In a solar energy system, refers to all components other than the collector. In terms of costs, it includes design costs, land, site preparation, system installation, support structures, power conditioning, operation and maintenance costs, indirect storag ...

An outdoor temperature, usually 20 to 45 degrees Fahrenheit, at which a heatpump's output equals the heating demand. Below the balance point, supplementary heat is needed.

A means of reducing the volume of a material by compaction into a bale.

A device used to control the voltage in a fluorescent lamp.

The measure of the efficiency of fluorescent lamp ballasts. It is the relative light output divided by the power input.

The ratio of light output of a fluorescent lamp operated on a ballast to the light output of a lamp operated on a standard or reference ballast.

In a semiconductor, the energy difference between the highest valence band and the lowest conduction band.

The amount of energy (in electron volts) required to free an outer shell electron from its orbit about the nucleus to a free state, and thus promote it from the valence to the conduction level.

42 U.S. gallons (306 pounds of oil, or 5.78 million Btu).

The amount of heat given off by a person at rest in a comfortable environment; approximately 50 Btu per hour (Btu/h).

Power generated by a utility unit that operates at a very high capacity factor.

A type of radiant heating system where the radiator is located along an exterior wall where the wall meets the floor.

The power output of a power plant that can be continuously produced.

The minimum demand experienced by a power plant.

A power plant that is normally operated to generate a base load, and that usually operates at a constant load; examples include coal fired and nuclear fueled power plants.

The conditioned or unconditioned space below the main living area or primary floor of a building.

A process for carrying out a reaction in which the reactants are fed in discrete and successive charges.

A flexible roll or strip of insulating material in widths suited to standard spacings of building structural members (studs and joists). They are made from glass or rock wool fibers. Blankets are continuous rolls. Batts are pre-cut to four or eight foot l ...

An energy storage device composed of one or more electrolyte cells.

Energy storage using electrochemical batteries. The three main applications for battery energy storage systems include spinning reserve at generating stations, load leveling at substations, and peak shaving on the customer side of the meter.