A unit of length named for A.J. Angstome, a Swedish spectoscopist, used in measuring electromagnetic radiation equal to 0.000,000,01 centimeters.

An alternative path. In a heating duct or pipe, an alternative path for the flow of the heat transfer fluid from one point to another, as determined by the opening or closing of control valves both in the primary line and the bypass line.

A method for making sheets of polycrystalline silicon (for solar photovlotaic devices) in which molten silicon is drawn upward by capillary action through a mold.

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

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

The amount of heat required to raise the temperature of a unit of water, at or near the temperature of maximum density, one degree Celsius (or Centigrade [C]); expressed as a "small calorie" (the amount of heat required to raise the temperature of 1 gram ...

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 ...

Solar radiation that is not scattered by dust or water droplets.

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.

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

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

The flow of air down a flue/chimney and into a house caused by low indoor air pressure that can occur when using several fans or fireplaces and/or if the house is very tight.

A colorless, odorless but poisonous combustible gas with the formula CO. Carbon monoxide is produced in the incomplete combustion of carbon and carbon compounds such as fossil fuels (i.e. coal, petroleum) and their products (e.g. liquefied petroleum gas, ...

The weight of oxygen taken up mainly as a result of the oxidation of the constituents of a sample of water by biological action; expressed as the number of parts per million of oxygen taken up by the sample from water originally saturated with air, usuall ...

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.

An ideal heat engine (conceived by Sadi Carnot) in which the sequence of operations forming the working cycle consists of isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression back to its initial state.

An architectural element for shading windows and wall surfaces placed on the exterior of a building; can be fixed or movable.

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

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

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.