use more efficient, and by expanding the system. Both need to be done carefully to minimize impacts to natural values and landscapes as well as to avoid creating incentives for new coal-burning plants.