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.

The heat liberated by the combustion of a unit quantity of a fuel under specific conditions; measured in calories.

The angle between true south and the point on the horizon directly below the sun.

The fibrous material remaining after the extraction of juice from sugarcane; often burned by sugar mills as a source of energy.

The conversion of one form of energy into another by the action of plants or microorganisms. The conversion of biomass to ethanol, methanol, or methane.

Single-celled organisms, free-living or parasitic, that break down the wastes and bodies of dead organisms, making their components available for reuse by other organisms.

A generator producing alternating current by the rotation of its rotor, and which is powered by a primary mover.

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

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

An air pollution control device used to filter particulates from waste combustion gases; a chamber containing a bag filter.

Binary cycle systems can be used with liquids at temperatures less than 350 F (177 C). In these systems, the hot geothermal liquid vaporizes a secondary working fluid, which then drives a turbine.

An air infiltration measurement technique developed by the Brookhaven National Laboratory to measure changes over time (one week to five months) when determining a building's air infiltration rate. This test cannot locate exact points of infiltration, but ...

The non-combustible residue of a combusted substance composed primarily of alkali and metal oxides.

An instrument for measuring the force or velocity of wind; a wind guage.

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.

A cell produces electric energy by the galvanic oxidation of carbon; commonly used in household appliances.

The amount of money needed to purchase equipment, buildings, tools, and other manufactured goods that can be used in production.

A device for optimizing the anaerobic digestion of biomass and/or animal manure, and possibly to recover biogas for energy production. Digester types include batch, complete mix, continuous flow (horizontal or plug-flow, multiple-tank, and vertical tank), ...

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

The maximum load that a generating unit, power plant, or other electrical apparatus can carry under specified conditions for a given period of time, without exceeding its approved limits of temperature and stress.