Wind power - clean and efficient
Wind power is growing worldwide as a major source of renewable energy. To meet the demand for alternative energy sources, large numbers of wind power generators are being deployed on wind farms both at land and sea. Home wind power is also growing rapidly as residential wind power generators are becoming increasingly efficient and practical. Do it yourself wind turbines are sprouting up across the country with some very innovative designs.
In the US, wind power generation has doubled in the last two years to more than 20 gigawatts, and recently passed Germany as the world leader in wind energy generation. Even with these strides, wind power currently provides less than 2% of the US electricity supply. However, government forecasts optimistically call for wind power to provide 20% of the nation’s electricity by 2030.
History of wind power
Wind has been used for thousands of years as a source of power. Sailboats are one of the purest, and simplest examples of the wind as power source. Before the advent of electricity, windmills were used primarily to pump water and grind, or "mill" grain. The power of the wind was used to turn the blades of a rotor, which was connected to grinding stones or a pumping mechanism. Wind power was thus converted into mechanical energy and was a more efficient way to perform everyday tasks.
The popularity of using the energy in the wind has always fluctuated with the price of fossil fuels. When fuel prices fell after World War II, interest in wind turbines waned. But when the price of oil skyrocketed in the 1970s, so did worldwide interest in wind turbine generators.
The wind turbine technology research and development that followed the oil embargoes of the 1970s refined old ideas and introduced new ways of converting wind energy into useful power. Many of these approaches have been demonstrated in "wind farms" or wind power plants — groups of turbines that feed electricity into the utility grid — in the United States and Europe.
Today, the lessons learned from more than a decade of operating wind power plants, along with continuing research and development, have made wind-generated electricity very close in cost to the power from conventional utility generation in some locations. Wind energy is the world's fastest-growing energy source and will power industry, businesses and homes with clean, renewable electricity for many years to come.
How does wind power work?
The terms wind energy or wind power describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity. Simply stated, a wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Advantages of Wind Power
Wind power offers many advantages, which explains why it's the fastest-growing energy source in the world. A road map for energy independence based on strong national investment in wind power has been the cornerstone of T. Boone Pickens "Pickens Plan".
Wind energy is fueled by the wind, so it's a clean fuel source. Wind energy doesn't pollute the air like power plants that rely on combustion of fossil fuels, such as coal or natural gas. Wind turbines don't produce atmospheric emissions that cause acid rain or greenhouse gasses.
Wind energy is a domestic source of energy, produced in the United States. The nation's wind supply is abundant.
Wind energy relies on the renewable power of the wind, which can't be used up.
Wind energy is one of the lowest-priced renewable energy technologies available today, costing between 4 and 6 cents per kilowatt-hour, depending upon the wind resource and project financing of the particular project.
Wind turbines can be built on farms or ranches, thus benefiting the economy in rural areas, where most of the best wind sites are found. Farmers and ranchers can continue to work the land because the wind turbines use only a fraction of the land. Wind power plant owners make rent payments to the farmer or rancher for the use of the land.
Disadvantages of Wind Power
Wind power must compete with conventional generation sources on a cost basis. Depending on how energetic a wind site is, the wind farm may or may not be cost competitive. Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators.
The major challenge to using wind as a source of power is that the wind is intermittent and it does not always blow when electricity is needed. Wind energy cannot be stored (unless batteries are used); and not all winds can be harnessed to meet the timing of electricity demands.
Good wind sites are often located in remote locations, far from cities where the electricity is needed.
Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation.
Although wind power plants have relatively little impact on the environment compared to other conventional power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and sometimes birds have been killed by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants.
20% Wind Energy by 2030
In 2008, the U.S. Department of Energy published a report that examines the feasibility of using wind energy to generate 20% of the nation's electricity demand by 2030. The report, "20% Wind Energy by 2030: Increasing Wind Energy's Contribution to U.S. Electricity Supply," includes contributions from DOE and its national laboratories, the wind industry, electric utilities, and other groups. The report examines the costs, major impacts, and challenges associated with producing 20% wind energy or 300 GW of wind generating capacity by 2030.
The report's conclusions include:
- Reaching 20% wind energy will require enhanced transmission infrastructure, streamlined siting and permitting regimes, improved reliability and operability of wind systems, and increased U.S. wind manufacturing capacity.
- Achieving 20% wind energy will require the number of turbine installations to increase from approximately 2000 per year in 2006 to almost 7000 per year in 2017.
- Integrating 20% wind energy into the grid can be done reliably for less than 0.5 cents per kWh.
- Achieving 20 percent wind energy is not limited by the availability of raw materials.
- Addressing transmission challenges such as siting and cost allocation of new transmission lines to access the Nation's best wind resources will be required to achieve 20% wind energy.