An aluminum foil fabricated insulator with backings applied to provide a series of closed air spaces with highly reflective surfaces.

Solar collector thermal performance ratings based on collector efficiencies, usually expressed in Btu per hour for solar collectors under standard test or operating conditions for solar radiation intensity, inlet working fluid temperatures, and ambient te ...

A configuration of an electrical circuit in which the positive lead is connected to the negative lead of another energy producing, conducting, or consuming device. The voltages of each device are additive, whereas the current is not.

Power generated by a utility unit that operates at a very low capacity factor; generally used to meet short-lived and variable high demand periods.

A measure of the effective cooling capacity of a refrigerator, expressed in Btu per hour or in tons, where one (1) ton of capacity is equal to the heat required to melt 2,000 pounds of ice in 24 hours or 12,000 Btu per hour.

The total amount of electric energy loss in an electric system between the generation source and points of delivery.

The change in direction of a ray of light when it passes through one media to another with differing optical densities.

An electric current induced by radiant energy.

A component of a water heating system that opens at a designated temperature or pressure to prevent a possible tank, radiator, or delivery pipe rupture.

The thermal energy used in an industrial process.

For valves and fittings, implies that they are suitable for working pressures between 125 to 175 pounds per square inch.

A device or media that absorbs heat for storage for later use.

Any material that has a limited capacity for conducting an electric current. Certain semiconductors, including silicon, gallium arsenide, copper indium diselenide, and cadmium telluride, are uniquely suited to the photovoltaic conversion process.

A wheel that is designed to use the weight and/or force of moving water to turn it, primarily to operate machinery or grind grain.

A fluid used to absorb and transfer heat energy.

A way of joining photovoltaic cells or modules by connecting positive leads together and negative leads together; such a configuration increases the current, but not the voltage.

The amount of heat in a quantity of matter at a specific temperature and pressure.

The difference between the total cooling effect and the dehumidifying effect.

Space cooling achieved by shading, natural (unassisted, as opposed to forced) ventilation, conduction control, radiation, and evaporation; also called passive cooling.

A type of solar thermal collector in which a heat transfer fluid drips out of header pipe at the top of the collector, runs down the collector absorber and into a tray at the bottom where it drains to a storage tank.