How Wind Technology Works Wind is a form of energy that can be “harvested” by wind turbines to generate electricity. Somewhat like old fashioned windmills, today’s wind machines use blades to collect the wind’s energy. The wind flows over the airfoil shaped blades causing lift, like the effect on airplane wings, causing them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity.
That electricity is tranferred to a nearby "substation" where the current is adjusted to ensure it can be routed over large "transmission lines". These lines are of various sizes (measured typically in kilovolts) and, with their towers, can be seen dotting the landscape. The lines terminate in other cities and even other states as he independent wind power producer is free to negotiate with a variety of large power utilities and co-ops who offer "green energy" to their customers.
Wind turbines come in a variety of sizes, depending upon the use of the electricity. A large, utility-scale turbine may have blades over 40 meters long. This makes the diameter of the rotor span nearly the length of a football field. This giant turbine might be mounted on a tower 80 meters tall, produce approximately 1.8 megawatts of power (1,800 kilowatts), supply enough electricity for 600 homes and cost over a million and a half dollars. Wind turbines designed to supply part of the electricity used by a home or business are much smaller and less costly. A residential- or farm-sized turbine may have a rotor up to 15 meters (50 feet) in diameter and be mounted on a metal lattice tower up to 35 meters (120 ft) tall. These turbines may cost as little as a few thousand dollars for a very small unit up to $80,000. Very small turbines may be designed to charge batteries to supply electricity to homes that are not connected to the utility system or used by rural farmers to power their small needs.
