Classifications of fires developed by the National Fire Protection Association.

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.

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

The amount that the voltage, current, and/or power output of a solar cell changes due to a change in the cell temperature.

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

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.

An electric current induced by radiant 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 thermal energy used in an industrial process.

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

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

The amount (percent) of light that is reflected by a surface relative to the amount that strikes it.

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

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 structure or media that absorbs heat.

A type of cooling system that uses a charging and discharging cycle with a thermal or latent heat storage subsystem.

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