Energy terms starting with A

236 terms

AADT See Average Annual Daily Traffic
Abiotic Absence of living organisms.
Absolute Humidity The ratio of the mass of water vapor to the volume occupied by a mixture of water vapor and dry air.
Absorbent A material that extracts one or more substances from a fluid (gas or liquid) medium on contact, and which changes physically and/or chemically in the…
Absorber The component of a solar thermal collector that absorbs solar radiation and converts it to heat, or, as in a solar photovoltaic device, the material that…
Absorption (ub-SORP-shun) The process of taking nutrients from the digestive system into the blood so they can be used in the body.
Absorption Chiller A type of air cooling device that uses absorption cooling to cool interior spaces.
Absorption Coefficient In reference to a solar energy conversion devices, the degree to which a substance will absorb solar energy.
Absorption Cooling A process in which cooling of an interior space is accomplished by the evaporation of a volatile fluid, which is then absorbed in a strong solution, then…
Absorption Refrigeration A system in which a secondary fluid absorbs the refrigerant, releasing heat, then releases the refrigerant and reabsorbs the heat.
absorptivity In a solar thermal system, the ratio of solar energy striking the absorber that is absorbed by the absorber to that of solar energy striking a black body…
AC Armor Class or Defense.
Acceleration (peak horizontal) A measure of earthquake acceleration (i.e., shaking) on the ground surface expressed in g, the acceleration due to the Earth's gravity.
Accent lighting Draws attention to special features or enhances the aesthetic qualities of an indoor or outdoor environment.
Access roads Gravel or dirt roads (rarely paved) that provide overland access to transmission line and pipeline rights-of-way (ROWs) and facilities for construction…
Accessory Dwelling Unit (ADU) A self-contained housing unit incorporated within a single-family dwelling (not within accessory structures, except with a Special Permit) that is clearly…
Accumulating shear A feller-buncher shearhead that is capable of accumulating and holding 2 or more cut stems.
Accumulator A component of a heat pump that stores liquid and keeps it from flooding the compressor.
acetic acid An acid with the structure of C2H4O2. Acetyl groups are bound through an ester linkage to hemicellulose chains, especially xylans, in wood and other…
ACID A solution that has an excess of hydrogen ions (H+).
Acid deposition A comprehensive term for the various ways acidic compounds precipitate from the atmosphere and deposit onto surfaces.
acid detergent fiber (ADF) Organic matter that is not solubilized after one hour of refluxing in an acid detergent of cetyltrimethylammonium bromide in 1N sulfuric acid.
Acid hydrolysis A chemical process in which acid is used to convert cellulose or starch to sugar.
acid insoluble lignin Lignin is mostly insoluble in mineral acids, and therefore can be analyzed gravimetrically after hydrolyzing the cellulose and hemicellulose fractions of…
Acid Rain A term used to describe precipitation that has become acidic (low pH) due to the emission of sulfur oxides from fossil fuel burning power plants.
acid soluble lignin A small fraction of the lignin in a biomass sample is solubilized during the hydrolysis process of the acid insoluble lignin method.
Activated sludge process A biological wastewater treatment process in which a mixture of waste water and activated sludge is agitated and aerated.
Active Cooling The use of mechanical heat pipes or pumps to transport heat by circulating heat transfer fluids.
Active Management Area (AMA) Active Management Areas were established in Arizona to provide long-term management and conservation of limited groundwater supplies.
Active Power The power (in Watts) used by a device to produce useful work. Also called input power.
Active Solar Heater A solar water or space-heating system that use pumps or fans to circulate the fluid (water or heat-transfer fluid like diluted antifreeze) from the solar…
Active traders Market participants who trade frequently, often many times a day, and therefore are attune to the ebbs and flows, the rumors, breaking news, activities of…
Active volcano A volcano that is erupting. Also, a volcano that is not presently erupting, but that has erupted within an historical time and is considered likely to…
Actual cubic feet per minute (ACFM) The actual cubic feet per minute of gas flowing in a process at the temperature and pressure of the process at that point.
Acute (uh-KYOOT) Symptoms or signs that begin and worsen quickly; not chronic.
Adaptive management A continuing process of action-based planning, monitoring, researching, evaluating, and adjusting with the objective of improving implementation and…
Adaptive Management Area (AMA) Landscape units designated for development and testing of technical and social approaches to achieving desired ecological, economic, and other social…
Adequate Public Facilities Adequate public facilities ordinances prevent new construction until municipal services, including water, sewer, roads, and schools, are available to…
Adequate Water Supply Program The Arizona Adequate Water Supply Program requires anyone who offers subdivided land outside of an Active Management Area for sale or lease to obtain a…
Adiabatic Without loss or gain of heat to a system. An adiabatic change is a change in volume and pressure of a parcel of gas without an exchange of heat between…
Adjustable Speed Drive An electronic device that controls the rotational speed of motor-driven equipment such as fans, pumps, and compressors.
Adobe A building material made from clay, straw, and water, formed into blocks, and dried; used traditionally in the southwestern U.S.
Adsorption The adhesion, in an extremely thin layer, of molecules (as in gases, solutions, or liquids) to the surface of solid bodies or liquids with which they are…
Advanced Technology Vehicles A vehicle that combines new engine, power, or drivetrain systems to significantly improve fuel economy.
Adverse environmental impacts Impacts that are determined to be harmful to the environment. See also Effects
Aeration basin A basin where oxygen is supplied by mechanical agitation or pneumatic means to enhance the breakdown of wastes held in suspension.
AERMOD A refined, steady-state plume model that incorporates air dispersion on the basis of a state-of-the-art planetary boundary layer turbulence structure and…
Aerobic In biochemistry, reactions that need oxygen to happen or happen when oxygen is present.
Aerobic Bacteria Microorganisms that require free oxygen, or air, to live, and that which contribute to the decomposition of organic material in soil or composting systems.
aerobic fermentation Fermentation processes that require the presence of oxygen.
AFederal Air Contaminant Discharge Permit (ACDP) In Oregon, the Department of Environmental Quality issues the ACDP.
Affected Environment For an environmental impact statement, a description of the existing environment covering information necessary to assess or understand the impacts.
Aftershocks Earthquakes that follow the largest shock of an earthquake sequence. They are smaller than the main shock and within one to two rupture lengths distance…
Aggregate 1. A clump or mass formed by gathering or collecting units. 2. A body of loosely associated cells, such as a friable callus or cell suspension. 3.
Agricultural Districts/Preservation Areas Areas designed to keep land in agriculture that are legally recognized. Landowners may voluntarily enroll in programs and may receive special benefits and…
Agricultural fires Fires ignited to meet specific management objectives on agricultural lands.
Agricultural Preservation Restriction Program (APR) A voluntary program which is intended to offer a non-development alternative to farmers and other owners or "prime" and "state important" agricultural…
agricultural residue Agricultural crop residues are the plant parts, primarily stalks and leaves, not removed from the fields with the primary food or fiber product.
Agricultural Zoning Agricultural zoning, including forestry zoning, restricts land uses to farming and livestock, other kinds of open-space activities and limited home…
Air The mixture of gases that surrounds the earth and forms its atmosphere, composed of, by volume, 21 percent oxygen, 78 percent nitrogen.
Air Change A measure of the rate at which the air in an interior space is replace by outside (or conditioned) air by ventilation and infiltration; usually measured…
Air Collector In solar heating systems, a type of solar collector in which air is heated in the collector.
Air Conditioner A device for conditioning air in an interior space. A Room Air Conditioner is a unit designed for installation in the wall or window of a room to deliver…
Air Conditioning The control of the quality, quantity, and temperature-humidity of the air in an interior space.
Air Diffuser An air distribution outlet, typically located in the ceiling, which mixes conditioned air with room air.
Air Infiltration Measurement A building energy auditing technique used to determine and/or locate air leaks in a building shell or envelope.
Air pollutant Any substance in the air which could, if in high enough concentration, harm humans, other animals, vegetation, or material.
Air Pollution The presence of contaminants in the air in concentrations that prevent the normal dispersive ability of the air, and that interfere with biological…
Air Pollution Control The use of devices to limit or prevent the release of pollution into the atmosphere.
Air quality Measure of the health-related and visual characteristics of the air to which the general public and the environment are exposed.
Air Quality Control Region (AQCR) An interstate or intrastate area designated by the U.S. Environmental Protection Agency for the attainment and maintenance of National Ambient Air Quality…
Air Quality Maintenance Area Specific populated area where air quality is a problem for one or more pollutants.
Air Quality Standards The prescribed level of pollutants allowed in outside or indoor air as established by legislation.
Air Register The component of a combustion device that regulates the amount of air entering the combustion chamber.
Air Retarder/Barrier A material or structural element that inhibits air flow into and out of a building's envelope or shell.
Air Space The area between the layers of glazing (panes) of a window.
Air-Source Heat Pump A type of heat pump that transfers heat from outdoor air to indoor air during the heating season, and works in reverse during the cooling season.
Air-to-Air Heat Pump see Air-Source Heat Pump.
Air-to-Water Heat Pump A type of heat pump that transfers heat in outdoor air to water for space or water heating.
Airlock Entry A building architectural element (vestibule) with two airtight doors that reduces the amount of air infiltration and exfiltration when the exterior most…
Airtight Drywall Approach (ADA) A building construction technique used to create a continuous air retarder that uses the drywall, gaskets, and caulking.
Albedo The ratio of light reflected by a surface to the light falling on it.
Albedo (effects) The fraction of solar radiation reflected by a surface or object, often expressed as a percentage.
alcohol (AL-kuh-hol) A chemical substance found in beer, wine, and liquor. Alcohol is also found in some medicines, mouthwashes, essential oils (scented liquid…
aldehyde (AL-deh-hide) A type of chemical substance made from alcohol. Aldehydes are found in essential oils (scented liquid taken from plants).
aldoses Occur when the carbonyl group of a monosaccharide is an aldehyde. (Source: Voet, D.; Voet, J. G. Biochemistry. New York: John Wiley, 1990.)
Algae Simple plant organism (typically a single cell) commonly found in water.
Aliquot (parts) The standard subdivisions of a section (usually 640 acres [2.6 km2]) of land, such as a half section, quarter section, or quarter-quarter section.
Alkali A soluble mineral salt.
alkali lignin Lignin obtained by acidification of an alkaline extract of wood.
Alkali sink A land basin in which water evaporation produces high salt concentrations that may, or may not, support salt marsh vegetation.
alkaline hydrolysis The use of solutions of sodium hydroxide (or other alkali) in the treatment of cellulosic material (wood) to break down cellulose to simple sugars.
All-American Canal The All-American Canal System, located in the southeastern corner of California, consists of the Imperial Diversion Dam and Desilting Works, the…
All-American Roads A National Scenic Byway is a road recognized by the U.S. Department of Transportation for its archeological, cultural, historic, natural, recreational…
Allotment An area of land where one or more livestock operators graze their livestock. Allotments generally consist of BLM lands but may also include other…
Alluvial Formed by the action of running water; of or related to river and stream deposits.
Alluvial fan A fan-shaped depositional landform consisting of alluvial deposits that formed where a flowing stream slows and spreads out (depositing its load)…
Alluvial flats Small flat areas or plains (with slopes of less than 5 or 10 feet per mile) built of fine sediments deposited during flooding events.
Alluvial plains Small flat areas or plains (with slopes of less than 5 or 10 feet per mile) built of fine sediments deposited during flooding events.
Alluvial valley An alluvium-filled basin, usually occurring between mountain ranges.