Electromagnetic radiation in the wavelength range of 4 to 400 nanometers.

The maximum heat output (in Btu per hour) released by a burner with a stable flame and satisfactory combustion.

Describes the reliability of power plants. It refers to the number of hours that a power plant is available to produce power divided by the total hours in a set time period, usually a year.

The total cost of production divided by the total quantity produced.

A type of hydroturbine in which the entire generator is mounted inside the water passageway as an integral unit with the turbine. These installations can offer significant reductions in the size of the powerhouse.

A device that cuts off the flow of hot or cold air to or from a room as controlled by a thermostat.

A condition that results from an imbalance between the number of protons and the number of electrons in a substance.

Energy systems supply individual, or small-groups, of energy loads.

Heat stored above room temperature (in a solar heating system).

The maximum load that a motor is capable of supplying.

As defined by the Energy Security Act (PL 96-294) of 1980, "any organic matter which is available on a renewable basis, including agricultural crops and agricultural wastes and residues, wood and wood wastes and residues, animal wastes, municipal wastes, ...

A term used for the transparent or translucent material in a window. This material (i.e. glass, plastic films, coated glass) is used for admitting solar energy and light through windows.

Discharging a battery to 20 percent or less of its full charge capacity.

The process or technologies for producing energy by harnessing the temperature differences (thermal gradients) between ocean surface waters and that of ocean depths. Warm surface water is pumped through an evaporator containing a working fluid in a closed ...

The purpose for which useful energy or work is consumed.

A measure of the heating requirements of a building expressed in Btu per degree-day.

A popular term for "non-conventional" transportation fuels derived from natural gas (propane, compressed natural gas, methanol, etc.) or biomass materials (ethanol, methanol).

A slender threadlike spike of pure crystalline material, such as silicon.

The negative pole or electrode of an electrolytic cell, vacuum tube, etc., where electrons enter (current leaves) the system; the opposite of an anode.

A program of the U.S. Department of Energy (DOE) that implements energy legislation and presidential directives. FEMP provides project financing, technical guidance and assistance, coordination and reporting, and new initiatives for the federal government ...