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Browse terms related to these fuel groups:alternative fuels|coal|electricity|natural gas|nuclear|petroleum|renewable


N2O:   Nitrous Oxide

NAAQS:   National Ambient Air Quality Standards

NAICS (North American Industry Classification System):  A coding system developed jointly by the United States, Canada, and Mexico to classify businesses and industries according to the type of economic activity in which they are engaged. NAICS replaces the Standard Industrial Classification (SIC) codes.

Name plate:  A metal tag attached to a machine or appliance that contains information such as brand name, serial number, voltage, power ratings under specified conditions, and other manufacturer supplied data.

Name plate capacity:  See Generator name plate capacity (installed).

Naphtha:  A generic term applied to a refined or partially refined petroleum fraction with an approximate boiling range between 122 degrees and 400 degrees Fahrenheit.

Naphtha less than 401 degrees Fahrenheit:  See Petrochemical feedstocks.

Naphtha-type jet fuel:  A fuel in the heavy naphtha boiling range having an average gravity of 52.8 degrees API, 20% to 90% distillation temperatures of 290 degrees to 470 degrees Fahrenheit, and meeting Military Specification MIL-T-5624L (Grade JP-4).It is used primarily for military turbojet and turboprop aircraft engines because it has a lower freeze point than other aviation fuels and meets engine requirements at high altitudes and speeds. Note: Beginning with January 2004 data, naphtha-type jet fuel is included in Miscellaneous Products .

Naphthas:  Refined or partly refined light distillates with an approximate boiling point range between 122 and 400 degrees Fahrenheit. Blended further or mixed with other materials, they make high-grade motor gasoline or jet fuel. Also, used as solvents, petrochemical feedstocks, or as raw materials for the production of town gas.

NARUC:  See National Association of Regulatory Utility Commissioners.

National Association of Regulatory Utility Commissioners (NARUC):  An affiliation of the public service commissioners to promote the uniform treatment of members of the railroad, public utilities, and public service commissions of the 50 states, the District of Columbia, the Commonwealth of Puerto Rico, and the territory of the Virgin Islands.

National Defense Authorization Act:  The federal law, enacted in 1994 and amended in 1995, that required the Secretary of Energy to prepare the Baseline Report.

National priorities list:  The Environmental Protection Agency's list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial action under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The list is based primarily on the score a site receives from the Environmental Protection Agency Hazard Ranking System. The Environmental Protection Agency is required to update the National Priorities List at least once a year.

National Rural Electric Cooperative Association (NRECA):  A national organization dedicated to representing the interests of cooperative electric utilities and the consumers they serve. Members come from the 46 states that have an electric distribution cooperative.

National Uranium Resource Evaluation (NURE):  A program begun by the U.S. Atomic Energy Commission (AEC) in 1974 to make a comprehensive evaluation of U.S. uranium resources and continued through1983 by the AEC's successor agencies, the Energy Research and Development Administration (ERDA), and the Department of Energy (DOE).The NURE program included aerial radiometric and magnetic surveys, hydrogeochemical and stream sediment surveys, geologic drilling in selected areas, geophysical logging of selected bore holes, and geologic studies to identify and evaluate geologic environments favorable for uranium.

Native gas:  Gas in place at the time that a reservoir was converted to use as an underground storage reservoir in contrast to injected gas volumes.

Native load (electric):  The end-use customers that the Load-Serving Entity is obligated to serve. NERC definition

Natural gas:  A gaseous mixture of hydrocarbon compounds, the primary one being methane.

Natural gas field facility:  A field facility designed to process natural gas produced from more than one lease for the purpose of recovering condensate from a stream of natural gas; however, some field facilities are designed to recover propane, normal butane, pentanes plus, etc., and to control the quality of natural gas to be marketed.

Natural gas gross withdrawals:  Full well-stream volume of produced natural gas, excluding condensate separated at the lease.

Natural gas hydrates:  Solid, crystalline, wax-like substances composed of water, methane, and usually a small amount of other gases, with the gases being trapped in the interstices of a water-ice lattice. They form beneath permafrost and on the ocean floor under conditions of moderately high pressure and at temperatures near the freezing point of water.

Natural gas lease production:  Gross withdrawals of natural gas minus gas production injected on the lease into producing reservoirs, vented, flared, used as fuel on the lease, and nonhydrocarbon gases removed in treating or processing operations on the lease.

Natural Gas Liquids (NGL):  A group of hydrocarbons including ethane, propane, normal butane, isobutane, and natural gasoline. Generally include natural gas plant liquids and all liquefied refinery gases except olefins.

Natural gas liquids production:  The volume of natural gas liquids removed from natural gas in lease separators, field facilities, gas processing plants, or cycling plants during the report year.

Natural gas marketed production:  Gross withdrawals of natural gas from production reservoirs, less gas used for reservoir repressuring, nonhydrocarbon gases removed in treating and processing operations, and quantities vented and flared.

Natural gas marketer:  A company that arranges purchases and sales of natural gas. Unlike pipeline companies or local distribution companies, a marketer does not own physical assets commonly used in the supply of natural gas, such as pipelines or storage fields. A marketer may be an affiliate of another company, such as a local distribution company, natural gas pipeline, or producer, but it operates independently of other segments of the company. In States with residential choice programs, marketers serve as alternative suppliers to residential users of natural gas, which is delivered by a local distribution company.

Natural gas plant liquids (NGPL):  Those hydrocarbons in natural gas that are separated as liquids at natural gas processing, fractionating, and cycling plants. Products obtained include ethane, liquefied petroleum gases (propane, normal butane, and isobutane), and natural gasoline. Component products may be fractionated or mixed. Lease condensate and plant condensate are excluded. Note: Some EIA publications categorize NGPL production as field production, in accordance with definitions used prior to January 2014.

Natural gas plant liquids (NGPL) production:  The extraction of gas plant liquids constituents such as ethane, propane, normal butane, isobutane, and natural gasoline, sometimes referred to as extraction loss. Usually reported in barrels or gallons, but may be reported in cubic feet for purposes of comparison with dry natural gas volumes.

Natural Gas Policy Act of 1978 (NGPA):  Signed into law on November 9, 1978, the NGPA is a framework for the regulation of most facets of the natural gas industry.

Natural gas processing plant:  Facilities designed to recover natural gas liquids from a stream of natural gas that may or may not have passed through lease separators and/or field separation facilities. These facilities control the quality of the natural gas to be marketed. Cycling plants are classified as gas processing plants.

Natural gas production:  See Dry natural gas production.

Natural gas sweetening:  The process of removing hydrogen sulfide (H2S), carbon dioxide (CO2), and mercaptans from natural gas to make it suitable for transport and sale. Sour natural gas must be sweetened because H2S is highly toxic, and H2S and CO2 corrode natural gas pipelines.

Natural Gas Used for Injection:  Natural gas used to pressurize crude oil reservoirs in an attempt to increase oil recovery or in instances where there is no market for the natural gas. Natural gas used for injection is sometimes referred to as repressuring.

Natural gas utility demand-side management (DSM) program sponsor:  A DSM (demand-side management) program sponsored by a natural gas utility that suggests ways to increase the energy efficiency of buildings, to reduce energy costs, to change the usage patterns, or to promote the use of a different energy source.

Natural gas, "dry":  See Dry natural gas.

Natural gasoline:  A commodity product commonly traded in NGL markets that comprises liquid hydrocarbons (mostly pentanes and hexanes) and generally remains liquid at ambient temperatures and atmospheric pressure. Natural gasoline is equivalent to pentanes plus.

Natural Gasoline and Isopentane:  A mixture of hydrocarbons, mostly pentanes and heavier, extracted from natural gas, that meets vapor pressure, end-point, and other specifications for natural gasoline set by the Gas Processors Association. Includes isopentane which is a saturated branch-chain hydrocarbon, (C5H12), obtained by fractionation of natural gasoline or isomerization of normal pentane.

Natural reservoir pressure:  The energy within an oil or gas reservoir that causes the oil or gas to rise (unassisted by other forces) to the earth's surface when the reservoir is penetrated by an oil or gas well. The energy may be the result of "dissolved gas drive," "gas cap drive," or "water drive." Regardless of the type of drive, the principle is the same: the energy of the gas or water, creating a natural pressure, forces the oil or gas to the well bore.

Natural streamflow:  The rate of flow of water past a given point of an uncontrolled stream or regulated streamflow adjusted to eliminate the effects of reservoir storage or upstream diversions at a set time interval.

Natural uranium:  Uranium with the U-235 isotope present at a concentration of 0.711 percent (by weight), that is, uranium with its isotopic content exactly as it is found in nature.

Near-month contract for energy futures:  The near-month contract, a term used in energy futures and options trading and other transactions, is the active contract with the shortest time to maturity. It is the contract that will expire first (often, but not always, within the next month). The near month is also called the prompt month, the front month, the lead month, and the first nearby.

NERC:  See North American Electric Reliability Corporation.

Net actual interchange (electric):  The algebraic sum of all metered interchange over all interconnections between two physically Adjacent Balancing Authority Areas. NERC definition

Net cell shipments:  Represents the difference between cell shipments and cell purchases.

Net electricity consumption:  Consumption of electricity computed as generation, plus imports, minus exports, minus transmission and distribution losses.

Net energy for load (electric):  Net Balancing Authority Area generation, plus energy received from other Balancing Authority Areas, less energy delivered to Balancing Authority Areas through interchange. It includes Balancing Authority Area losses but excludes energy required for storage at energy storage facilities. NERC definition

Net energy for system:  The sum of energy an electric utility needs to satisfy their service areas, including full and partial requirements consumers.

Net generation:  The amount of gross generation less the electrical energy consumed at the generating station(s) for station service or auxiliaries. Note: Electricity required for pumping at pumped-storage plants is regarded as electricity for station service and is deducted from gross generation.

Net head:  The gross head minus all hydraulic losses except those chargeable to the turbine.

Net income:  Operating income plus other income and extraordinary income less operating expenses, taxes, interest charges, other deductions, and extraordinary deductions.

Net interstate flow of electricity:  The difference between the sum of electricity sales and losses within a state and the total amount of electricity generated within that state. A positive number indicates that more electricity (including associated losses) came into the state than went out of the state during the year; conversely, a negative number indicates that more electricity (including associated losses) went out of the state than came into the state.

Net metering:  Utility tariffs or billing programs that allow certain types of customers to reduce the volume of billed electricity supplied by the grid within a defined billing period. The reduced volume of billed electricity takes into account the amount of electricity that the customer sold back to the grid during times when self-generation (typically powered by a renewable energy source) exceeded consumption.

Net module shipments:  Represents the difference between module shipments and module purchases. When exported, incomplete modules and unencapsulated cells are also included.

Net operable capacity:  Total owned capacity less in operable capacity.

Net photovoltaic module shipment:  The difference between photovoltaic module shipments and photovoltaic module purchases.

Net profits interest:  A contractual arrangement under which the beneficiary, in exchange for consideration paid, receives a stated percentage of the net profits. That type of arrangement is considered a nonoperating interest, as distinguished from a working interest, because it does not involve the rights and obligations of operating a mineral property (costs of exploration, development, and operation). The net profits interest does not bear any part of net losses.

Net Receipts:  The difference between total movements into and total movements out of each PAD District by pipeline, tanker, and barge.

Net summer capacity:  The maximum output, commonly expressed in megawatts (MW), that generating equipment can supply to system load, as demonstrated by a multi-hour test, at the time of summer peak demand (period of June 1 through September 30.) This output reflects a reduction in capacity due to electricity use for station service or auxiliaries.

Net winter capacity:  The maximum output, commonly expressed in megawatts (MW), that generating equipment can supply to system load, as demonstrated by a multi-hour test, at the time of peak winter demand (period of December 1 through February 28). This output reflects a reduction in capacity due to electricity use for station service or auxiliaries.

Netback purchase:  Refers to a crude oil purchase agreement wherein the price paid for the crude is determined by sales prices of the types of products that are derivable from that crude as well as other considerations (e.g., transportation and processing costs). Typically, the price is calculated based on product prices extant on or near the cargo's date of importation.

New field:  A field discovered during the report year.

New field discoveries:  The volumes of proved reserves of crude oil, natural gas, and/or natural gas liquids discovered in new fields during the report year.

New reservoir:  A reservoir discovered during the report year.

NGL:  See Natural gas liquids.

NGPA:  See Natural Gas Policy Act of 1978.

NGPL:   Natural Gas Plant Liquids

NGV:   Natural Gas Vehicle

Nitrogen dioxide:  A compound of nitrogen and oxygen formed by the oxidation of nitric oxide (NO) which is produced by the combustion of solid fuels.

Nitrogen oxides (NOx):  Compounds of nitrogen and oxygen produced by the burning of fossil fuels.

Nitrous oxide (N2O):  A colorless gas, naturally occurring in the atmosphere. Nitrous oxide has a 100-year Global Warming Potential of 310.

No. 1 diesel fuel:  A light distillate fuel oil that has a distillation temperature of 550 degrees Fahrenheit at the 90-percent recovery point and meets the specifications defined in ASTM Specification D 975. It is used in high speed diesel engines generally operated under frequent speed and load changes, such as those in city buses and similar vehicles. See No. 1 distillate.

No. 1 distillate:  A light petroleum distillate that can be used as either a diesel fuel (see No. 1 diesel fuel) or a fuel oil (see No. 1 fuel oil).

No. 1 fuel oil:  A light distillate fuel oil that has distillation temperatures of 400 degrees Fahrenheit at the 10-percent recovery point and 550 degrees Fahrenheit at the 90-percent recovery point and meets the specifications defined in ASTM Specification D 396. It is used primarily as fuel for portable outdoor stoves and portable outdoor heaters. See No. 1 Distillate.

No. 2 diesel fuel:  A distillate fuel oil that has a distillation temperature of 640 degrees Fahrenheit at the 90-percent recovery point and meets the specifications defined in ASTM Specification D 975. It is used in high-speed diesel engines that are generally operated under uniform speed and load conditions, such as those in railroad locomotives, trucks, and automobiles. See No. 2 Distillate.

No. 2 distillate:  A petroleum distillate that can be used as either a diesel fuel (see No. 2 diesel fuel) or a fuel oil (see No. 2 fuel oil).

No. 2 fuel oil (heating oil):  A distillate fuel oil that has distillation temperatures of 400 degrees Fahrenheit at the 10-percent recovery point and 640 degrees Fahrenheit at the 90-percent recovery point and meets the specifications defined in ASTM Specification D 396. It is used in atomizing type burners for domestic heating or for moderate capacity commercial/industrial burner units. See No. 2 Distillate.

No. 2 fuel oil and No. 2 diesel sold to consumers for all other end uses:  Those consumers who purchase fuel oil or diesel fuel for their own use including commercial/institutional buildings (including apartment buildings), manufacturing and nonmanufacturing establishments, farms (including farm houses), motor vehicles, commercial or private boats, military, governments, electric utilities, railroads, construction, logging or any other nonresidential end-use purpose.

No. 2 fuel oil sold to private homes for heating:  Private household customers who purchase fuel oil for the specific purpose of heating their home, water heating, cooking, etc., excluding farm houses, farming and apartment buildings.

No. 4 fuel oil:  A distillate fuel oil made by blending distillate fuel oil and residual fuel oil stocks. It conforms with ASTM Specification D 396 or Federal Specification VV-F-815C and is used extensively in industrial plants and in commercial burner installations that are not equipped with preheating facilities. It also includes No. 4 diesel fuel used for low- and medium-speed diesel engines and conforms to ASTM Specification D 975.

No. 5 Residual fuel oil:  A residual fuel oil of medium viscosity, used in steam-powered vessels in government service and power plants, which is also known as “Navy Special” and is defined in Military Specification MIL-F-859E, including Amendment 2 (NATO Symbol F-770). See residual fuel oil.

No. 6 Residual fuel oil:  Includes Bunker C fuel oil and is used for the production of electric power, space heating, vessel bunkering, and various industrial purposes. See residual fuel oil.

NOx:  See Nitrogen oxides

NOAA:  National Oceanic and Atmospheric Administration.

NOAA division:  One of the 345 weather divisions designated by the National Oceanic and Atmospheric Administration (NOAA) encompassing the 48 contiguous states. These divisions usually follow county borders to encompass counties with similar weather conditions. The NOAA division does not follow county borders when weather conditions vary considerably within a county; such is likely to happen when the county borders the ocean or contains high mountains. A state contains an average of seven NOAA divisions; a NOAA division contains an average of nine counties.

Noload loss:  Power and energy lost by an electric system when not operating under demand.

Nominal dollars:  A measure used to express nominal price.

Nominal price:  The price paid for a product or service at the time of the transaction. Nominal prices are those that have not been adjusted to remove the effect of changes in the purchasing power of the dollar; they reflect buying power in the year in which the transaction occurred.

Non-biomass waste:  Material of non-biological origin that is a byproduct or a discarded product. "Non-biomass waste" includes municipal solid waste from non-biogenic sources, such as plastics, and tire-derived fuels.

Non-combustion use:  Fossil fuels (coal, natural gas, and petroleum products) that are not burned to release energy and instead used directly as construction materials, chemical feedstocks, lubricants, solvents, waxes, and other products. “Non-combustion use” is sometimes used synonymously with “Nonfuel use (of energy).”

Non-Combustion Use:  Fossil fuels (coal, natural gas, and petroleum products) that are not burned to release energy and instead used directly as construction materials, chemical feedstocks, lubricants, solvents, waxes, and other products. “Non-combustion use” is sometimes used synonymously with “Nonfuel use (of energy).”

Non-marketed energy:  Energy consumed in the end-use sectors that isn’t purchased, such as solar energy captured by a rooftop solar photovoltaic system, geothermal energy used by ground-source heat pumps, or wood collected from your backyard.

Non-metallurgical coal:  Coal that is not expected to be used in coke ovens to produce coke.

Nonassociated natural gas:  Natural gas that is not in contact with significant quantities of crude oil in the reservoir. See natural gas.

Nonattainment area:  Any area that does not meet the national primary or secondary ambient air quality standard established by the Environmental Protection Agency for designated pollutants, such as carbon monoxide and ozone.

Nonbranded product:  Any refined petroleum product that is not a branded product.

Noncoincident demand:  Sum of two or more demands on individual systems that do not occur in the same demand interval.

Noncoincidental peak load:  The sum of two or more peak loads on individual systems that do not occur in the same time interval. Meaningful only when considering loads within a limited period of time, such as a day, week, month, a heating or cooling season, and usually for not more than 1 year.

Nonconventional plant (uranium):  A facility engineered and built principally for processing of uraniferous solutions that are produced during in situ leach mining, from heap leaching, or in the manufacture of other commodities, and the recovery, by chemical treatment in the plant's circuits, of uranium from the processing solutions.

Nondedicated vehicle:  A motor vehicle capable of operating on an alternative fuel and /or on either gasoline or diesel.

Nonfirm power:  Power or power-producing capacity supplied or available under a commitment having limited or no assured availability.

Nonfuel components:  Components that are not associated with a particular fuel. These include, but are not limited to, control spiders, burnable poison rod assemblies, control rod elements, thimble plugs, fission chambers, primary and secondary neutron sources, and BWR (boiling water reactor) channels.

Nonfuel use (of energy):  Use of energy as feedstock or raw material input.

Nonfungible product:  A gasoline blend or blendstock that cannot be shipped via existing petroleum product distribution systems because of incompatibility problems. Gasoline/ethanol blends, for example, are contaminated by water that is typically present in petroleum product distribution systems.

Nonhydrocarbon gases:  Typical nonhydrocarbon gases that may be present in reservoir natural gas, such as carbondioxide, helium, hydrogen sulfide, and nitrogen.

Nonmethane volatile organic compounds (NMVOC):  Organic compounds, other than methane, that participate in atmospheric photochemical reactions.

Nonoperating interest:  Any mineral lease interest (e.g., royalty, production payment, net profits interest) that does not involve the rights and obligations of operating a mineral property.

Nonproducing reservoir:  Reservoir in which oil and/or gas proved reserves have been identified, but which did not produce during the report year to the owned or contracted interest of the reporting company regardless of the availability and/or operation of production, gathering, or transportation facilities.

Nonrenewable fuels:  Fuels that cannot be easily made or "renewed," such as oil, natural gas, and coal.

Nonrequirements consumer:  A wholesale consumer (unlike a full or partial requirements consumer) that purchases economic or coordination power to supplement their own or another system's energy needs.

Nonresidential building:  A building used for some purpose other than residential. Nonresidential buildings comprise three groups commercial, manufacturing/industrial, and agricultural.

Nonroad alternative fuel vehicle (nonroad AFV):  An alternative fuel vehicle designed for off-road operation and use for surface/air transportation, industrial, or commercial purposes. Nonroad AFVs include forklifts and other industrial vehicles, rail locomotives, self-propelled electric rail cars, aircraft, airport service vehicles, construction vehicles, agricultural vehicles, and marine vessels. Recreational AFVs (golf carts, snow mobiles, pleasure watercraft, etc.) are excluded from the definition.

Nonspinning reserve:  The generating capacity not currently running but capable of being connected to the bus and load within a specified time.

Nonutility generation:  Electric generation by end-users, or small power producers under the Public Utility Regulatory Policies Act, to supply electric power for industrial, commercial, andmilitary operations, or sales to electric utilities.

Nonutility power producer:  A corporation, person, agency, authority, or other legal entity or instrumentality that owns or operates facilities for electric generation and is not an electric utility. Nonutility power producers include qualifying cogenerators, qualifying small power producers, and other nonutility generators (including independent power producers). Non-utility power producers are without a designated franchised service area and do not file forms listed in the Code of Federal Regulations, Title 18, Part 141

NOPR:   Notice of Proposed Rulemaking

Normal butane (C4H10):  A straight-chain saturated (paraffinic) hydrocarbon extracted from both natural gas and refinery gas streams, which is gaseous at standard temperature and pressure. It is a colorless gas that boils at a temperature of 31 degrees Fahrenheit.

North American Electric Reliability Corporation (NERC):  A nonprofit corporation formed in 2006 as the successor to the North American Electric Reliability Council established to develop and maintain mandatory reliability standards for the bulk electric system, with the fundamental goal of maintaining and improving the reliability of that system. NERC consists of regional reliability entities covering the interconnected power regions of the contiguous United States, Canada, and Mexico. See the North American Electric Reliability Corporation (NERC) Regions.

North American Industry Classification System (NAICS):  A new classification scheme, developed by the Office of Management and Budget to replace the Standard Industrial Classification (SIC) System, that categorizes establishments according to the types of production processes they primarily use.

NRECA:  See National Rural Electric Cooperative Association

Nuclear electric power (nuclear power):  Electricity generated by the use of the thermal energy released from the fission of nuclear fuel in a reactor.

Nuclear fuel:  Fissionable materials that have been enriched to such a composition that, when placed in a nuclear reactor, will support a self-sustaining fission chain reaction, producing heat in a controlled manner for process use.

Nuclear reactor:  An apparatus in which a nuclear fission chain reaction can be initiated, controlled, and sustained at a specific rate. A reactor includes fuel (fissionable material), moderating material to control the rate of fission, a heavy-walled pressure vessel to house reactor components, shielding to protect personnel, a system to conduct heat away from the reactor, and instrumentation for monitoring and controlling the reactor's systems.

NUG:   Nonutility Generator

Number of mines:  The number of mines, or mines collocated with preparation plants or tipples, located in a particular geographic area (State or region). If a mine is mining coal across two counties within a State, or across two States, then it is counted as two operations. This is done so that EIA can separate production by State and county.

Number of mining operations:  The number of mining operations includes preparation plants with greater than 5,000 total direct labor hours. Mining operations that consist of a mine and preparation plant, or a preparation plant only, will be counted as two operations if the preparation plant processes both underground and surface coal. Excluded are silt, culm, refuse bank, slurry dam, and dredge operations except for Pennsylvania anthracite. Excludes mines producing less than 10,000 short tons of coal during the year.

NURE:  See National Uranium Resource Evaluation

Nymex:  New York Mercantile Exchange