Wind Power

aggregation Correct Answers Building several wind energy projects together so that they are treated as one larger project - to improve project economics. airfoil Correct Answers The cross section profile of the leeward side of a wind generator blade, designed to reduce drag and maximize lift. anemometer Correct Answers An instrument used to measure the velocity, or speed, of the wind. angle of attack Correct Answers The angle of relative airflow to a wind turbine's blade. armature Correct Answers The moving part of an alternator, generator, or motor. In many alternator designs, it carries the magnets and is attached to the blades and hub. Also called a rotor. availability factor Correct Answers The percentage of time that a wind turbine is able to operate and is not out of commission due to maintenance or repairs. average capacity (capacity factor) Correct Answers A measure of a wind turbine's productivity, calculated by the amount of power that a wind turbine produces over a set time period, divided by the amount of power that would have been produced if the turbine had operated at full capacity during that same time interval. average wind speed (velocity) Correct Answers The mean wind speed over a specified period of time. balancing Correct Answers Adjusting wind turbine blades' weight and weight distribution through two axes so that all blades are the same (eliminating vibration). Betz Coefficient Correct Answers 59.3%. This is the theoretical maximum efficiency at which a wind generator can operate, by slowing the wind down. If the wind generator slows the wind down too much, air piles up in front of the blades and is not used for extracting energy.