A mathematical representation of the frequency or ratio that specific wind speeds occur within a specified time interval.

States that energy cannot be created or destroyed, but only changed from one form to another. First Law efficiency measures the fraction of energy supplied to a device or process that it delivers in its output. Also called the law of conservation of energ ...

The arithmetic wind speed over a specified time period and height above the ground (the majority of U.S. National Weather Service anemometers are at 20 feet (6.1 meters).

Alternating current is carried by conductors and a ground to residential, commercial, or industrial consumers. The waveform of the phase power appears as a single continuous sine wave at the system frequency whose amplitude is the rated voltage of the pow ...

The amount of solar radiation striking a surface per unit of time and area.

A heating system where heat is supplied (radiated) into a room by means of heated surfaces, such as electric resistance elements, hot water (hydronic) radiators, etc.

The process by which materials expel or release gasses.

The process of the absorption of heat from one location and its transfer to another for rejection or recuperation.

The ratio of the radiant energy (heat) leaving (being emitted by) a surface to that of a black body at the same temperature and with the same area; expressed as a number between 0 and 1.

The total diffuse and direct insolation on a horizontal surface, averaged over a specified period of time.

A unit of pressure for a fluid, commonly used in water pumping and hydropower to express height a pump must lift water, or the distance water falls. Total head accounts for friction head losses, etc.

The amount of heat introduced to a space from all heat producing sources, such as building occupants, lights, appliances, and from the environment, mainly solar energy.

The process of managing the consumption of energy, generally to optimize available and planned generation resources.

A wall to prevent the spread of fire; usually made of non-combustible material.

A company or individual that is not directly regulated as a utility. These entities produce power for their own use and/or sell it to regulated utilities.

A wood-burning appliance for space and/or water heating and/or cooking.

The amount of useful energy produced by a system less the amount of energy required to produce the fuel.

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.

In alternating current, the current goes from zero potential or voltage to a maximum in one direction, back to zero, and then to a maximum potential or voltage in the other direction. The number of complete cycles per second determines the current frequen ...

A WECS designed to produce electricity.