Alternative energy technologies hold the key to curbing air pollution and global warming.

One of the oldest forms of energy harnessed by human beings, wind power today is one of the most promising alternatives to our society's current dependence on fossil fuels. Using advanced technologies, modern wind turbines are able to produce electricity for homes, businesses, and even utilities, with much less environmental cost than traditional fossil fuels. Wind power, already one of the most widely used alternative sources of energy today, will continue to prosper as new turbine designs currently under development reduce the costs of wind power and make wind turbines economically viable in more and more places.

Wind turbines are moved by the wind and convert this kinetic energy directly into electricity by spinning a generator. They use air foils or blades like the wing of an airplane to turn a central hub, which is connected through a series of gears to an electrical generator. The generator technology is identical to that employed by traditional fossil fuel generating plants. Wind turbines range from small residential systems to large utility systems; wind power systems are modular and can be scaled easily to any application

Currently, wind power is used extensively in four major types of applications:

• Remote Power -- Small wind turbine systems are often the most inexpensive source of power for remote sites. The turbines for this system are very simple and can operate unattended for long periods at harsh sites. Common applications include telecommunications, rural residences, and water pumping. Remote power systems using small American-made wind turbines have been installed in more than 70 countries around the world.
  
  
• Grid Connected -- This application of wind turbines is widely used for producing electric power on-site at homes, farms, and businesses which are already served by a utility grid. Because the average wind turbine generates electricity only 25 to 30 percent of the time, it may be important in areas where winds are seasonal or where storage systems are not cost-effective to be connected to the electric utility grid.
  
  
• Utilities -- Wind turbine systems are most promising as sources of centralized electric power. In the hills of Southern California, for example, thousands of turbines are installed in wind power plants, known as "wind farms."
  
  
• Hybrid Systems -- Remote wind power systems often incorporate additional generating systems such as diesel generators and solar arrays. These "hybrid" systems provide improved reliability of power supply and operational flexibility. When the power from the wind turbine is not sufficient to operate the load, the alternate power source comes on-line. The alternate source is used far less frequently in a hybrid system than if the wind system were not present.
  

While wind power may be one of the most environmentally benign sources of power, wind energy developers and environmentalists alike are concerned that bird deaths from collisions with wind turbines could pose a major obstacle to widespread deployment of the technology. In light of the problem, biologists are trying to discover which factors precipitate these accidents so that engineers can design turbines which raptors and other birds will be better able to avoid. While the overall impact may be slight, the fact that there is an impact at all shows that indeed there are costs to each and every energy option.

Despite some minor bumps in the road, wind energy has received high praise overall from energy and environmental experts, and offers utilities pollution-free electricity that is nearly cost-competitive with today's conventional sources. Major utilities that implement modern wind harnessing technologies into their energy production strategies stand to gain significant economic advantages while offsetting emissions of carbon dioxide and other harmful pollutants. Wind power is just another example of how some of humankind's earliest forms of energy provide a key link to a non-polluting, economically-viable future.

THE HISTORY OF WIND POWER

Wind power has perhaps the longest history of any of today's mainstream or alternative energy sources. More than 5,000 years ago, the Egyptians used the wind to sail ships on the Nile. Later, people built the first turbines to grind grain.

These machines looked like paddle wheels and were used in Persia as early as 200 B.C. By the 14th century, the Dutch had taken the lead in improving the design of windmills. They invented propeller type blades and used wind power to drain the marshes and lakes of the Rhone River delta.

In America, early European settlers used windmills to grind wheat and corn, to pump water, and to cut wood at sawmills. By the early twentieth century, small windmills were used for pumping water and electric power generation in Europe, the United States, Africa, and elsewhere. In addition to thousands of small wind electric generators, a few larger systems were built in North America and Europe.

In the 1970s, increases in the price of oil and other fossil fuels helped wind power return as an economically viable, alternative source of energy. Governments all over the world, especially in North America and Europe, instituted research and development programs. These efforts led to the development of modern wind turbines, which have dramatically reduced the cost of generating electricity from wind power.