The interior heat gain due to heat conduction, convection, and radiation from the exterior into the interior, and from occupants and appliances.

A type of impulse hydropower turbine where water passes through nozzles and strikes cups arranged on the periphery of a runner, or wheel, which causes the runner to rotate, producing mechanical energy. The runner is fixed on a shaft, and the rotational mo ...

A device used by energy auditors to pressurize a building to locate places of air leakage and energy loss.

A heat exchanger coil in which a fluid such as water is circulated and a fan blows air over the coil to distribute heat or cool air to the different rooms.

An electricity supplier rate structure in which the per unit price of electricity decreases as the amount of energy increases. Normally only available to very large consumers.

The ratio of the maximum demand on an electricity generating and distribution system to the total connected load on the system; usually expressed as a percentage.

The area between the layers of glazing (panes) of a window.

An enzyme complex, produced by fungi and bacteria, capable of decomposing cellulose into small fragments, primarily glucose.

The amount of heat energy that may be converted into useful energy from a fuel.

The conversion of the complex carbohydrates in organic material into energy.

A type of combustion heating appliance in which the combustion gases are vented to the outside, either with a fan (forced) or by natural convection.

The downward facing structural element that is directly opposite the floor.

The ratio of solar collector array area to actual land area.

A colorless, pungent, gas (NH3) that is extremely soluble in water, may be used as a refrigerant; a fixed nitrogen form suitable as fertilizer.

A pump for circulating the heat transfer fluid in a hydronic heating system.

A component of a hydropower plant; a pipe that delivers water to the turbine.

The amount of power a wind turbine can produce at its rated wind speed, e.g., 100 kW at 20 mph. The rated wind speed generally corresponds to the point at which the conversion efficiency is near its maximum. Because of the variability of the wind, the amo ...

Energy produced by the internal heat of the earth; geothermal heat sources include: hydrothermal convective systems; pressurized water reservoirs; hot dry rocks; manual gradients; and magma. Geothermal energy can be used directly for heating or to produce ...

These are separate and distinct organizational agencies within the U.S. DOE that market power at federal multipurpose water projects at lowest possible rates to consumers consistent with sound business principles. There are five PMA's: Alaska Power Admini ...

An apparatus for converting the energy available in the wind to mechanical energy that can be used to power machinery (grain mills, water pumps) and to operate an electrical generator.