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

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 ...

An inverter that operates independent of or is not connected to an electric transmission and distribution network.

A term used to describe heat energy lost from a water heater tank.

A large power plant that generates power for distribution to multiple customers.

The production of hydrogen using a photoelectrochemical cell.

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

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

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

A type of solar thermal collector that has tubes (pipes) that the heat transfer fluid flows through that are connected to a flat absorber plate.

Turbines in which the axis of the rotor's rotation is parallel to the wind stream and the ground.

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).

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

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

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

A solar collector that uses reflective surfaces to concentrate sunlight onto a small area, where it is absorbed and converted to heat or, in the case of solar photovoltaic (PV) devices, into electricity. Concentrators can increase the power flux of sunlig ...

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

A free and mobile conduction electron or hole in a semiconductor.

The duct(s) of a forced air heating/cooling system through which heated or cooled air is supplied to rooms by the action of the fan of the central heating or cooling unit.

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