Electricity produced in wind turbines is transported to the consumer via a series of transmission and distribution networks. Each component of the network changes the voltage of the electrical power to optimize its transition to the next part of the network. Due to the structure of these networks it is currently not possible to buy wind energy alone.
Wind turbines capture the kinetic energy in wind and convert it into electrical power. Large blades on the turbine rotor are connected to an electrical generator via a shaft and a series of gears. Wind blowing past the blades causes the shaft to rotate. In the generator, the rotating shaft causes a set of magnets to turn about a coil of wire to create an electric current due to electromagnetic induction.
Turbine to Transmission Grid
Electricity from the wind turbine generator travels to a transmission substation where it is converted into extremely high voltage, between 155,000 and 765,000 volts, for long distance transmission on the transmission grid. This grid comprises a series of power lines that connect the power sources to demand centers. According to the Energy Information Association, the United States has three major transmission grids: the Eastern, Western and Texas interconnects.
Grid to Consumer
Power substations at the demand centers convert the high voltage power from the transmission grid to a lower voltage power, typically in the region of 10,000 volts. From here it moves into a smaller distribution grid to which consumers are connected to this grid via another transformer. Here the distribution voltage is converted to the desired consumer voltage.
Buying Wind Energy
All sources of electricity feed power into the same grid. It is therefore impossible to know exactly where the power you are buying comes from. Many utilities now offer the option of purchasing “green energy” at a higher rate. The increased tariff subsidizes the development of renewable energy sources like wind power. According to Wind Energy America, by choosing to buy renewable energy you are telling the utility that you are concerned about the environment and are willing to pay more to protect it.
About the Author
Michael Owen holds a PhD in mechanical engineering. His fields of expertise include fluid dynamics, heat transfer and computational fluid dynamics. His interests include renewable energy and sustainability.