The two times of the year when the sun is apparently farthest north and south of the earth's equator; usually occurring on or around June 21 (summer solstice in northern hemisphere, winter solstice for southern hemisphere) and December 21 (winter solstice ...

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 amount of solar energy that passes through a glazing material, expressed as a percentage.

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

The period marked by successive crossing of the earth's meridian by the sun; the hour angle of the sun at a point of observance (apparent time) is corrected to true (solar) time by taking into account the variation in the earth's orbit and rate of rotatio ...

A deposition process whereby heat is used to break molecules into elemental sources that are then spray deposited on a substrate.

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

see Solar Spectrum above.

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

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.)

Usually refers to ethanol to 160 to 200 proof.

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

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

A steady-state fermentation process.

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

The total distribution of electromagnetic radiation emanating from the sun. The different regions of the solar spectrum are described by their wavelength range. The visible region extends from about 390 to 780 nanometers (a nanometer is one billionth of o ...

A commonly used analysis for reporting fuel properties; may be on a dry (moisture free) basis, as "fired", or on an ash and moisture free basis. Fractions usually reported include: volatile matter, fixed carbon, moisture, ash, and heating value (higher he ...

A unit for the quantity of electricity transported in 1 second by a current of 1 ampere.

Thermal energy that is used in agricultural and industrial operations.

A law to protect consumers and investors. It placed geographic restrictions on mergers and limitations on diversification into non-utility lines of business and takeovers of electric and gas utilities, and also established regulated monopoly markets or se ...