A measure of the electrical resistance of a material equal to the resistance of a circuit in which the potential difference of 1 volt produces a current of 1 ampere.

A layer of semiconductor material, such as copper indium diselenide or gallium arsenide, a few microns or less in thickness, used to make solar photovoltaic cells.

A turbine that is driven by high velocity jets of water or steam from a nozzle directed to vanes or buckets attached to a wheel. (A pelton wheel is an impulse hydroturbine).

A raw material that can be converted to one or more products.

In a wind energy conversion system, to pitch the turbine blades so as to reduce their lift capacity as a method of shutting down the turbine during high wind speeds.

The amount of work accomplished by electrical power, usually measured in kilowatt-hours (kWh). One kWh is 1,000 Watts and is equal to 3,413 Btu.2.The energy of moving electrons.

Fuel gas with a heating value of between 200 and 300 Btu per cubic foot.

The wind speed with 50 percent probability of occurring.

A battery-powered electrically driven vehicle.

The decomposition of organic material to alcohol, methane, etc., by organisms, such as yeast or bacteria, usually in the absence of oxygen.

A unit or measure of electricity supply or consumption of 1,000 Watts over the period of one hour; equivalent to 3,412 Btu.

A device that tracks the movement of the sun; used to orient solar concentrating systems.

The quantity of heat necessary to raise the temperature of a specific mass of a substance by one degree.

A registered trademark name for houses built with tires, aluminum cans, and earth.

A construction element that inhibits termites from entering building foundations and walls.

The sum of all the costs both recurring and nonrecurring, related to a product, structure, system, or service during its life span or specified time period.

The arrangement, proportion, and design of windows in a building.

An idealized process in which a working fluid (water, air, ammonia, etc) successively changes its state (from a liquid to a gas and back to a liquid) for the purpose of producing useful work or energy, or transferring energy.

A device for converting continuous circular motion into reciprocating rectilinear motion.

The discomfort or interference with visual perception when viewing a bright object against a dark background.