A form of solar concentrating collector that does not track the sun.

The inner coil in a heat pump that, during the cooling mode, absorbs heat from the inside air and boils the liquid refrigerant to a vapor, which cools the house.

The central heating or cooling system contains a fan that gets its air supply through these ducts, which ideally should be installed in every room of the house. The air from a room will move towards the lower pressure of the return duct.

An estimate of power demand at some future period.

A masonry or metal stack that creates a draft to bring air to a fire and to carry the gaseous byproducts of combustion safely away.

A byproduct of low-temperature carbonization of a solid fuel.

The difference in electrical pressure (voltage) between any two points in an electrical system or between any point in an electrical system and the earth.

A unit of work done by the force of one dyne acting through a distance of one centimeter.

When the temperature of the hydrothermal liquids is over 350 F (177 C), flash-steam technology is generally employed. In these systems, most of the liquid is flashed to steam. The steam is separated from the remaining liquid and used to drive a turbine ge ...

An air conditioning system that comes in two to five pieces: one piece contains the compressor, condenser, and a fan; the others have an evaporator and a fan. The condenser, installed outside the house, connects to several evaporators, one in each room to ...

A container that holds rock used as the thermal mass to store solar energy in a solar heating system.

A device built into or installed above a combustion appliance to assure the escape of combustion byproducts, to prevent backdrafting of the appliance, or to neutralize the effects of the stack action of the chimney or vent on the operation of the applianc ...

The use of two or more different fuels (e.g. wood and coal) simultaneously in the same combustion chamber of a power plant.

The process by which a power plant, apparatus, or building is approved for operation based on observed or measured operation that meets design specifications.

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

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

A lamp that consists of a sealed arc tube inside a glass envelope, or outer jacket. The inner arc tube is filled with elements that emit light when ionized by electric current. A ballast is required to provide the proper starting voltage and to regulate c ...

A type of power inverter that produce a high quality (nearly sinusoidal) voltage, at minimum current harmonics.