A device used to protect the user of any electrical system or appliance from shock.

A condition that can occur in a solar collector if the working fluid does not circulate when sun is shining on the collector.

The abrupt and large increase in electrical conductivity exhibited by some metals as the temperature approaches absolute zero.

An energy system in which the fuel production equipment is in close proximity, or connected to, the fuel using equipment.

The generation of electricity or shaft power by an energy conversion system and the concurrent use of rejected thermal energy from the conversion system as an auxiliary energy source.

The process of degrading organic material (biomass) by microorganisms in aerobic conditions.

The trapping of light by refraction and reflection at critical angles inside a semiconductor device so that it cannot escape the device and must be eventually absorbed by the semiconductor.

The physical measure of the subjective sensation of brightness; measured in lumens.

A solar photovoltaic product that generally consists of groups of PV cells electrically connected together to produce a specified power output under standard test conditions, mounted on a substrate, sealed with an encapsulant, and covered with a protectiv ...

An electrical installation containing power conversion (and sometimes generation) equipment, such as transformers, compensators, and circuit breakers.

The low effective temperature of the sky on a clear night.

A room that faces south (in the northern hemisphere), or a small structure attached to the south side of a house.

Energy derived from resources that are regenerative or for all practical purposes can not be depleted. Types of renewable energy resources include moving water (hydro, tidal and wave power), thermal gradients in ocean water, biomass, geothermal energy, so ...

A value that describes the ability of a material to conduct heat. The number of Btu that flow through 1 square foot of material, in one hour. It is the reciprocal of the R-Value (U-Value = 1/R-Value).

A type of heating appliance that extracts so much of the available heat content from a combusted fuel that the moisture in the combustion gases condenses before it leaves the furnace. Also this furnace circulates a liquid to cool the furnace's heat exchan ...

The production of hydrogen using a photoelectrochemical cell.

An investment in a power plant or demand side management measures or programs, that become uneconomical due to increased competition in the electric power market. For example, an electric power plant may produce power that is more costly than what the mar ...

A type of home mortgage that takes into account the energy savings of a home that has cost-effective energy saving improvements that will reduce energy costs thereby allowing the homeowner to more income to the mortgage payment. A borrower can qualify for ...

The two times of the year when the sun crosses the equator and night and day are of equal length; usually occurs on March 21st (spring equinox) and September 23 (fall equinox).

A heat exchanger that transfers heat contained in a liquid heat transfer fluid to another liquid.