Glossary of Energy Terms

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A B C D E F G H I J K L M N O P Q R S T U V W X-Z Acronyms

Note: No entries for Y or Z.

Letter E

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).

ECONOMIES OF SALE - Economies of scale exist where the 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.

ECONOMY ENERGY (Electricity utility) - Electricity purchased by one utility from another to take the place of electricity that would have cost more to produce on the utility's own system.

ECOSYSTEM - The interacting system of biological community and its nonliving environment.

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).

EEI - Edison Electric Institute. 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."

EER - (Energy Efficiency Ratio) the ratio of cooling capacity of an air conditioning unit in Btus per hour to the total electrical input in watts under specified test conditions. California Code of Regulations, Section 1602(c)(6).

EFFICACY, LIGHTING - The ratio of light from a lamp to the electrical power consumed, including ballast losses, expressed as lumens per watt. [See California Code of Regulations, Title 24, Section 2-5302]

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.

ELCON - Electricity Consumers Resources Council. 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."

ELECTRIC GENERATOR - A device that converts a heat, chemical or mechanical energy into electricity.

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 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 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 agency (from EPAct).

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).

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.

EMBEDDED COSTS EXCEEDING MARKET PRICES (ECEMP) - Embedded costs of utility investments exceeding market prices are: i) costs incurred pursuant to a regulatory or contractual obligation; 2) costs that are reflected in cost-based rates; and 3) cost-based rates that exceed the price of alternatives in the marketplace. ECEMPS may become "stranded costs" where they exceed the amount that can be recovered through the asset's sale. Regulatory questions involve whether such costs should be recovered by utility shareholders and if so, how they should be recovered. "Transition costs" are stranded costs which are charged to utility customers through some type of fee or surcharge after the assets are sold or separated from the vertically-integrated utility. "Stranded assets" are assets which cannot be sold for some reason. The British nuclear plants are an example of stranded assets which no one would buy. (Also referred to as Transition Costs.)

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.

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.

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 BUDGET - A requirement in the Building Energy Efficiency Standards that a proposed building be designed to consume no more than a specified number of British thermal units (Btus) per year per square foot of conditioned floor area.

ENERGY CHARGE - The amount of money owed by an electric customer for kilowatt-hours consumed.

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 - Using less energy/electricity to perform the same function. Programs designed to use electricity more efficiently - doing the same with less. For the purpose of this paper, energy efficiency is distinguished from DSM 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 some thing and so is not used as much today. Many people use these terms interchangeably.


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 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 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 RESOURCES PROGRAM ACCOUNT (ERPA) - The state law that directs California electric utility companies to gather a state energy surcharge per kilowatt hour of electricity consumed by a customer. These funds are used for operation of the California Energy Commission. As of January 1, 2004, the surcharge is set at of three-tenths of one mil ($0.0003) per kilowatt-hour

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.

ENHANCED GREENHOUSE EFFECT - The natural greenhouse effect has been enhanced by anthropogenic emissions of greenhouse gases. Increased concentrations of carbon dioxide, methane, and nitrous oxide, CFCs, HFCs, PFCs, SF6, NF3, and other photochemically important gases caused by human activities such as fossil fuel consumption and adding waste to landfills, trap more infra-red radiation, thereby exerting a warming influence on the climate. See Climate Change and Global Warming. (EPA)

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.

EPA - The Environmental Protection Agency. A federal agency charged with protecting the environment.

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 FERC to order and condition access by eligible parties to the interconnected transmission grid.

ESCO - Efficiency Service Company - A company that offers to reduce a client's electricity consumption with the cost savings being split with the client.

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.

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.

ETHYLENE - A colorless gas that burns and is an oil refinery product.

EV (ELECTRIC VEHICLE) - a vehicle powered by electricity, usually provided by batteries but may also be provided by photovoltaic (solar) cells or a fuel cell.

EVAPORATIVE COOLING - Cooling by exchange of latent heat from water sprays, jets of water, or wetted material.

EXCEPTIONAL METHOD - An approved alternative calculation method that analyzes designs, materials, or devices that cannot be adequately modeled using public domain computer programs. Exceptional methods must be submitted to and approved by the California Energy Commission. [See California Code of Regulations, Title 20, Section 1409(b)3] Two examples of exceptional methods are the controlled ventilation crawl space (CVC) credit and the combined hydronic space and water heating method.

EXCHANGE (Electric utility) - Agreements between utilities providing for purchase, sale and trading of power. Usually relates to capacity (kilowatts) but sometimes energy (kilowatt-hours).

EXECUTIVE ORDER NUMBER 6 - A provision under the California Emergency Services Act permits the Governor to establish, by Executive Order Number 6, a state Petroleum Fuels Set-Aside Program after proclamation of an energy emergency.

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, etc.

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

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.

A B C D E F G H I J K L M N O P Q R S T U V W X-Z Acronyms

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