Rate of wind movement in distance per unit time.

A graph that indicates the distribution of wind speeds as a function of the cumulative number of hours that the wind speed exceeds a given wind speed in a year.

A curve that indicates the number of hours per year that specific wind speeds occur.

A profile of how the wind speed changes with height above the surface of the ground or water.

A term used for a wind energy conversion device that produces electricity; typically having one, two, or three blades.

The amount of power a wind turbine can produce at its rated wind speed, e.g., 100 kW at 20 mph. The rated wind speed generally corresponds to the point at which the conversion efficiency is near its maximum. Because of the variability of the wind, the amo ...

An instrument used to indicate wind direction.

A component of the wind (often using Cartesian coordinates. i.e. X and Y wind vectors). Also, an arrow representing wind velocity, drawn to point in the direction of the wind and with a length proportional to wind speed.

The wind speed and direction in an undisturbed flow.

A vector term which includes both wind speed and wind direction.

An anchor engine used for heaving in the chain cable and anchor.

A machine designed to drop and hoist the anchor. It has one or more cable lifters mounted on a horizontal shaft, each being fitted with a brake. The cable lifters are capable of being declutched from the prime mover. One or two warping ends may also be fi ...

A WECS that is used to grind grain, and that typically has a high-solidity rotor; commonly used to refer to all types of WECS.

A rotation anemometer in which the axis of rotation is horizontal. The instrument has either flat vanes (as in the air meter) or helicoidal vanes (as in the propeller anemometer). The relation between wind speed and angular rotation is almost linear.

A generic term for a glazed opening that allows daylight to enter into a building and can be opened for ventilation.

A graph representing the relationship between the power available from the wind and the wind speed. The power from the wind increases proportionally with the cube of the wind speed.

The change in the power available in the wind due to changes in the windspeed or velocity profile; the windpower profile is proportional to the cube of the wind speed profile.

The wind speed and direction at various levels in the atmosphere above the level reached by surface weather observations.

The measurement and computation of wind speeds and directions at various levels above the surface of the earth. Methods include pilot balloon observations, rabals, rawin or rawinsonde observations, radar tracking, or acoustic sounding.

A graphical aid used in the reduction of data from a winds aloft observation.