The region between an n-layer and a p-layer in a single material, photovoltaic cell.

A chemical element, of atomic number 14, that is semi-metallic, and an excellent semiconductor material used in solar photovoltaic devices; commonly found in sand.

A coating applied to the surface of the glazing of a window to reduce heat transfer through the window.

A window located on the roof of a structure to provide interior building spaces with natural daylight, warmth, and ventilation.

That portion of an electricity supply system used to deliver electricity from points on the transmission system to consumers.

The interior area of a building, calculated in square feet or meters.

A solid that contains pores; normally, it refers to interconnected pores that can transmit the flow of fluids. (The term refers to the aquifer geology when discussing sites for CAES.)

A method of financial and economic analysis used to determine present and future values of investments or expenses.

A water and energy conserving device that limits the amount of water that a faucet or showerhead can deliver.

The amount of energy produced as a percentage of the amount of energy consumed.

A type of anaerobic digester that has a horizontal tank in which a constant volume of material is added and forces material in the tank to move through the tank and be digested.

The air that is supplied to the combustion chamber of a furnace.

The mean distance a free electron or hole moves before recombining with another hole or electron.

The power required to energize the magnetic field of a generator.

Usually refers to ethanol to 160 to 200 proof.

see Solar Spectrum above.

The quantity of heat that a cooling appliance is capable of removing from a room in one hour.

A plot of a wind energy conversion device's power output versus wind speed.

One layer of glass in a window frame. It has very little insulating value (R-1) and provides only a thin barrier to the outside and can account for considerable heat loss and gain.

The fossil fuels: coal, oil, and natural gas.