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 ...

A device for removing heat from a gas or liquid stream for air conditioning/cooling.

The two times of the year when the sun crosses the equator and night and day are of equal length; usually occurs on March 21st (spring equinox) and September 23 (fall equinox).

An optical device for concentrating light that is made of concentric rings that are faced at different angles so that light falling on any ring is focused to the same point.

The energy lost from the movement of a fluid in a conduit (pipe) due to the disturbances created by the contact of the moving fluid with the surfaces of the conduit, or the additional pressure that a pump must provide to overcome the resistance to fluid f ...

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 ...

One horsepower provided over one hour; equal to 0.745 kilowatt-hour or 2,545 Btu.

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

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

The trapping of light by refraction and reflection at critical angles inside a semiconductor device so that it cannot escape the device and must be eventually absorbed by the semiconductor.

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.

This is another name for an induction motor. The motors consist of a rotor inside a stator. The rotor has laminated, thin flat steel discs, stacked with channels along the length. If the casting composed of bars and attached end rings were viewed without ...

The ratio of solar radiation captured and transfered to the collector (heat transfer) fluid.

An estimate of power demand at some future period.

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

The force per unit area acting on the surface of a solid boundary parallel to the flow.

The process of sending or moving electricity from one point to another; usually defines that part of an electric utility's electric power lines from the power plant buss to the last transformer before the customer's connection.

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

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 ...