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Glossary of Energy Terms "E"


E-10 Unleaded: Unleaded gasoline enhanced with ethanol, which is blended at a rate of ten percent.

E85: A fuel containing a mixture of 85 percent ethanol and 15 percent gasoline.

East Region: In alignment with the American Gas Association definition, the Energy Information Administration adopted three natural gas storage regions: the East Region, the West Region, and the Producing Region. The East Region includes the following states: Connecticut, Delaware, District of Columbia, Florida, Georgia, Iowa, Illinois, Indiana, Kentucky, Massachusetts, Maryland, Maine, Michigan, Missouri, North Carolina, Nebraska, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, Wisconsin, and West Virginia. Also see map.

Ecology: The study of interrelationships of animals and plants to one another and to their environment.

Economic Efficiency: A term that refers to the optimal production and consumption of goods and services. This generally occurs when prices of products and services reflect their marginal costs. Economic efficiency gains can be achieved through cost reduction, but it is better to think of the concept as actions that promote an increase in overall net value (which includes, but is not limited to, cost reductions).

Economic Energy Intensity: The amount of energy consumed to create one dollar of Gross State Product.

Economies of Scale: Economies of scale exist where he industry exhibits decreasing average long-run costs with size.

Economizer Air: A ducting arrangement and automatic control system that allows a heating, ventilation and air conditioning (HVAC) system to supply up to 100 percent outside air to satisfy cooling demands, even if additional mechanical cooling is required.

Economizer Water: A system which uses either direct evaporative cooling, or a secondary evaporatively cooled water loop and cooling coil to satisfy cooling loads, even if additional mechanical cooling is required.

Ecosystem: The interacting system of biological community and its nonliving environment.

Edison Electric Institute (EEI): An association of electric companies formed in 1933 "to exchange information on industry developments and to act as an advocate for utilities on subjects of national interest."

Edison, Thomas Alva: The "father" of the American energy industry, Thomas Edison was an American inventor who was born in 1847 and died in 1931. He patented a total of 1,093 inventions: more than any other person in American history. Among the most important were the incandescent electric light bulb (1879), the phonograph (1877) and the movie projector (1893).

Efficacy, Lighting: The ratio of light from a lamp to the electrical power consumed, including ballast losses, expressed as lumens per watt.

Efficiency: The ratio of the useful energy delivered by a dynamic system (such as a machine, engine or motor) to the energy supplied to it over the same period or cycle of operation. The ratio is usually determined under specific test conditions.

Electric Generator: 1) A device that converts a heat, chemical or mechanical energy into electricity. 2) A facility that produces only electricity, commonly expressed in kilowatthours (kWh) or megawatthours (MWh). Electric generators include electric utilities and independent power producers

Electric Power Sector (formerly called the Electric Utility Sector): Privately and publicly owned facilities for the generation, transmission, distribution or sale of electric energy. Electric power sector is also a category in the report Nebraska's Total Energy Expenditures by Fuel Type and by End-Use Sector. In this report, electric power sector was formerly called electric utility fuel, which refers to the energy input at electric utilities. It is measured in physical units (barrels, short tons, cubic feet, et al.) as the consumption of fossil fuels and as net generation (kilowatthours) from nuclear, solar, wind, geothermal, wood and waste energy sources. In the case of prices and expenditures, it represents the average price paid and the total expenditures by electric utilities for fuels.

Electric Radiant Heating: A heating system in which electric resistance is used to produce heat which radiates to nearby surfaces. There is no fan component to a radiant heating system.

Electric Resistance Heater: A device that produces heat through electric resistance. For example, an electric current is run through a wire coil with a relatively high electric resistance, thereby converting the electric energy into heat which can be transferred to the space by fans.

Electric Utility: Any person or state agency with a monopoly franchise (including any municipality), which sells electric energy to end-use customers; this term includes the Tennessee valley Authority, but does not include other Federal power marketing agencies such as Western Area Power Administration.

Electric Utility Fuel: Energy input at electric utilities. It is measured in physical units (barrels, short tons, cubic feet, et al.) as the consumption of fossil fuels and as net generation (kilowatthours) from nuclear, solar, wind, geothermal, wood and waste energy sources. In the case of prices and expenditures, it represents the average price paid and the total expenditures by electric utilities for fuels. Also see Electric Power Sector.

Electric Vehicle (EV): A vehicle powered by electricity, usually provided by batteries but may also be provided by photovoltaic (solar) cells or a fuel cell.

Electrical System Energy Losses: The amount of energy lost during generation, transmission and distribution of electricity (including electricity used by the generating plant).

Electricity: A property of the basic particles of matter. A form of energy having magnetic, radiant and chemical effects. Electric current is created by a flow of charged particles (electrons).

Electricity (formerly called Electric Utility Sales): A category in the report "Nebraska's Total Energy Consumption by Fuel Type and by End-Use Sector". The amount of Btu sold in a given period of time; usually grouped by classes of service, such as residential, commercial, industrial, and transportation.

Electricity Consumers Resources Council (ELCON): ELCON is an association of 28 large industrial consumers of electricity. ELCON members account for over five percent of all electricity consumed in the United States. ELCON was formed in 1976 "to enable member companies to "work cooperatively for the development of coordinated, rational and consistent policies affecting electric energy supply and pricing at the federal, state, and local levels."

Electricity Exports: Electricity exports are electricity transmitted across U.S. borders to Canada and Mexico. The annual U.S. total imports and exports quantities and revenue are used to calculate U.S. annual average prices which are assigned to each of the states with electricity trade. In the case of expenditures, state-level aggregations of the revenue data are not available.

Electricity Imports: Electricity imports are electricity transmitted across U.S. borders from Canada and Mexico. The annual U.S. total imports and exports quantities and revenue are used to calculate U.S. annual average prices which are assigned to each of the states with electricity trade. In the case of expenditures, state-level aggregations of the revenue data are not available.

Electricity Net Imports: Electricity exports are subtracted from imports to derive electricity net imports.

Electricity Purchased by End-Users: Electricity sold by the electric utilities to customers in the residential, commercial, industrial, and transportation sectors. In the case of prices and expenditures, it is the average price paid for electricity or the total esxpenditures for electricity by those consuming sectors. Also called electricity sales.

Electrolysis: Breaking a chemical compound down into its elements by passing a direct current through it. Electrolysis of water, for example, produces hydrogen and oxygen.

Electromagnetic Fields (EMF): Ordinary every day use of electricity produces magnetic and electric fields. These 60 Hertz fields (fields that go back and forth 60 times a second) are associated with electrical appliances, power lines and wiring in buildings.

Element: A substance consisting entirely of atoms of the same atomic number.

Elevation: 1) The height above sea level (altitude); 2) A geometrical projection, such as a building, on a plane perpendicular to the horizon.

Emergency Core Cooling System (ECCS): Equipment designed to cool the core of a nuclear reactor in the event of a complete loss of the coolant.

Emission Standard: The maximum amount of a pollutant legally permitted to be discharged from a single source.

Emissions: Releases of greenhouse gases into the atmosphere that are caused by human activity (e.g., the release of carbon dioxide during fuel combustion).

Emissivity: The property of emitting radiation; possessed by all materials to a varying extent.

Emittance: The emissivity of a material, expressed as a fraction. Emittance values range from 0.05 for brightly polished metals to 0.96 for flat black paint.

End-Use Energy: A measure of the energy content of fuels at the point where they are consumed. End-use energy does not include energy lost during the generation and transmission of electricity.

End-Use Energy Consumption: The sum of fossil fuel consumption by the four end-use sectors plus electric utility sales to those sectors and generation of hydroelectric power by nonelectric Utilities.

End-Use Sectors: The residential, commercial, industrial and transportation sectors of the economy.

Energy: The capacity for doing work. Forms of energy include: thermal, mechanical, electrical and chemical. Energy may be transformed from one form into another.

Energy Charge: The amount of money owed by an electric customer for kilowatt-hours consumed.

Energy Conservation: Activities that reduce end-use demand for energy by reducing the service demanded.

Energy Consumption: The amount of energy consumed in the form in which it is acquired by the user. The term excludes electrical generation and distribution losses.

Energy Efficiency: Energy efficiency means doing the same work, or more, and enjoying the same comfort level with less energy. Programs designed to use energy more efficiently: doing the same with less. Energy efficiency is distinguished from Demand Side Management programs in that the latter are utility-sponsored and -financed, while the former is a broader term not limited to any particular sponsor or funding source. "Energy conservation" is a term which has also been used but it has the connotation of doing without in order to save energy rather than using less energy to do the same thing and so is not used as much today. Energy conservation is rooted in behavior while energy efficiency is technology-based. Many people use these terms interchangeably.

Energy Efficiency Ratio (EER): The ratio of cooling capacity of an air conditioning unit in British thermal units per hour to the total electrical input in watts under specified test conditions.

Energy/Fuel Diversity: Policy that encourages the development of energy technologies to diversify energy supply sources, thus reducing reliance on conventional (petroleum) fuels; applies to all energy sectors.

Energy Information Administration (EIA): The independent statistical and analytical agency within the U.S. Department of Energy.

Energy Intensity: The ratio of energy input per unit of economic output, which measures the increasing energy efficiency of the economy.

Energy Management System: A control system (often computerized) designed to regulate the energy consumption of a building by controlling the operation of energy consuming systems, such as the heating, ventilation and air conditioning (HVAC), lighting and water heating systems.

Energy Policy Act (EPAct): The Energy Policy Act of 1992 addresses a wide variety of energy issues. The legislation creates a new class of power generators, exempt wholesale generators (EWGs), that are exempt from the provisions of the Public Utilities Holding Company Act of 1935 and grants the authority to the Federal Energy Regulatory Commission to order and condition access by eligible parties to the interconnected transmission grid.

Energy Reserves: The portion of total energy resources that is known and can be recovered with presently available technology at an affordable cost.

Energy Resources: Everything that could be used by society as a source of energy.

Energy Security/Fuel Security: Policy that considers the risk of dependence on fuel sources located in remote and unstable regions of the world and the benefits of domestic and diverse fuel sources.

Energy Service Company (ESCO): A company that offers to reduce a client's electricity consumption with the cost savings being split with the client. May also be called an Efficiency Services Company.

Energy Source: The primary source that provides the power that is converted to electricity through chemical, mechanical or other means.

Enthalpy: The quantity of heat necessary to raise the temperature of a substance from one point to a higher temperature. The quantity of heat includes both latent and sensible.

Entitlement: Electric energy or generating capacity that a utility has a right to access under power exchange or sales agreements.

Environmental Protection Agency (EPA): A federal agency created in 1970 to permit coordinated governmental action for protection of the environment by systematic abatement and control of pollution through integration or research, monitoring, standards setting and enforcement activities.

Ethane: A normally gaseous straight-chain hydrocarbon. It is a colorless, paraffinic gas that boils at a temperature of -127.48 degrees Fahrenheit. It is extracted from natural gas and refinery gas streams.

Ethanol (also know as Ethyl Alcohol or Grain Alcohol, CH3CH2OH): A liquid that is produced chemically from ethylene or biologically from the fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood. Used in the United States as a gasoline octane enhancer and oxygenate, it increases octane 2.5 to 3.0 numbers at 10 percent concentration. Ethanol can also be used in higher concentration (E85) in vehicles optimized for its use.

Ethanol-Blended Fuel: A fuel mixture that is a concentration of ethanol blended with gasoline.

Ethylene: A colorless gas that burns and is an oil refinery product.

Ethyl Tertiary Butyl Ether (ETBE): An aliphatic ether similar to MTBE):. This fuel oxygenate is manufactured by reacting isobutylene with ethanol. Having high octane and low volatility characteristics, ETBE can be added to gasoline up to a level of approximately 17 percent by volume. ETBE is used as an oxygenate in some reformulated gasolines.

Evaporative Cooling: Cooling by exchange of latent heat from water sprays, jets of water, or wetted material.

Exempt Wholesale Generator (EWG): Created under the 1992 Energy Policy Act, these wholesale generators are exempt from certain financial and legal restrictions stipulated in the Public Utilities Holding Company Act of 1935.

Exfiltration: Air flow outward through a wall, building envelope or similar structure.

Exhaust: Air removed deliberately from a space, by a fan or other means, usually to remove contaminants from a location near their source.

Exploratory Well: A well drilled to find and produce oil or gas in an unproven area, to find a new reservoir in a field previously found to be productive or to extend the limit of a known reservoir.

Exports (Electric Utility): Power capacity or energy that a utility is required by contract to supply outside of its own service area and not covered by general rate schedules.

Extra High Voltage (EHV): Voltage levels higher than those normally used on transmission lines. Generally EHV is considered to be 345,000 volts or higher.