Energy terms starting with A

236 terms

Alluvian fan terrace A relict landform consisting of thick gravel, sand, and boulder deposits occurring along mountain fronts.
Alluvium Deposits of clay, silt, sand, gravel, or other particulate materials that have been deposited by a stream or other body of running water in a streambed…
Alpine Refers to high mountain areas above the timberline (where trees cease to inhabit extremely cold environments).
Alpine tundra Vegetation in montane habitats above the tree line. Vegetation consists of perennial forbs, grasses, sedges, and short woody shrubs.
Alquist-Priolo Earthquake Fault Zoning Act California seismic zoning act passed in 1972, in response to the 1971 San Fernando earthquake, to prevent building across the traces of active faults.
Alternating Current A type of electrical current, the direction of which is reversed at regular intervals or cycles; in the U.S.
Alternating current (AC) An electric current that reverses its direction at regularly recurring intervals.
Alternative Under the National Environmental Policy Act, a comprehensive management strategy.
Alternative fuel As defined in the Energy Policy Act of 1992 (EPACT): Methanol, denatured ethanol and other alcohols, separately or in blends of at least 10 percent by…
Alternative Fuel Vehicles A dedicated, flexible fuel, or dual-fuel vehicle designed to operate on at least one alternative fuel.
Alternative Fuels A popular term for "non-conventional" transportation fuels derived from natural gas (propane, compressed natural gas, methanol, etc.
Alternator A belt-driven device mounted on the front of the engine that recharges the battery while the engine is running.
Ambient Air The air external to a building or device.
Ambient air quality The condition of the air in the surrounding environment.
Ambient Air Quality Standards Regulations prescribing the levels of airborne pollutants that may not be exceeded during a specified time in a defined area.
Ambient lighting Provides general illumination indoors for daily activities, and outdoors for safety and security.
Ambient Temperature The temperature of a medium, such as gas or liquid, which comes into contact with or surrounds an apparatus or building element.
American Indian Religious Freedom Act of 1978 (AIRFA) Act requiring federal agencies to consult with tribal officials to ensure protection of religious cultural rights and practices.
American Society for Testing and Materials (ASTM) International A nonprofit organization that develops and delivers international standards. ASTM standards, test methods, specifications, and procedures are recognized…
Ammonia A colorless, pungent, gas (NH3) that is extremely soluble in water, may be used as a refrigerant; a fixed nitrogen form suitable as fertilizer.
Amorphous Semiconductor A non-crystalline semiconductor material that has no long-range order.
Amp-Hours A measure of the flow of current (in amperes) over one hour.
Ampere A unit of measure for an electrical current; the amount of current that flows in a circuit at an electromotive force of one Volt and at a resistance of…
Amphibian A cold-blooded, smooth-skinned vertebrate of the class Amphibia, such as a frog, toad, or salamander, that characteristically hatches as an aquatic larva…
amylase (AM-il-aze) An enzyme that helps the body digest starches.
Anadromous fish Fish that hatch in freshwater, migrate to the ocean to mature, then return to freshwater to spawn. An example is salmon.
Anaerobic An environment or condition in which molecular oxygen is not available for chemical, physical or biological processes.
Anaerobic Bacteria Microorganisms that live in oxygen deprived environments.
Anaerobic Digester A device for optimizing the anaerobic digestion of biomass and/or animal manure, and possibly to recover biogas for energy production.
anaerobic digestion Digestion of materials in the absence of oxygen. See: anaerobic respiration.
Anaerobic Lagoon A holding pond for livestock manure that is designed to anaerobically stabilize manure, and may be designed to capture biogas, with the use of an…
Ancillary services Those services necessary to support the transmission of electric power from seller to purchaser, given the obligations of control areas and transmitting…
Andesite Volcanic rock (or lava), characteristically medium dark in color and containing 54 to 62 percent silica and moderate amounts of iron and magnesium…
Anemometer An instrument for measuring the force or velocity of wind; a wind gauge.
Angle of Incidence In reference to solar energy systems, the angle at which direct sunlight strikes a surface; the angle between the direction of the sun and the…
Angle of Inclination In reference to solar energy systems, the angle that a solar collector is positioned above horizontal.
Angle of view The angle, both vertical and horizontal, between a viewer's line of sight and the landscape being viewed.
Angstrom Unit A unit of length named for A.J. Angstome, a Swedish spectroscopist, used in measuring electromagnetic radiation equal to 0.000,000,01 centimeters.
Anhydrous A compound that does not contain water. For example, fuel ethanol is referred to as "anhydrous ethanol" because most of the water has been removed.
Anhydrous Ethanol One hundred percent alcohol; neat ethanol.
Animal unit A unit of measure for rangeland livestock equivalent to one mature cow or five sheep or five goats, all over 6 months of age.
Animal Unit (AU) A measurement of herd size used in the dairy industry. One animal unit is equal to 1000 pounds of animals. For example, a 1,200-pound cow equals 1.2 AU.
Animal Unit Month (AUM) A standardized unit of measurement of the amount of forage required by an animal unit for one month.
Annexation A change in existing community boundaries resulting from the incorporation of additional land.
annual For FDM purposes, you are an annual filer if last year you filed an OGE Form 450 (or an OGE Form 450-A).
Annual Fuel Utilization Efficiency (AFUE) The measure of seasonal or annual efficiency of a residential heating furnace or boiler.
Annual Load Fraction That fraction of annual energy demand supplied by a solar system.
Annual Solar Savings The annual solar savings of a solar building is the energy savings attributable to a solar feature relative to the energy requirements of a non-solar…
Anode The positive pole or electrode of an electrolytic cell, vacuum tube, etc. (see also sacrificial anode).
Anthracite (coal) A hard, dense type of coal, that is hard to break, clean to handle, difficult to ignite, and that burns with an intense flame and with the virtual absence…
Anthropogenic Referring to alterations in the environment due to the presence or activities of humans.
Anthropogenic emissions Made by people or resulting from human activities. Usually used in the context of emissions that are produced as a result of human activities.
Anthropomorphic Described or thought of as having human form or human attributes.
Anthropomorphism Ascribing human qualities, characteristics, or behavior to inanimate objects, animals, or natural phenomena.
Antifreeze Solution A fluid, such as methanol or ethylene glycol, added to vehicle engine coolant, or used in solar heating system heat transfer fluids, to protect the…
Antireflection Coating A thin coating of a material applied to a photovoltaic cell surface that reduces the light reflection and increases light transmission.
Aperture An opening; in solar collectors, the area through which solar radiation is admitted and directed to the absorber.
Apparent Day A solar day; an interval between successive transits of the sun's center across an observer's meridian; the time thus measured is not equal to clock time.
Apparent Power (kVA) This is the voltage-ampere requirement of a device designed to convert electric energy to a non-electrical form.
Appliance A device for converting one form of energy or fuel into useful energy or work.
Appliance Energy Efficiency Ratings The ratings under which specified appliances convert energy sources into useful energy, as determined by procedures established by the U.S.
Appliance Standards Standards established by the U.S. Congress for energy consuming appliances in the National Appliance Energy Conservation Act (NAECA) of 1987, and as…
Application for Certification (AFC) Document required for submission to the California Energy Commission by proponents of power-generating facilities in California that have nameplate…
Appropriate Management Level (AML) The maximum number of animals (wild horses or burros) sustainable on a yearlong basis.
Appropriation Doctrine The system of water law primarily used in the western United States under which: 1.
Appropriations Refers to the process of divvying out water right allotments and beneficial uses within a water management district.
Aquaculture Farming of aquatic organisms, including fish, molluscs, crustaceans and aquatic plants.
Aquatic biota Collective term describing the organisms living in or depending on the aquatic environment.
Aquatic ecosystem The distinctive ecosystem dominated by water, aquatic plants, or aquatic animals.
Aquatic habitats Areas associated with water that provide food and cover and other elements critical to the completion of an organism's life cycle (e.g.
Aquatic opportunists Species that occupy both temporary and permanent waters.
aquatic plants The aquatic biomass resources, such as algae, giant kelp, other seaweed, and water hyacinth.
Aquifer A water-bearing geologic formation, sometimes confined between clay layers and sometimes on the surface.
Aquifer-basin-fill An aquifer located in a basin surrounded by mountains and composed of sediments and debris shed from those mountains.
Aquifer-carbonate rock An aquifer found in limestone and dolomite rocks. Carbonate aquifers typically produced hard water, that is, water containing relatively high levels of…
Aquifer-confined Soil or rock below the land surface that is saturated with water. There are layers of impermeable material both above and below it and it is under…
Aquifer-unconfined An aquifer whose upper water surface (water table) is at atmospheric pressure, and thus is able to rise and fall.
Aquifer-volcanic rock An aquifer in which the rock matrix is composed of volcanic rocks, (e.g., tuffs or basalt flows).
arabinan The polymer of arabinose with a repeating unit of C5H804. Can be hydrolyzed to arabinose. (Source: Voet, D.; Voet, J. G. Biochemistry.
arabinose A five-carbon sugar - C5H1005. A product of hydrolysis of arabinan found in the hemicellulose fraction of biomass.
Arable lands Refers to all lands generally under rotation whether it is under temporary crops, temporarily fallowed, or used as temporary meadows.
Arbitrage Arbitrage is the technique of simultaneously buying at a lower price in one market and selling at a higher price in another market to make a profit on the…
Archaeological site Any location where humans have altered the terrain or discarded artifacts during prehistoric or historic times.
Arctic tundra A treeless area between the icecap and the tree line of Arctic regions that has permanently frozen subsoil and supports low-growing vegetation such as…
Area of Potential Effect (APE) The geographic area or areas within which an undertaking (project, activity, program, or practice) may cause changes in the character or use of any…
Area sources (emissions) Any source of air pollution that is released over a relatively small area but which cannot be classified as a point source.
Areas of Critical Environmental Concern (ACEC) These areas are managed by the Bureau of Land Management and are defined by the Federal Land Policy and Management Act of 1976 as having significant…
Argon A colorless, odorless inert gas sometimes used in the spaces between the panes in energy efficient windows.
Arid A region that receives too little water to support agriculture without irrigation. Less than ten inches of rainfall a year is typically considered arid.
Arizona Water Banking Authority (AWBA) The AWBA was established in 1996 to increase utilization of the state's Colorado River entitlement and to develop long-term storage credits for the state.
aromatic (A-ruh-MA-tik) Having an odor, which often is pleasant or spicy.
Array (Solar) Any number of solar photovoltaic modules or solar thermal collectors or reflectors connected together to provide electrical or thermal energy.
Arrays See Photovoltaic (PV) array
Arroyo A Spanish word for brook that refers to a dry river, creek, or stream bed that temporarily or seasonally fills and flows after sufficient rain.
Artesian water (artesian pressure) Groundwater that is under pressure when tapped by a well and is able to rise above the level at which it is first encountered.
Artifact An object produced or shaped by human beings and of archaeological or historical interest.
Ash The non-combustible residue of a combusted substance composed primarily of alkali and metal oxides.
ASHRAE Abbreviation for the American Society of Heating, Refrigeration, and Air-Conditioning Engineers.
ASTM Abbreviation for the American Society for Testing and Materials, which is responsible for the issue of many standard methods used in the energy industry.
Asynchronous Generator A type of electric generator that produces alternating current that matches an existing power source.