# Glossary A B C D E F G H I J K L M N O P Q R S T U V W XYZ Search glossary terms: 

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

### E
E85: A fuel containing a mixture of 85 percent ethanol an d 15 percent gasoline. See Motor gasoline (finished)

. E95: A fuel containing a mixture of 95 percent ethanol a nd 5 percent gasoline EAR: Estimated Additional Resources Economy of scale: The principle that larger production facilities have lower unit costs than smaller facilities. Effective full-power days: The number of effective full-power days produced by a u nit is a measure of the unit's energy generation. It is determined using the following rati o Heat generation (planned or actual) in megawatt days thermal (MWdt) (dividedby) Licensed thermal power in megawatts thermal (MWt). EIA: The Energy Information Administration. An independe nt agency within the U.S. Department of Energy that de velops surveys, collects energy data, and analyzes and models energy issu es. The Agency must meet the requests of Congress, other elements within the Department of Energy, Feder al Energy Regulatory Commission, the Executive Branch, its o wn independent needs, and assist the general public, or oth er interest groups, without taking a policy position. Se e more information about EIA at http://www.eia.gov/about/ EIS: Environmental Impact Statement Electric baseboard: An individual space heater with electric resistance coils m ounted behind shallow panels along baseboards. Electric baseboards rely on passive convection to di stribute heated air to the space. Electric current: The flow of electric charge. The preferred unit of m easure is the ampere. Electric energy: The ability of an electric current to produce work, heat, light, or other forms of energy. It is measured in kilowatthours. Electric expenses: The cost of labor, material, and expenses incurred in o perating a facility's prime movers, generators, auxiliary apparatus, switching gear, and other electric eq uipment for each of the points where electricity enters t he transmission or distribution grid. Electric generation: See Gross generation and Net generation

. Electric generation industry: Stationary and mobile generating units that are conn ected to the electric power grid and can generate electricity. The electric generation industry i ncludes the "electric power sector" (utility generators and independent 

## Page 1 of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=Epower producers) and industrial and commercial power gen erators, including combined-heat-and-power producers, bu t

excludes units at single-family dwellings. Electric generator: A facility that produces only electricity, commonly expressed in kilowatthours (kWh) or megawatthours (MWh). Electric generators include electric utilities and independent power producers. Electric hybrid vehicle: An electric vehicle that either (1) operates solely on e lectricity, but contains an internal combustion motor that generates additional electricity (series hybrid ); or (2) contains an electric system and an internal comb ustion system and is capable of operating on either system (parall el hybrid). Electric industry reregulation: The design and implementation of regulatory practices to be applied to the remaining traditional utilities after the electric power industry has been restructured. Reregulation applies to those ent ities that continue to exhibit characteristics of a natural monopoly. Reregul ation could employ the same or different regulatory pra ctices as those used before restructuring. Electric industry restructuring: The process of replacing a monopolistic system of electric utility suppliers with competing sellers, allowing individual retail customers to choose the ir supplier but still receive delivery over the power line s of the local utility. It includes the reconfiguration of vertically-int egrated electric utilities. Electric motor vehicle: A motor vehicle powered by an electric motor that draws current from rechargeable storage batteries, fuel cells, photovoltaic arrays, or other sources of electric current. Electric non-utility: Any entity that generates, transmits, or sells electrici ty, or sells or trades electricity services and products, where costs are not established and recovered by re gulatory authority. Examples of these entities include, bu t are not limited to, independent power producers, power ma rketers and aggregators (both wholesale and retail), me rchant transmission service providers, self-generation entities, and cogeneration firms with Qualifying Facility Status. Electric operating expenses: Summation of electric operation-related expenses, such a s operation expenses, maintenance expenses, depreciation expenses, amortization, t axes other than income taxes, Federal income taxes, other income taxes, provision for deferred income taxes, provision for deferred income-credit, and investment tax credit adjustment. Electric plant (physical): A facility containing prime movers, electric generators, and auxiliary equipment for converting mechanical, chemical, and/or fission energy into electric en ergy. Electric plant acquisition adjustment: The difference between (a) the cost to the responde nt utility of an electric plant acquired as an operating unit or system by purchase and ( b) the depreciated original cost, estimated if not known , of such property. Electric power: The rate at which electric energy is transferred. Elect ric power is measured by capacity and is commonly expressed in megawatts (MW). Electric power grid: A system of synchronized power providers and consumers connecte d by transmission and distribution lines and operated by one or more control centers. In th e continental United States, the electric power grid con sists of three systems the Eastern Interconnect, the Western Interconnect, and the Texas Interconnect. In Alaska and Hawaii, several systems encompass areas smaller than the State (e.g., the in terconnect serving Anchorage, Fairbanks, and the Kenai Peninsula; individual islands). Electric power plant: A station containing prime movers, electric generators, and auxiliary equipment for converting mechanical, chemical, and/or fission energy into electric en ergy. 

## Page 2of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EElectric power sector: An energy-consuming sector that consists of electricity only and combined heat and power(CHP)

plants whose primary business is to sell electricity, or electr icity and heat, to the public--i.e., North American Ind ustry Classification System 22 plants. See also Combined heat and power (CHP) plantand Electricity only plant

. Electric power system: An individual electric power entity--a company; an elect ric cooperative; a public electric supply corporation as the Tennessee Valley Authority; a similar F ederal department or agency such as the Bonneville Power Administration; the Bureau of Reclamation or the Corp s of Engineers; a municipally owned electric department o ffering service to the public; or an electric public utility distri ct (a "PUD"); also a jointly owned electric supply projectsuch as the Keystone. Electric pump for well water: This pump forces the water from a well below ground level up into the water pipes that circulate through the house. When this pump is not workin g, there is a limited supply of running water in the h ouse. Electric rate: The price set for a specified amount and type of electr icity by class of service in an electric rate schedule or sales contract. Electric rate schedule: A statement of the electric rate and the terms and con ditions governing its application, including attendant contract terms and conditions that have been acce pted by a regulatory body with appropriate oversight au thority. Electric system loss: Total energy loss from all causes for an electric utility. Electric system reliability: The degree to which the performance of the elements of the electrical system results in power being delivered to consumers within accepted standards and in the amount desired. Reliability encompasses two concepts, adequacy and security. Adequacy implies that there are suff icient generation and transmission resources installed an d available to meet projected electrical demand plus reserve s for contingencies. Security implies that the system will re main intact operationally (i.e., will have sufficient availabl e operating capacity) even after outages or other equip ment failure. The degree of reliability may be measured by the frequency, duration, and magnitude of adverse effects on consumer service. Electric utility: A corporation, person, agency, authority, or other leg al entity or instrumentality aligned with distribution facilities for delivery of electric energy for use primaril y by the public. Included are investor-owned electric utili ties, municipal and State utilities, Federal electric utilities, and ru ral electric cooperatives. A few entities that are tariffbased and corporately aligned with companies that own distribution facilities are also included. Electric utility company: See Electric utility

. Electric utility divestiture: The separation of one electric utility function from others through the selling of the management and ownership of the assets related to that function. Itis most commonly associated with selling generation assets so they are no longer owned or controlled by the shareholders t hat own the company's transmission and distribution assets. Electric utility generator: A generator that is owned by an electric utility, (see definition of electric utility ) or a jointly owned generator with the greatest share of the generator be ing electric utility owned. Note: If two or more owner s have equal shares of ownership in a generator, it is considered to be an electric utility generator if any one of the owners meets the definition of electric utility. Electric utility restructuring: The introduction of competition into at least the ge neration phase of electricity production, with a corresponding decrease in regulatory control. Electric utility sector: The electric utility sector consists of privately and public ly owned establishments that generate, transmit, distribute, or sell electricity primarily for useby the public and that meet the definition of an ele ctric utility. Non utility power producers are not included in the electric sector. Electric zone: A portion of the grid controlled by the independentsystem operator. 

## Page 3 of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EElectrical system energy losses: The amount of energy lost during generation, transmi ssion, and distribution of electricity,

including plant and unaccounted for use. Electricity: A form of energy characterized by the presence and motio n of elementary charged particles generated by friction, induction, or chemical change. Electricity broker: An entity that arranges the sale and purchase of electr ic energy, the transmission of electricity, and/or other related services between buyers and sellers but does n ot take title to any of the power sold. Electricity congestion: A condition that occurs when insufficient transmission cap acity is available to implement all of the desired transactions simultaneously. Electricity demand: The rate at which energy is delivered to loads and sche duling points by generation, transmission, and distribution facilities. Electricity demand bid: A bid into the power exchange indicating a quantity of energy or an ancillary service that an eligible customer is willing to purchase and, if relevant, the maximum price that the customer is willing to pay. Electricity generation: The process of producing electric energy or the amount o f electric energy produced by transforming other forms of energy, commonly expressed in kilowatthours( kWh) or megawatthours (MWh). Electricity generation, gross: See Gross generation

. Electricity generation, net: See Net generation

. Electricity only plant: A plant designed to produce electricity only. See also C ombined heat and power (CHP) plant. Electricity paid by household: The household paid the electric utility company directly for all household uses of electricity (such as water heating, space heating, air-conditioning, cooking, lighting, and operating appliances.) Bills pai d by a third party are not counted as paid by the household. Electricity sales: The amount of kilowatthours sold in a given period oftime; usually grouped by classes of service, such as residential, commercial, industrial, and other. "Other"sales include sales for public street and highway lighting and other sales to public authorities, sales to railroads and railways, and interdepartmental sales. Electrochemical process: The direct process end use in which electricity is used to ca use a chemical transformation. Major uses of electrochemical process occur in the aluminum industry in which alumina is reduced to molten aluminum metal and oxygen, and in the alkalies and chlorine industry, in which brine is separated into caustic soda, chlorine, and hydr ogen. Elution: Activities of removing "elutes" a material (uranium) adsorbed on ion exchange resin from the "eluant" solution

. Emergency: The failure of an electric power system to generate or deliver electric power as normally intended, resulting in the cut-off or curtailment of service. Emergency backup generation: The use of electric generators only during interruptio ns of normal power supply. Emergency energy: Electric energy provided for a limited duration, int ended only for use during emergency conditions. Emissions: Anthropogenic releases of gases to the atmosphere. In t he context of global climate change, they consist of radiatively important greenhouse gases (e.g., the relea se of carbon dioxide during fuel combustion). Emissions coefficient: A unique value for scaling emissions to activity data in t erms of a standard rate of emissions per unit of activity (e.g., pounds of carbon dioxide emitted per B tu of fossil fuel consumed). 

## Page 4of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EEnd user: A firm or individual that purchases products for its ow n consumption and not for resale (i.e., an ultimate

consumer). Ending stocks: Primary stocks of crude oil and petroleum products held i n storage as of 12 midnight on the last day of the month. Primary stocks include crude oil or petroleum produ cts held in storage at (or in) leases, refineries, natura l gas processing plants, pipelines, tank farms, and bulk terminal s that can store at least 50,000 barrels of petroleum p roducts or that can receive petroleum products by tanker, barge, orpipeline. Crude oil that is in-transit by water from Alaska or that is stored on Federal leases or in the Strategic Petroleum Reserve is included. Primary Stocks exclude stocks of foreign or igin that are held in bonded warehouse storage. Energy: The capacity for doing work as measured by the capability of doing work (potential energy) or the conversion of this capability to motion (kinetic energy). Energy has several fo rms, some of which are easily convertible and can be changed to another form useful for work. Most of the world's convert ible energy comes from fossil fuels that are burned to pr oduce heat that is then used as a transfer medium to mechanical or o ther means in order to accomplish tasks. Electrical energy i s usually measured in kilowatthours, while heat energy is usu ally measured in British thermal units (Btu). Energy assistance program: See Low Income Home Energy Assistance Program

. Energy audit: A program carried out by a utility company in which an auditor inspects a home and suggests ways energy can be saved. Energy broker system: Introduced into Florida by the Public Service Commission , the energy broker system is a system for exchanging information that allows utilities to efficien tly exchange hourly quotations of prices at which each is w illing to buy and sell electric energy. For the broker system to operate, utility systems must have in place bilateral agreements between all potential parties, must have transmission arrangements between all potential parties, and must have transmission arrangements that allow the exchanges to take place. Energy charge: That portion of the charge for electric service based up on the electric energy (kWh) consumed or billed. Energy conservation features: This includes building shell conservation features, HVAC conservation features, lighting conservation features, any conservation features, and otherconservation features incorporated by the building. Howe ver, this category does not include any demand-side management (DSM ) program participation by the building. Any DSM program participation is included in the DSM Programs. Energy consumption: The use of energy as a source of heat or power or as a raw material input to a manufacturing process. Energy deliveries: Energy generated by on electric utility system and deliver ed to another system through one or more transmission lines. Energy demand: The requirement for energy as an input to provide p roducts and/or services. Energy effects: The changes in aggregate electricity use (measured in me gawatthours) for consumers that participate in a utility DSM (demand-side management) program. Energy e ffects represent changes at the consumer's meter (i.e., excl ude transmission and distribution effects) and reflect only acti vities that are undertaken specifically in response to util ityadministered programs, including those activities implemen ted by third parties under contract to the utility. To t he extent possible, Energy effects should exclude non-program related effects such as changes in energy usage attributable to non participants, government-mandated energy-efficiency standards that legislate improvements in building and applianceenergy usage, changes in consumer behavior that result in greaterenergy use after initiation in a DSM program, the natural operations of the marketplace, and weather and business-cycl e adjustments. 

## Page 5 of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EEnergy Efficiency: A ratio of service provided to energy input (e.g., lumensto wattsin the case of light bulbs). Services

provided can include buildings-sector end uses such as lightin g, refrigeration, and heating: industrial processes; or vehicle transportation. Unlike conservation, which involves some redu ction of service, energy efficiency provides energy reduction s without sacrifice of service. May also refer to the use of t echnology to reduce the energy needed for a given purposeor service. Energy efficiency, Electricity: Refers to programs that are aimed at reducing the en ergy used by specific end-use devices and systems, typically without affecting the services provided. These programs reduce overall electricity consumption (reported in megawatthours), often without explicit con sideration for the timing of program-induced savings. S uch savings are generally achieved by substituting technologically more advan ced equipment to produce the same level of end-use service s (e.g. lighting, heating, motor drive) with less electr icity. Examples include high-efficiency appliances, efficientlighting programs, high-efficiency heating, ventilating and air co nditioning (HVAC) systems or control modifications, effici ent building design, advanced electric motor drives, and heat recovery syste ms. Energy efficient motors: Are also known as "high-efficiency motors" and "premium motors." They are virtually interchangeable with standard motors, but differences in construction make them more energy efficient. Energy exchange: Any transaction in which quantities of energy are recei ved or given up in return for similar energy products. See exchange, electricity ; exchange, petroleum ; and exchange, natural gas

. Energy expenditures: The money directly spent by consumers to purchase energy. E xpenditures equal the amount of energy used by the consumer multiplied by the price per un it paid by the consumer. Energy information: Includes (A) all information in whatever form on fue l reserves, extraction, and energy resources (including petrochemical feedstocks) wherever located; produ ction, distribution, and consumption of energy and fuels wherever carried on; and (B) matters relating to energ y and fuels, such as corporate structure and proprietary r elationships, costs, prices, capital investment, and assets, and other matt ers directly related there to, wherever they exist. Energy Information Administration (EIA): An independent agency within the U.S. Department ofEnergy that develops surveys, collects energy data, and does analytical and modeli ng analyses of energy issues. The Agency must satisfy the requests of Congress, other elements within the Departme nt of Energy, Federal Energy Regulatory Commission, the Executive Branch, its own independent needs, and assist the general public, or other interest groups, without takin g a policy position. Energy Intensity: A ratio of energy consumption to another metric, typica lly national gross domestic product in the case of a country's energy intensity. Sector-specific intensities may ref er to energy consumption per household, per unit of comm ercial floorspace, per dollar value industrial shipment, or ano ther metric indicative of a sector. Improvements in ener gy intensity include energy efficiency and conservation as well as structur al factors not related to technology or behavior. Energy intensity (Commercial Buildings Energy Consu mption Survey): The ratio of consumption to floor space. Energy loss: Deleted because there is no need for a general term to encompass all forms of energy loss. Terms referring to losses specific to particular energy sources are defined sepa rately. Energy loss (power): See Power loss

. Energy management and control system(EMCS): An energy conservation feature that uses mini/microcomput ers, instrumentation, control equipment, and software to ma nage a building's use of energy for heating, ventilatio n, air conditioning, lighting, and/or business-related processes. These systems can also manage fire control, safety, and securi ty. Not included as EMCS are time-clock thermostats. 

## Page 6of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EEnergy management practices: Involvement, as a part of the building's normal operations, in energy efficiency programs

that are designed to reduce the energy used by specific en d-use systems. This includes the following EMCS, DSM Progra m Participation, Energy Audit, and a Building Energy Ma nager. Energy Policy Act of 1992 (EPACT): This legislation creates a new class of power generators, exempt wholesale generators, that are exempt from the provisions of the P ublic Holding Company Act of 1935 and grants the author ity to the Federal Energy Regulatory Commission to order and condit ion access by eligible parties to the interconnected tran smission grid. Energy production: See production terms associated with specific energy types. Energy receipts: Energy brought into a site from another location. Energy reserves: Estimated quantities of energy sources that are demonst rated to exist with reasonable certainty on the basis of geologic and engineering data (proved reserves) or that can reasonably be expected to exist on the basis of geologic evidence that supports projections from proved reserves (prob able/indicated reserves). Knowledge of the location, qua ntity, and grade of probable/indicated reserves is generally inco mplete or much less certain than it is for proved energy r eserves. Note: This term is equivalent to "Demonstrated Reserves" as defined in the resource/reserve classification contained i n the U.S. Geological Survey Circular 831,1980. Demonstrated r eserves include measured and indicated reserves but exclude inferred reserves. Energy sale(s): The transfer of title to an energy commodity from a se ller to a buyer for a price or the quantity transferred during a specified period. Energy savings: A reduction in the amount of electricity used by end use rs as a result of participation in energy efficiency programs and load management programs. Energy service provider: An energy entity that provides service to a retail or en d-use customer. Energy source: Any substance or natural phenomenon that can be consum ed or transformed to supply heat or power. Examples include petroleum, coal, natural gas, nuclear, b iomass, electricity, wind, sunlight, geothermal, water mo vement, and hydrogen in fuel cells. Energy supplier: Fuel companies supplying electricity, natural gas, fuel o il, kerosene, or LPG (liquefied petroleum gas) to the household. Energy supply: Energy made available for future disposition. Supplycan be considered and measured from the point of view of the energy provider or the receiver. Energy used in the home: For electricity or natural gas, the quantity is the amo unt used by the household during the365- or 366-day period. For fuel oil, kerosene, and liquefied petroleum gas (LPG), the quantity consists of fuel purcha sed, not fuel consumed. If the level of fuel in the storage tank was th e same at the beginning and end of the annual period , then the quantity consumed would be the same as the quantity purcha sed. Energy-use sectors: A group of major energy-consuming components of U.S. so ciety developed to measure and analyze energy use. The sectors most commonly referred to in EIA ar e: residential, commercial, industrial, transportation, and electric power. Energy-weighted industrial output: The weighted sum of real output for all two-digit Standard Industrial Classification(SIC) manufacturing industries plus agriculture, construction, a nd mining. The weight for each industry is the ratio be tween the quantity of end-use energy consumption to the value of re al output. 

## Page 7 of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EEngine size: The total volume within all cylinders of an engine wh en pistons are at their lowest positions. The engine is

usually measured in "liters" or "cubic inches of displacement(CID)." Generally, larger engines result in greater e ngine power, but less fuel efficiency. There are 61.024 cubic inches in aliter. Enriched uranium: Uranium in which the U-235 isotope concentration has been increased to greater than the 0.711 percent U-235 (by weight) present in natural uranium. Enrichment feed deliveries: Uranium that is shipped under contract to a supplier o f enrichment services for use in preparing enriched uranium product to a specified U-235concentration and that ultimately will be used as fuel in a nuclear reactor. Enrichment tails assay: A measure of the amount of fissile uranium (U-235) remaining in the waste stream from the uranium enrichment process. The natural uranium "feed" that enters the enrichment process generally contains 0.711 percent (by weight) U-235. The "product stream" contains enriched uranium (more than 0.711 percentU-235) and t he "waste" or "tails" stream contains depleted uranium (less than 0 .711 percent U-235). At the historical enrichment tail s assay of 0.2 percent, the waste stream would contain 0.2 percent U-23 5. A higher enrichment tails assay requires more uranium feed (thus permitting natural uranium stockpiles to be decrea sed), while increasing the output of enriched material for the same energy expenditure. Environmental impact statement: A report that documents the information required toevaluate the environmental impact of a project. It informs decision makers and the public o f the reasonable alternatives that would avoid or minim ize adverse impacts or enhance the quality of the environment. Environmental protection agency (EPA) certification files: Computer files produced by EPA for analysis purposes. Fo r each vehicle make, model and year, the files contain the E PA test MPGs (city, highway, and 55/45 composite). These MPG's are associated with various combinations of engine and dri ve-train technologies (e.g., number of cylinders, enginesize, gasoline or diesel fuel, and automatic or manual transm ission). These files also contain information similar to t hat in the DOE/EPA Gas Mileage Guide, although the MPGs in that publication are adjusted for shortfall. Environmental restoration: Although usually described as "cleanup," this function e ncompasses a wide range of activities, such as stabilizing contaminated soil; treating groundwate r; decommissioning process buildings, nuclear reactors, chemi cal separations plants, and many other facilities; and exhumin g sludge and buried drums of waste. Environmental restrictions: In reference to coal accessibility, land-use restrictions th at constrain, postpone, or prohibit mining in order to protect environmental resources of an area; for example, surface- or ground water quality, a ir quality affected by mining, or plants or animals or their habit ats. EOR: Enhanced Oil Recovery EPA: Environmental Protection Agency EPA certification: A permanent label on fireplace inserts and freestandi ng wood stoves manufactured after July1, 1988, indicating that the equipment meets EPA standards for cl ean burning. EPA composite MPG: The harmonic mean of the EPA city and highway MPG (mi les per gallon), weighted under the assumption of 55 percent city driving and 45 percent highway driving. EPACT: Energy Policy Act of 1992 Equilibrium cycle: An analytical term that refers to fuel cycles that occur after the initial one or two cycles of a reactor's operation. For a given type of reactor, equilibrium cycl es have similar fuel characteristics. 

## Page 8 of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EEquity (financial): Ownership of shareholders in a corporation represented by stock.

Equity capital: The sum of capital from retained earnings and the issu ance of stock. Equity crude oil: The proportion of production that a concession owner h as the legal and contractual right to retain. Equity in earnings of unconsolidated affiliates: A company's proportional share (based on ownership) of the net earnings or losses of an unconsolidated affiliate. Establishment: An economic unit, generally, at a single physical locatio n where business is conducted or where services or industrial operations are performed. However, "establish ment" is not synonymous with "building." Estimated additional resources (EAR): The uranium in addition to reasonable assured resources (RAR) that is expected to occur, mostly on the basis of direct geological evidence, in extensions of well-explored deposits, little-explored deposits, and undiscovered deposits believed to exist along a well-de fined geologic trend with known deposits, such that the uranium can subsequently be recovered within the given cost ranges. E stimates of tonnage and grade are based on available sampling data and on knowledge of the deposit character istics as determined in the best known parts of the depo sit or in similar deposits. EAR correspond to DOE's Probable Potent ial Resource Category. ETBE: ethyl tertiary butyl ether ETBE (ethyl tertiary butyl ether): (CH 3 ) 3 COC 2 H: An oxygenate blend stock formed by the catalytic etherifi cation of isobutylene with ethanol. Ethane (C 2 H 6): A normally gaseous straight-chain hydrocarbon. It is a col orless paraffinic gas that boils at a temperature of -127.48 degrees Fahrenheit. It is extracted from natura l gas and refinery gas streams. Ethanol (C 2 H 5 OH): A clear, colorless, flammable alcohol. Ethanol is typica lly produced biologically from biomass feedstocks such as agricultural crops and cellulosic residues from agricul tural crops or wood. Ethanol can also be produced chemica lly from ethylene. See Biomass , Fuel Ethanol , and Fuel Ethanol Minus Denaturant

. Ether: A generic term applied to a group of organic chemical compounds composed of carbon, hydrogen, and oxygen, characterized by an oxygen atom attached to two carbon atom s (e.g., methyl tertiary butyl ether). Ethylene: An olefinic hydrocarbon recovered from refinery processes or petrochemical processes. Ethylene is used as a petrochemical feedstock for numerous chemical applications an d the production of consumer goods. Ethylene dichloride: A colorless, oily liquid used as a solvent and fumigant f or organic synthesis, and for ore flotation. EU: European Union Eurasia: The physical land mass containing the continents of Euro pe and Asia. For Energy Information Administration reporting, it includes the former parts of the Union of Soviet Socialist Republics (U.S.S.R) : Armenia, Azerbaijan, Belarus, Estonia, Georgia, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Moldova, Russia, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan. Evacuated-tube collector: A collector in which solar thermal heat is captured by u se of a collector fluid that flows through an absorber tube contained inside an evacuated glass tube. Evaporation pond: A containment pond (that preferably has an impermeab le lining of clay or synthetic material such as hypalon) to hold liquid wastes and to concentrate the wa ste through evaporation. 

## Page 9of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EEvaporative cooler (swamp cooler): An air-cooling unit that turns air into moist, cool a ir by saturating the air with water

vapor. It does not cool air by use of a refrigeration un it. EWG: Exempt Wholesale Generator Excess statutory depletion: The excess of estimated statutory depletion allowable as an income tax deduction over the amount of cost depletion otherwise allowable as a tax de duction, determined on a total enterprise basis. Exchange: See energy exchange

. Exchange agreement: A contractual agreement in which quantities of crude o il, petroleum products, natural gas, or electricity are delivered, either directly or through int ermediaries, from one company to another company, in excha nge for the delivery by the second company to the first company of an eq uivalent volume or heat content. The exchange may take pla ce at the same time and location or at different times an d/or locations. Such agreements may also involve the paymentof cash. Note: EIA excludes volumes sold through exchange agreements to avoid double counting of data. See energy exchange

. Exchange energy: See exchange, electricity

. Exchange, electricity: A type of energy exchange in which one electric utility agrees to supply electricity to another. Electricity received is returned in kind at a later time o r is accumulated as an energy balance until the end of a specified period, after which settlement may be made by monetary p ayment. Note: This term is also referred to as exchange energy. Exchange, natural gas: A type of energy exchange in which one company agrees todeliver gas, either directly or through intermediaries, to another company at one location or i n one time period in exchange for the delivery by the seco nd company to the first company of an equivalent volume or heat con tent at a different location or time period. Note: S uch agreements may or may not include the payment of fees in dollar or volumetric amounts. Exchange, petroleum: A type of energy exchange in which quantities of crude oil or any petroleum product(s) are received or given up in return for other crude oil or petroleu m products. It includes reciprocal sales and purchases. Exchange, power: Delete in favor of the already-defined term exchange energy, which should be renamed exchange electricity or exchange, electricity. Exempt wholesale generator (EWG): Wholesale generators created under the 1992 Energy Po licy Act that are exempt from certain financial and legal restrictions stipulated in the Public Utilities Holding Company Act of 1935. Exhaust fan: Small fans located in the wall or ceiling that exhaustair, odors, and moisture from the bathroom, kitchen, o r basement to the outside. Expenditure: The incurrence of a liability to obtain an asset or service. Expenditures per million Btu: The aggregate ratio of a group of buildings' total expenditures for a given fuel to the total consumption of that fuel. Expenditures per square foot: The aggregate ration of a group of buildings' tota l expenditures for a given fuel to the total floor space in those buildings. Exploration drilling: Drilling done in search of new mineral deposits, on e xtensions of known ore deposits, or at the location of a discovery up to the time when the company decides thatsufficient ore reserves are present to justify commercial exploration. Assessment drilling is reported as exploration drilling. 

## Page 10of 11 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=EExploratory well: A hole drilled a) to find and produce oil or gas in an area previously considered unproductive area; b) to

find a new reservoir in a known field, i.e., one previo usly producing oil and gas from another reservoir, or c) to extend the limit of a known oil or gas reservoir. Exports: Shipments of goods from within the 50 States and theDistrict of Columbia to U.S. possessions and territories o r to foreign countries. Extensions: Any new reserves credited to a previously producing reservoi r because of enlargement of its proved area. This enlargement in proved area is usually due to new well d rilling outside of the previously known productive limits o f the reservoir. Extensions, discoveries, and other additions: Additions to an enterprise's proved reserves that result from(1) extension of the proved acreage of previously discovered (old) reserves through additional drilling in periods subsequent to d iscovery and (2) discovery of new fields with proved reserves or of n ew reservoirs of proved reserves in old fields. Externalities: Benefits or costs, generated as a byproduct of an econom ic activity, that do not accrue to the parties involved in the activity. Environmental externalities are benefits or costs that manifest themselves through changes in the physi cal or biological environment. Extraction loss: The reduction in volume of natural gas due to the re moval of natural gas liquid constituents such as ethane, propane, and butane at natural gas processing p lants. Extractive industries: Industries involved in the activities of (1) prospecting a nd exploring for wasting (non-regenerative) natural resources, (2) acquiring them, (3) further explo ring them, (4) developing them, and (5) producing (ext racting) them from the earth. The term does not encompass the industri es of forestry, fishing, agriculture, animal husbandry, or any others that might be involved with resources of a regenerative nature. Extraordinary income deductions (electric utility): Those items related to transactions of a nonrecurring n ature that are not typical or customary business activities of the utility an d that would significantly distort the current year's net income if reported other than as extraordinary items. 

# A B C D E F G H I J K L M N O P Q R S T U V W XYZ Page 11 of 11 Glossary

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6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=E

# Glossary A B C D E F G H I J K L M N O P Q R S T U V W XYZ Search glossary terms: 

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

### N
N 2 O: Nitrous Oxide NAAQS: National Ambient Air Quality Standards NAICS (North American Industry Classification Syste m): A coding system developed jointly by the United States, Canada, and Mexico to classify businesses and industries accordin g to the type of economic activity in which they are engaged. NAICS replaces the Standard Industrial Classifi cation (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 o ther manufacturer supplied data. Name plate capacity: See Generator name plate capacity (installed)

. Naphtha: A generic term applied to a petroleum fraction with an approximate boiling range between 122 degrees Fah renheit 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 percent distillation temperatures of 290 degrees to 47 0 degrees Fahrenheit, and meeting Military Specificatio n MIL-T-5624L (Grade JP-4).It is used primarily for military turbojet and turboprop aircraft engines because it has a lower fr eeze point than other aviation fuels and meets engine requirements at h igh altitudes and speeds. Note: Beginning with January 2 004 data, naphtha-type jet fuel is included in Miscellaneous Products

. Naphthas: Refined or partly refined light distillates with an approximate boiling point range of 27 degrees to 221 degrees Centigrade. Blended further or mixed with other mate rials, they make high-grade motor gasoline or jet fuel. Also, used as solvents, petrochemical feedstocks, or as raw materials for th e production of town gas. NARUC: See National Association of Regulatory Utility Commissioners

. National Association of Regulatory Utility Commissi oners (NARUC): An affiliation of the public service commissioners to promote the uniform treatment of members of the r ailroad, public utilities, and public service commissions o f the 50 states, the District of Columbia, the Commonwealth of PuertoRico, and the territory of the Virgin Islands. 

## Page 1 of 9 Glossary

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6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNational Defense Authorization Act: The federal law, enacted in 1994 and amended in 19 95, 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 re medial action under the Comprehensive Environmental Resp onse, Compensation, and Liability Act (CERCLA). The list is ba sed primarily on the score a site receives from the Environm ental 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 (NR ECA): A national organization dedicated to representing th e interests of cooperative electric utilities and the consumer s 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 reso urces and continued through1983 by the AEC's successor agencies, the Energy Research and Development Administrat ion (ERDA), and the Department of Energy (DOE).The NURE program included aerial radiometric and magnetic surveys, hydrogeochemical and stream sediment surveys, geologic drill ing in selected areas, geophysical logging of selected bore hol es, and geologic studies to identify and evaluate geologi c 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 ob ligated to serve. NERC definition Natural gas: A gaseous mixture of hydrocarbon compounds, the primary o ne being methane

. Natural gas field facility: A field facility designed to process natural gas produce d from more than one lease for the purpose of recovering condensate from a stream of natural gas; however, some field facilities are designed to reco ver propane, normal butane, pentanes plus, etc., and to co ntrol the quality of natural gas to be marketed. Natural gas gross withdrawals: Full well-stream volume of produced natural gas, exclud ing condensate separated at the lease. Natural gas hydrates: Solid, crystalline, wax-like substances composed of water, m ethane, and usually a small amount of other gases, with the gases being trapped in the interst ices of a water-ice lattice. They form beneath permafro st 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 in jected 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): Those hydrocarbons in natural gas that are separated fr om the gas as liquids through the process of absorption, condensation, adsorption, cooling i n gas separators, gas processing, or gas cycling plants. Gener ally, natural gas liquids include natural gas plant liquidsand lease condensate

. Natural gas liquids production: The volume of natural gas liquids removed from natura l gas in lease separators, field facilities, gas processing plants, or cycling plants during th e report year. Natural gas marketed production: Gross withdrawals of natural gas from production reservo irs, less gas used for reservoir repressuring, nonhydrocarbon gases removed in treating an d processing operations, and quantities vented and flared

. 

## Page 2of 9 Glossary

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6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNatural gas marketer: A company that arranges purchases and sales of natural ga s. Unlike pipeline companies or local

distribution companies, a marketer does not own physical asse ts commonly used in the supply of natural gas, such as pipelines or storage fields. A marketer may be an affili ate of another company, such as a local distribution compan y, natural gas pipeline, or producer, but it operates independent ly of other segments of the company. In States with reside ntial choice programs, marketers serve as alternative suppliers to residen tial users of natural gas, which is delivered by a local distribution company. Natural gas plant liquids: Those hydrocarbons in natural gas that are separated as liquids at natural gas processing plants, fractionating and cycling plants, and in some insta nces, field facilities. Lease condensate is excluded. Products obtained include liquefied petroleum gases (ethane, propane, and butanes), pentanes plus, and isopentane. Com ponent products may be fractionated or mixed. 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 quali ty of the natural gas to be marketed. Cycling plants are classified a s gas processing plants. Natural gas production: See Dry natural gas production

. Natural gas utility demand-side management (DSM) pr ogram sponsor: A DSM (demand-side management) program sponsored by a natural gas utility that suggests ways to incre ase the energy efficiency of buildings, to reduce energy cost s, 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 term used in the gas processing industry to refer to amixture of liquid hydrocarbons (mostly pentanes and heavier hydrocarbons) extracted from natural gas. It i ncludes isopentane. Natural Gasoline and Isopentane: A mixture of hydrocarbons, mostly pentanes and heavier, e xtracted from natural gas, that meets vapor pressure, end-point, and other specifications for natural gasoline set by the Gas Processors Associatio n. Includes isopentane which is a saturated branch-chain hydro carbon, (C 5 H 12 ), obtained by fractionation of natural gasoline or isomerization of normal pentane. Natural reservoir pressure: The energy within an oil or gas reservoir that causes th e 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 re sult of "dissolved gas drive," "gas cap drive," or "water drive." Re gardless 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 upstrea m 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 future s and options trading and other transactions, is the active contract with the shortest time to maturity. It is the contract that will expire f irst (often, but not always, within the next month). The near month is also ca lled the prompt month, the front month, the lead mo nth, and the first nearby. NERC: See North American Electric Reliability Corporation

. 

## Page 3 of 9 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNet 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 cel l purchases. Net electricity consumption: Consumption of electricity computed as generation, plus imports, minus exports, minus transmission and distribution losses. Net energy for load: Net generation of main generating units that are syst em-owned or system-operated, plus energy receipts minus energy deliveries. Net energy for load (electric): Net Balancing Authority Area generation, plus energy received from other Balancing Authority Areas, less energy delivered to Balancing Author ity Areas through interchange. It includes Balancing Aut hority Area losses but excludes energy required for storage at energy sto rage facilities. NERC definition Net energy for system: The sum of energy an electric utility needs to satisfy the ir service areas, including full and partial requirements consumers. Net generation: The amount of gross generation less the electrical ener gy consumed at the generating station(s) for station service or auxiliaries. Note: Electricity required for pump ing at pumped-storage plants is regarded as electricity fo r station service and is deducted from gross generation. Net head: The gross head minus all hydraulic losses except those charge able to the turbine. Net income: Operating income plus other income and extraordinary i ncome 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 po sitive number indicates that more electricity (including a ssociated losses) came into the state than went out of the state du ring the year; conversely, a negative number indicates that more electricity (including associated losses) went out of the stat e than came into the state. Net module shipments: Represents the difference between module shipments and module purchases. When exported, incomplete modules and unencapsulated cells are also includ ed. Net operable capacity: Total owned capacity less in operable capacity. Net photovoltaic module shipment: The difference between photovoltaic module shipments a nd 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 arr angement is considered a nonoperating interest, as distin guished from a working interest, because it does not involve the rights an d 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 tota l 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 t hrough September 30.) This output reflects a reduction in capaci ty due to electricity use for station service or auxiliaries.

## Page 4of 9 Glossary

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6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNet 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 Decembe r 1 through February 28). This output reflects a reduction i n capacity due to electricity use for station service or auxili aries. 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 th at crude as well as other considerations (e.g., transport ation and processing costs). Typically, the price is calculated based on product prices extant on or near the cargo's date of impo rtation. 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 oxidat ion of nitric oxide (NO) which is produced by the combustion of solid fuels. Nitrogen oxides (NOx ): Compounds of nitrogen and oxygen produced by the burn ing of fossil fuels. Nitrous oxide (N 2 O): A colorless gas, naturally occurring in the atmosphere. N itrous 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 eng ines generally operated under frequent speed and load chang es, 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 eith er 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 te mperatures of 400 degrees Fahrenheit at the 10-percentrecovery point and 550 degrees Fahrenheit at the 90-percent re covery 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. Se e No. 1 Distillate

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

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

## Page 5 of 9 Glossary

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6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNo. 2 fuel oil (heating oil): 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 396. It is used in atomizing type burners for domestic heating or for moderate capacity commercial/indust rial burner units. See No. 2 Distillate

. No. 2 fuel oil and No. 2 diesel sold to consumers f or all other end uses: Those consumers who purchase fuel oil or diesel fuel for their own use including commercial/instit utional buildings (including apartment buildings), man ufacturing and nonmanufacturing establishments, farms (including farm h ouses), motor vehicles, commercial or private boats, military, governments, electric utilities, railroads, construction, lo gging 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 t he specific purpose of heating their home, water heating, cooking, etc., excluding farm houses, farming and apartment buil dings. No. 4 fuel oil: A distillate fuel oil made by blending distillate f uel oil and residual fuel oil stocks. It conforms with AST M Specification D 396 or Federal Specification VV-F-815C and is used extensively in industrial plants and in commerci al burner installations that are not equipped with preheating f acilities. It also includes No. 4 diesel fuel used for low - and medium-speed diesel engines and conforms to ASTM Specification D 975. No. 5 and no. 6 fuel oil sold directly to the ultim ate consumer: Includes ships, mines, smelters, manufacturing plants, electric utilities, drilling, railroad. No. 5 and no. 6 fuel oil sold to refiners or other dealers who will resale the product: Includes all volumes of No. 5 and No. 6 fuel oil purchased by a trade or business with the intent of reselling the product to the ultimate consume rs. No x : See Nitrogen oxides
NOAA: National Oceanic and Atmospheric Administration. NOAA division: One of the 345 weather divisions designated by the Nat ional 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 fo llow county borders when weather conditions vary considerabl y within a county; such is likely to happen when the county b orders the ocean or contains high mountains. A state conta ins 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 oper ating under demand. Nominal dollars: A measure used to express nominal price. Nominal price: The price paid for a product or service at the time ofthe transaction. Nominal prices are those that have not been adjusted to remove the effect of changes in the pu rchasing 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 byproductor a discarded product. "Non-biomass waste" includes municipal solid waste from non-biogenic sources, such as plastics, and tire-derived fuels. Nonassociated natural gas: Natural gas that is not in contact with significant qua ntities 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 desi gnated pollutants, such as carbon monoxide and ozone. Nonbranded product: Any refined petroleum product that is not a branded product. 

## Page 6of 9 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNoncoincident demand: Sum of two or more demands on individual systems that d o not occur in the same demand

interval. Noncoincidental peak load: The sum of two or more peak loads on individual systems t hat 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, aheating or cooling season, and usually for not more than 1 year. Nonconventional plant (uranium): A facility engineered and built principally for pro cessing of uraniferous solutions that are produced during in situ leach mining, from heap leachi ng, or in the manufacture of other commodities, and th e 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 alternati ve fuel and /or on either gasoline or diesel. Nonfirm power: Power or power-producing capacity supplied or availableunder a commitment having limited or no assured availability. Nonfuel components: Components that are not associated with a particular f uel. These include, but are not limited to, control spiders, burnable poison rod assemblies, control ro d 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 vi a existing petroleum product distribution systems because of incompatibility problems. Gasoline/ethano l blends, for example, are contaminated by water that i s typically present in petroleum product distribution systems. Nonhydrocarbon gases: Typical nonhydrocarbon gases that may be present in rese rvoir natural gas, such as carbondioxide, helium, hydrogen sulfide, and nitrogen. Nonmethane volatile organic compounds (NMVOC): Organic compounds, other than methane, that particip ate 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 bee n identified, but which did not produce during the report year to the owned or contracted inte rest of the reporting company regardless of the availabil ity 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 requi rements 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 residenti al. Nonresidential buildings comprise three groups commercial, manufacturing/industrial, and agricu ltural. Nonroad alternative fuel vehicle (nonroad AFV): An alternative fuel vehicle designed for off-road ope ration and use for surface/air transportation, industrial, or commercial pur poses. Nonroad AFVs include forklifts and other industrial vehicles, rail locomotives, self-propelled electric rail cars, aircraft, airport service vehicles, construction vehicles, agricultura l vehicles, and marine vessels. Recreational AFVs (golf carts, snow mob iles, pleasure watercraft, etc.) are excluded from the de finition. 

## Page 7 of 9 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNonspinning reserve: The generating capacity not currently running but capab le of being connected to the bus and load

within a specified time. Nonutility generation: Electric generation by end-users, or small power produce rs under the Public Utility Regulatory Policies Act, to supply electric power for industrial, comme rcial, andmilitary operations, or sales to electric util ities. Nonutility power producer: A corporation, person, agency, authority, or other le gal entity or instrumentality that owns or operates facilities for electric generation and is not a n electric utility. Nonutility power producers include qu alifying cogenerators, qualifying small power producers, and othe r nonutility generators (including independent power producers). Non-utility power producers are without a designated f ranchised service area and do not file forms listed in theCode of Federal Regulations, Title 18, Part 141 NOPR: Notice of Proposed Rulemaking Normal butane (C 4 H 10 ): A normally gaseous straight chain hydrocarbon that is a co lorless paraffinic gas which boils at a temperature of 31.1 degrees Fahrenheit. North American Electric Reliability Corporation (NE RC): A nonprofit corporation formed in 2006 as the succes sor to the North American Electric Reliability Council established todevelop and maintain mandatory reliability standards for the bulk electric system, with the fundamental goal of maintaini ng and improving the reliability of that system. NERC con sists 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 (NAIC S): A new classification scheme, developed by the Office of Management and Budget to replace the Standard Indust rial Classification (SIC) System, that categorizes establishm ents according to the types of production processes they primarilyuse. NRECA: See National Rural Electric Cooperative Association Nuclear electric power (nuclear power): Electricity generated by the use of the thermal energ y released from the fission of nuclear fuel in a reactor. Nuclear fuel: Fissionable materials that have been enriched to such acomposition that, when placed in a nuclear reactor, will support a self-sustaining fission chain reaction, prod ucing 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 materia l), moderating material to control the rate of fission , a heavy-walled pressure vessel to house reactor components, shielding to pro tect personnel, a system to conduct heat away from the reactor, and instrumentation for monitoring and contro lling 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 minin g coal across two counties within a State, or across two St ates, then it is counted as two operations. This is done so that EIA can sep arate 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 m ine and preparation plant, or a preparation plant o nly, will be counted as two operations if the preparation plant processes both underground and surface coal. Excluded are silt, culm, re fuse bank, slurry dam, and dredge operations except for Pennsylvania a nthracite. Excludes mines producing less than 10,000 short tons of coal during the year. 

## Page 8 of 9 Glossary

- U.S. Energy Information Administration (EIA)

6/25/2012 http://www.eia.gov/tools/glossary/index.cfm?id=NNURE: See National Uranium Resource Evaluation

NYMEX: New York Mercantile Exchange 

# A B C D E F G H I J K L M N O P Q R S T U V W XYZ Page 9of 9 Glossary

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