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Glossary



Access
Acid mine drainage
Acid rain
Acquisition (foreign crude oil)
Acquisition (minerals)
Acquisition costs, mineral rights
Active power
Active solar
Actual peak reduction
Afforestation
AGA
Agglomerating character
Aggregator
Alternating current (AC)
American Indian Coal Lease
AMI
Amorphous silicon
Ampere
Amp-Hours
AMR
Anaerobic decomposition
Anaerobic lagoon
Angle of Incidence
ANSI
Anthracite
Anthropogenic
Antireflection Coating
API
API gravity
Apparent consumption, (coal)
Apparent consumption, natural gas (international)
Apparent power
Appliance Energy Efficiency Ratings
Aromatics
Array
Asbestos
Ash
ASTM
Auger mine
Auxiliary generator
Average daily production
Average mine price
Average Open Market Sales Price (coal)
Average Recovery Percentage (coal)
Average revenue per kilowatthour
Aviation gasoline (finished)
Backup generator
Backup power
Barrel
Barrels per stream day
Base gas
Access
Acid mine drainage
Acid rain
Acquisition (foreign crude oil)
Acquisition (minerals)
Acquisition costs, mineral rights
Active power
Active solar
Actual peak reduction
Afforestation
AGA
Agglomerating character
Aggregator
Alternating current (AC)
American Indian Coal Lease
AMI
Amorphous silicon
Ampere
Amp-Hours
AMR
Anaerobic decomposition
Anaerobic lagoon
Angle of Incidence
ANSI
Anthracite
Anthropogenic
Antireflection Coating
API
API gravity
Apparent consumption, (coal)
Apparent consumption, natural gas (international)
Apparent power
Appliance Energy Efficiency Ratings
Aromatics
Array
Asbestos
Ash
ASTM
Auger mine
Auxiliary generator
Average daily production
Average mine price
Average Open Market Sales Price (coal)
Average Recovery Percentage (coal)
Average revenue per kilowatthour
Aviation gasoline (finished)
Backup generator
Backup power
Barrel

Access

The customer's legal right as stipulated in his or her contract to utilize energy systems as a method of transferring energy to a home or business. (Source: Choose Energy )

Acid mine drainage

This refers to water pollution that results when sulfur-bearing minerals associated with coal are exposed to air and water and form sulfuric acid and ferrous sulfate. The ferrous sulfate can further react to form ferric hydroxide, or yellow boy, a yellow-orange iron precipitate found in streams and rivers polluted by acid mine drainage. (Source: EIA)

Acid rain

Also called acid precipitation or acid deposition, acid rain is precipitation containing harmful amounts of nitric and sulfuric acids formed primarily by sulfur dioxide and nitrogen oxides released into the atmosphere when fossil fuels are burned. It can be wet precipitation (rain, snow, or fog) or dry precipitation (absorbed gaseous and particulate matter, aerosol particles or dust). Acid rain has a pH below 5.6. Normal rain has a pH of about 5.6, which is slightly acidic. The term pH is a measure of acidity or alkalinity and ranges from 0 to 14. A pH measurement of 7 is regarded as neutral. Measurements below 7 indicate increased acidity, while those above indicate increased alkalinity. (Source: EIA)

Acquisition (foreign crude oil)

All transfers of ownership of foreign crude oil to a firm, irrespective of the terms of that transfer. Acquisitions thus include all purchases and exchange receipts as well as any and all foreign crude acquired under reciprocal buy-sell agreements or acquired as a result of a buy-back or other preferential agreement with a host government. (Source: EIA)

Acquisition (minerals)

The procurement of the legal right to explore for and produce discovered minerals, if any, within a specific area; that legal right may be obtained by mineral lease, concession, or purchase of land and mineral rights or of mineral rights alone. (Source: EIA)

Acquisition costs, mineral rights

Direct and indirect costs incurred to acquire legal rights to extract natural resources. Direct costs include costs incurred to obtain options to lease or purchase mineral rights and costs incurred for the actual leasing (e.g., lease bonuses) or purchasing of the rights. Indirect costs include such costs as brokers' commissions and expenses; abstract and recording fees; filing and patenting fees; and costs for legal examination of title and documents. (Source: EIA)

Active power

The component of electric power that performs work, typically measured in kilowatts (kW) or megawatts(MW). Also known as "real power." The terms "active" or "real" are used to modify the base term "power" to differentiate it from Reactive Power. See Power, Reactive Power, Apparent Power (Source: EIA)

Active solar

As an energy source, energy from the sun collected and stored using mechanical pumps or fans to circulate heat-laden fluids or air between solar collectors and a building. (Source: EIA)

Actual peak reduction

The actual reduction in annual peak load (measured in kilowatts) achieved by customers that participate in a utility demand-side management (DSM) program. It reflects the changes in the demand for electricity resulting from a utility DSM program that is in effect at the same time the utility experiences its annual peak load, as opposed to the installed peak load reduction capability (i.e., potential peak reduction). It should account for the regular cycling of energy efficient units during the period of annual peak load. (Source: EIA)

Afforestation

Planting of new forests on lands that have not been recently forested. (Source: EIA)

AGA

American Gas Association (Source: EIA)

Agglomerating character

Agglomeration describes the caking properties of coal. Agglomerating character is determined by examination and testing of the residue when a small powdered sample is heated to 950 degrees Centigrade under specific conditions. If the sample is "agglomerating," the residue will be coherent, show swelling or cell structure, and be capable of supporting a 500-gram weight without pulverizing. (Source: EIA)

Aggregator

A broker who acts on behalf of a group of customers to negotiate a bulk energy rate from an energy supplier. (Source: Choose Energy)

Alternating current (AC)

An electric current that reverses its direction at regularly recurring intervals. (Source: EIA)

American Indian Coal Lease

A lease granted to a mining company to produce coal from land held in trust by the United States for Native Americans, Native American tribes, and Alaska Natives in exchange for royalties and other revenues. (Source: EIA)

AMI

Advanced Metering Infrastructure is a term denoting electricity meters that measure and record usage data at a minimum, in hourly intervals, and provide usage data to both consumers and energy companies at least once daily. (Source: EIA)

Amorphous silicon

An alloy of silica and hydrogen, with a disordered, noncrystalline internal atomic arrangement, that can be deposited in thin-film layers (a few micrometers in thickness) by a number of deposition methods to produce thin-film photovoltaic cells on glass, metal, or plastic substrates. (Source: EIA)

Ampere

The unit of measurement of electrical current produced in a circuit by 1 volt acting through a resistance of 1 Ohm. (Source: EIA)

Amp-Hours

The measure of the flow of current over one hour. (Source: Choose Energy)

AMR

Automated Meter Reading is a term denoting electricity meters that collect data for billing purposes only and transmit this data one way, usually from the customer to the distribution utility. (Source: EIA)

Anaerobic decomposition

Decomposition in the absence of oxygen, as in an anaerobic lagoon or digester, which produces CO2 and CH4. (Source: EIA)

Anaerobic lagoon

A liquid-based organic waste management installation characterized by waste residing in water at a depth of at least 6 feet for periods of 30 to 200 days. (Source: EIA)

Angle of Incidence

The angle between the direct impact of the sun’s rays and the surface of the solar panel. To get the maximum amount of solar energy, you want the panel to be perpendicular to the sun’s rays. Your solar installer will angle the solar panels to get the maximum amount of energy efficiency. (Source: Choose Energy)

ANSI

American National Standards Institute (Source: EIA)

Anthracite

The highest rank of coal; used primarily for residential and commercial space heating. It is a hard, brittle, and black lustrous coal, often referred to as hard coal, containing a high percentage of fixed carbon and a low percentage of volatile matter. The moisture content of fresh-mined anthracite generally is less than 15 percent. The heat content of anthracite ranges from 22 to 28 million Btu per ton on a moist, mineral-matter-free basis. The heat content of anthracite coal consumed in the United States averages 25 million Btu per ton, on the as-received basis (i.e., containing both inherent moisture and mineral matter). Note (Source: EIA)

Anthropogenic

Made or generated by a human or caused by human activity. The term is used in the context of global climate change to refer to gaseous emissions that are the result of human activities, as well as other potentially climate-altering activities, such as deforestation. (Source: EIA)

Antireflection Coating

A material applied to the surface of a solar panel that reduces light reflection to increase light transmission. (Source: Choose Energy)

API

The American Petroleum Institute, a trade association. (Source: EIA)

API gravity

American Petroleum Institute measure of specific gravity of crude oil or condensate in degrees. An arbitrary scale expressing the gravity or density of liquid petroleum products. The measuring scale is calibrated in terms of degrees API; it is calculated as follows (Source: EIA)

Apparent consumption, (coal)

Coal production plus imports of coal, coke, and briquets minus exports of coal, coke, and briquets plus or minus stock changes. Note (Source: EIA)

Apparent consumption, natural gas (international)

The total of an individual nation's dry natural gas production plus imports less exports. (Source: EIA)

Apparent power

The product of the voltage (in volts) and the current (in amperes). It comprises both active and reactive power. It is measured in "volt-amperes" and often expressed in "kilovolt-amperes" (kVA) or "megavolt-amperes" (MVA). See Power, Reactive Power, Real Power. (Source: EIA)

Appliance Energy Efficiency Ratings

A ratings system established by the U.S. Department of Energy to determine how efficiently appliances convert energy sources to useful energy. (Source: Choose Energy)

Aromatics

Hydrocarbons characterized by unsaturated ring structures of carbon atoms. Commercial petroleum aromatics are benzene, toluene, and xylene (BTX). (Source: EIA)

Array

Several solar panels that are connected together in a single system. (Source: Choose Energy)

Asbestos

A group of naturally occurring minerals that separate into long, thin fibers. Asbestos was used for many years to insulate and fireproof buildings. In the 1989 CBECS, information on asbestos in buildings was collected (Section R of the Buildings Questionnaire) for the U.S. Environmental Protection Agency (EPA). Asbestos treatment methods include removal, encapsulation or sealing, and enclosure behind a permanent barrier. (Source: EIA)

Ash

Impurities consisting of silica, iron, alumina, and other noncombustible matter that are contained in coal. Ash increases the weight of coal, adds to the cost of handling, and can affect its burning characteristics Ash content is measured as a percent by weight of coal on an "as received" or a "dry" (moisture-free, usually part of a laboratory analysis) basis. (Source: EIA)

ASTM

American Society for Testing and Materials (Source: EIA)

Auger mine

A surface mine in which the coal bed is removed by means of a large diameter drill. Usually operated only when the overburden becomes too thick for economical strip mining. (Source: EIA)

Auxiliary generator

A generator at the electric plant site that provides power for the operation of the electrical generating equipment itself, including related demands such as plant lighting, during periods when the electric plant is not operating and power is unavailable from the grid. A black start generator used to start main central station generators is considered to be an auxiliary generator. (Source: EIA)

Average daily production

The ratio of the total production at a mining operation to the total number of production days worked at the operation. (Source: EIA)

Average mine price

The ratio of the total value of the coal produced at the mine to the total production tonnage. (Source: EIA)

Average Open Market Sales Price (coal)

The ratio, for a specified time period, of the total value of the open market sales of coal produced at the mine to the value of the total open market sales tonnage. (Source: EIA)

Average Recovery Percentage (coal)

The percentage of coal that can be recovered from known coal reserves at reporting mines, weight averaged for all mines in the reported geographic area. (Source: EIA)

Average revenue per kilowatthour

The average revenue per kilowatthour of electricity sold by sector (residential, commercial, industrial, or other) and geographic area (State, Census division, and national) is calculated by dividing the total monthly revenue by the corresponding total monthly sales for each sector and geographic area. (Source: EIA)

Aviation gasoline (finished)

A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in aviation reciprocating engines. Fuel specifications are provided in ASTM Specification D 910 and Military Specification MIL-G-5572. Note (Source: EIA)

Backup generator

A generator that is used only for test purposes, or in the event of an emergency, such as a shortage of power needed to meet customer load requirements. (Source: EIA)

Backup power

Electric energy supplied by a utility to replace power and energy lost during an unscheduled equipment outage. (Source: EIA)

Barrel

A unit of volume equal to 42 U.S. gallons. (Source: EIA)

Barrels per stream day

The maximum number of barrels of input that a distillation facility can process within a 24-hour period when running at full capacity under optimal crude and product slate conditions with no allowance for downtime. (Source: EIA)

Base gas

The quantity of natural gas needed to maintain adequate reservoir pressures and deliverability rates throughout the withdrawal season. Base gas usually is not withdrawn and remains in the reservoir. All natural gas native to a depleted reservoir is included in the base gas volume. (Source: EIA)

Access

The customer's legal right as stipulated in his or her contract to utilize energy systems as a method of transferring energy to a home or business. (Source: Choose Energy )

Acid mine drainage

This refers to water pollution that results when sulfur-bearing minerals associated with coal are exposed to air and water and form sulfuric acid and ferrous sulfate. The ferrous sulfate can further react to form ferric hydroxide, or yellow boy, a yellow-orange iron precipitate found in streams and rivers polluted by acid mine drainage. (Source: EIA)

Acid rain

Also called acid precipitation or acid deposition, acid rain is precipitation containing harmful amounts of nitric and sulfuric acids formed primarily by sulfur dioxide and nitrogen oxides released into the atmosphere when fossil fuels are burned. It can be wet precipitation (rain, snow, or fog) or dry precipitation (absorbed gaseous and particulate matter, aerosol particles or dust). Acid rain has a pH below 5.6. Normal rain has a pH of about 5.6, which is slightly acidic. The term pH is a measure of acidity or alkalinity and ranges from 0 to 14. A pH measurement of 7 is regarded as neutral. Measurements below 7 indicate increased acidity, while those above indicate increased alkalinity. (Source: EIA)

Acquisition (foreign crude oil)

All transfers of ownership of foreign crude oil to a firm, irrespective of the terms of that transfer. Acquisitions thus include all purchases and exchange receipts as well as any and all foreign crude acquired under reciprocal buy-sell agreements or acquired as a result of a buy-back or other preferential agreement with a host government. (Source: EIA)

Acquisition (minerals)

The procurement of the legal right to explore for and produce discovered minerals, if any, within a specific area; that legal right may be obtained by mineral lease, concession, or purchase of land and mineral rights or of mineral rights alone. (Source: EIA)

Acquisition costs, mineral rights

Direct and indirect costs incurred to acquire legal rights to extract natural resources. Direct costs include costs incurred to obtain options to lease or purchase mineral rights and costs incurred for the actual leasing (e.g., lease bonuses) or purchasing of the rights. Indirect costs include such costs as brokers' commissions and expenses; abstract and recording fees; filing and patenting fees; and costs for legal examination of title and documents. (Source: EIA)

Active power

The component of electric power that performs work, typically measured in kilowatts (kW) or megawatts(MW). Also known as "real power." The terms "active" or "real" are used to modify the base term "power" to differentiate it from Reactive Power. See Power, Reactive Power, Apparent Power (Source: EIA)

Active solar

As an energy source, energy from the sun collected and stored using mechanical pumps or fans to circulate heat-laden fluids or air between solar collectors and a building. (Source: EIA)

Actual peak reduction

The actual reduction in annual peak load (measured in kilowatts) achieved by customers that participate in a utility demand-side management (DSM) program. It reflects the changes in the demand for electricity resulting from a utility DSM program that is in effect at the same time the utility experiences its annual peak load, as opposed to the installed peak load reduction capability (i.e., potential peak reduction). It should account for the regular cycling of energy efficient units during the period of annual peak load. (Source: EIA)

Afforestation

Planting of new forests on lands that have not been recently forested. (Source: EIA)

AGA

American Gas Association (Source: EIA)

Agglomerating character

Agglomeration describes the caking properties of coal. Agglomerating character is determined by examination and testing of the residue when a small powdered sample is heated to 950 degrees Centigrade under specific conditions. If the sample is "agglomerating," the residue will be coherent, show swelling or cell structure, and be capable of supporting a 500-gram weight without pulverizing. (Source: EIA)

Aggregator

A broker who acts on behalf of a group of customers to negotiate a bulk energy rate from an energy supplier. (Source: Choose Energy)

Alternating current (AC)

An electric current that reverses its direction at regularly recurring intervals. (Source: EIA)

American Indian Coal Lease

A lease granted to a mining company to produce coal from land held in trust by the United States for Native Americans, Native American tribes, and Alaska Natives in exchange for royalties and other revenues. (Source: EIA)

AMI

Advanced Metering Infrastructure is a term denoting electricity meters that measure and record usage data at a minimum, in hourly intervals, and provide usage data to both consumers and energy companies at least once daily. (Source: EIA)

Amorphous silicon

An alloy of silica and hydrogen, with a disordered, noncrystalline internal atomic arrangement, that can be deposited in thin-film layers (a few micrometers in thickness) by a number of deposition methods to produce thin-film photovoltaic cells on glass, metal, or plastic substrates. (Source: EIA)

Ampere

The unit of measurement of electrical current produced in a circuit by 1 volt acting through a resistance of 1 Ohm. (Source: EIA)

Amp-Hours

The measure of the flow of current over one hour. (Source: Choose Energy)

AMR

Automated Meter Reading is a term denoting electricity meters that collect data for billing purposes only and transmit this data one way, usually from the customer to the distribution utility. (Source: EIA)

Anaerobic decomposition

Decomposition in the absence of oxygen, as in an anaerobic lagoon or digester, which produces CO2 and CH4. (Source: EIA)

Anaerobic lagoon

A liquid-based organic waste management installation characterized by waste residing in water at a depth of at least 6 feet for periods of 30 to 200 days. (Source: EIA)

Angle of Incidence

The angle between the direct impact of the sun’s rays and the surface of the solar panel. To get the maximum amount of solar energy, you want the panel to be perpendicular to the sun’s rays. Your solar installer will angle the solar panels to get the maximum amount of energy efficiency. (Source: Choose Energy)

ANSI

American National Standards Institute (Source: EIA)

Anthracite

The highest rank of coal; used primarily for residential and commercial space heating. It is a hard, brittle, and black lustrous coal, often referred to as hard coal, containing a high percentage of fixed carbon and a low percentage of volatile matter. The moisture content of fresh-mined anthracite generally is less than 15 percent. The heat content of anthracite ranges from 22 to 28 million Btu per ton on a moist, mineral-matter-free basis. The heat content of anthracite coal consumed in the United States averages 25 million Btu per ton, on the as-received basis (i.e., containing both inherent moisture and mineral matter). Note (Source: EIA)

Anthropogenic

Made or generated by a human or caused by human activity. The term is used in the context of global climate change to refer to gaseous emissions that are the result of human activities, as well as other potentially climate-altering activities, such as deforestation. (Source: EIA)

Antireflection Coating

A material applied to the surface of a solar panel that reduces light reflection to increase light transmission. (Source: Choose Energy)

API

The American Petroleum Institute, a trade association. (Source: EIA)

API gravity

American Petroleum Institute measure of specific gravity of crude oil or condensate in degrees. An arbitrary scale expressing the gravity or density of liquid petroleum products. The measuring scale is calibrated in terms of degrees API; it is calculated as follows (Source: EIA)

Apparent consumption, (coal)

Coal production plus imports of coal, coke, and briquets minus exports of coal, coke, and briquets plus or minus stock changes. Note (Source: EIA)

Apparent consumption, natural gas (international)

The total of an individual nation's dry natural gas production plus imports less exports. (Source: EIA)

Apparent power

The product of the voltage (in volts) and the current (in amperes). It comprises both active and reactive power. It is measured in "volt-amperes" and often expressed in "kilovolt-amperes" (kVA) or "megavolt-amperes" (MVA). See Power, Reactive Power, Real Power. (Source: EIA)

Appliance Energy Efficiency Ratings

A ratings system established by the U.S. Department of Energy to determine how efficiently appliances convert energy sources to useful energy. (Source: Choose Energy)

Aromatics

Hydrocarbons characterized by unsaturated ring structures of carbon atoms. Commercial petroleum aromatics are benzene, toluene, and xylene (BTX). (Source: EIA)

Array

Several solar panels that are connected together in a single system. (Source: Choose Energy)

Asbestos

A group of naturally occurring minerals that separate into long, thin fibers. Asbestos was used for many years to insulate and fireproof buildings. In the 1989 CBECS, information on asbestos in buildings was collected (Section R of the Buildings Questionnaire) for the U.S. Environmental Protection Agency (EPA). Asbestos treatment methods include removal, encapsulation or sealing, and enclosure behind a permanent barrier. (Source: EIA)

Ash

Impurities consisting of silica, iron, alumina, and other noncombustible matter that are contained in coal. Ash increases the weight of coal, adds to the cost of handling, and can affect its burning characteristics Ash content is measured as a percent by weight of coal on an "as received" or a "dry" (moisture-free, usually part of a laboratory analysis) basis. (Source: EIA)

ASTM

American Society for Testing and Materials (Source: EIA)

Auger mine

A surface mine in which the coal bed is removed by means of a large diameter drill. Usually operated only when the overburden becomes too thick for economical strip mining. (Source: EIA)

Auxiliary generator

A generator at the electric plant site that provides power for the operation of the electrical generating equipment itself, including related demands such as plant lighting, during periods when the electric plant is not operating and power is unavailable from the grid. A black start generator used to start main central station generators is considered to be an auxiliary generator. (Source: EIA)

Average daily production

The ratio of the total production at a mining operation to the total number of production days worked at the operation. (Source: EIA)

Average mine price

The ratio of the total value of the coal produced at the mine to the total production tonnage. (Source: EIA)

Average Open Market Sales Price (coal)

The ratio, for a specified time period, of the total value of the open market sales of coal produced at the mine to the value of the total open market sales tonnage. (Source: EIA)

Average Recovery Percentage (coal)

The percentage of coal that can be recovered from known coal reserves at reporting mines, weight averaged for all mines in the reported geographic area. (Source: EIA)

Average revenue per kilowatthour

The average revenue per kilowatthour of electricity sold by sector (residential, commercial, industrial, or other) and geographic area (State, Census division, and national) is calculated by dividing the total monthly revenue by the corresponding total monthly sales for each sector and geographic area. (Source: EIA)

Aviation gasoline (finished)

A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in aviation reciprocating engines. Fuel specifications are provided in ASTM Specification D 910 and Military Specification MIL-G-5572. Note (Source: EIA)

Backup generator

A generator that is used only for test purposes, or in the event of an emergency, such as a shortage of power needed to meet customer load requirements. (Source: EIA)

Backup power

Electric energy supplied by a utility to replace power and energy lost during an unscheduled equipment outage. (Source: EIA)

Barrel

A unit of volume equal to 42 U.S. gallons. (Source: EIA)