An approximate unit of heat produced by a resting person, equal to about 18.5 Btu per square foot per hour.

A high-intensity discharge lamp type that uses mercury and several halide additives as light-producing elements. These lights have the best Color Rendition Index (CRI) of the High-Intensity Discharge lamps. They can be used for commercial interior lightin ...

A colorless, odorless, tasteless gas composed of one molecule of Carbon and four of hydrogen, which is highly flammable. It is the main constituent of "natural gas" that is formed naturally by methanogenic, anaerobic bacteria or can be manufactured, and w ...

A clear, colorless, very mobile liquid that is flammable and poisonous; used as a fuel and fuel additive, and to produce chemicals.

A unit of mass equal to 1,000 kilograms or 2,204.6 pounds.

The local climate of specific place or habitat, as influenced by landscape features.

A small groove scribed into the surface of a solar photovoltaic cell which is filled with metal for contacts.

One millionth of a meter (10-6 m).

A common utility monetary measure equal to one-thousandth of a dollar or a tenth of a cent.

A current carrier, either an electron or a hole, that is in the minority in a specific layer of a semiconductor material; the diffusion of minority carriers under the action of the cell junction voltage is the current in a photovoltaic device.

The average time a minority carrier exists before recombination.

A valve operated by a thermostat that can be installed in solar water heating systems to mix cold water with water from the collector loop to maintain a safe water temperature.

A method used to estimate building heating loads by assuming that heat loss and gain is proportional to the equivalent heat-loss coefficient for the building envelope.

The smallest self-contained, environmentally protected structure housing interconnected photovoltaic cells and providing a single dc electrical output; also called a panel.

The water content of a substance (a solid fuel) as measured under specified conditions being the: Dry Basis, which equals the weight of the wet sample minus the weight of a (bone) dry sample divided by the weight of the dry sample times 100 (to get percen ...

The process of controlling indoor moisture levels and condensation.

The planting, cultivation, and harvesting of a single species of crop in a specified area.

Fabricated as a single structure.

A machine supplied with external energy that is converted into force and/or motion.

The number of revolutions that the motor turns in a given time period (i.e. revolutions per minute, rpm).