What is Wind Energy?
Wind power plants are turbines which use the energy in the motion of the wind to make mechanical energy, which is then converted to electrical energy.
The components of a utility-scale "wind farm" include wind turbines, an underground power transmission system, control and maintenance facilities, and a substation that connects the farm with the utility power grid. Utility-scale wind turbines are classified by size as follows: small (less than 50 kilowatts [kW]); intermediate (50 to 500 kW); and large (above 500 kW). Small and intermediate turbines make up the bulk of the older installed turbine base, but new turbines installed in the late 1990s are generally 600 kW and larger.
Utility-scale wind farms are generally located in areas with average annual wind speeds of at least 13 miles per hour. Wind power is more available during certain seasons because climatic conditions affect wind speed. In California, wind speeds are highest in the hot summer months, and approximately three-fourths of all annual wind power output is produced during the spring and summer.
Another application of wind is in distributed use systems, which provide on-site power in either stand-alone or grid-connected configurations. Most such systems range in size from one to 25 kW. Distributed wind systems are applicable to industry, water districts, rural residences, agricultural use, and a wide variety of isolated power uses located in good wind resource areas.
Wind power for utility-scale applications is considered to be commercially available under most conditions. The technology is considered to be mature, and there are several system suppliers. The federal government encourages electricity production from wind farms with a 1.5-cent per kilowatt-hour tax credit. California also offers incentives through the Existing Renewables Program ($70.2 million for Tier 2, wind) and the New Renewables Program (nearly 1,000 megawatts of new, installed capacity is being added under this program).
Wind power for distributed applications is considered to be commercially available under limited conditions. Distributed wind systems can be a cost-effective option in remote locations where a utility connection would not be economically feasible. The California Energy Commission supports grid-connected small wind systems or 10 kW or less through the Emerging Renewable Rebate Program.
While the power produced by many of California's older wind turbines is not cost-competitive with other forms of electricity generation, some of the newest wind turbine designs may be able to match or beat the power prices from many coal and nuclear plants.
Sources: California Energy Commission, California Independent System Operator, Crossborder Energy