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nameplate rating
The full-load electrical quantities assigned by the designer to a generator and its prime mover or other piece of electrical equipment, such as transformers and circuit breakers, under standardized conditions, expressed in amperes, kilovoltamperes, kilowatts, volts, or other appropriate units. Usually indicated on a nameplate attached to the individual machine or device.
Federal health-based standards on allowable ambient air concentrations for a set of known pollutants.
Written standards, providing basic requirements for the design, construction, maintenance, and operation of electric supply and communication lines, equipment, and supply stations in order to safeguard persons from hazards associated with those activities.
A 1969 Federal law that requires evaluation of the environmental impact of Federally funded projects and programs. Generally requires an environmental assessment and/or an environmental impact statement be submitted to the Federal government before a project can begin.
An agency of the U.S. Department of Commerce that oversees ocean and river fish harvest limits and determines which stocks are to be listed as endangered or threatened under the Endangered Species Act.
A provision of the Clean Water Act that prohibits discharge of pollutants into waters of the U.S. unless a special permit is issued by the Environmental Protection Agency, a State, or (where delegated) a tribal government on an Indian reservation.
The Environmental Protection Agency’s annually updated list of the most serious uncontrolled or abandoned hazardous waste sites in the U.S. identified for possible long-term cleanup under the Superfund. The list is based primarily on the score a site receives from the Hazard Ranking System.
National Response Center
The Federal operations center, operated by the U.S. Coast Guard, that receives notice of all releases of oil and hazardous substances into the environment, and evaluates and notifies the appropriate agency.
Heat transferred through a fluid medium, such as air or water, by currents that result from the rising of less dense, warm fluid and the sinking of heavier, cooler fluid.
Traditionally, waters sufficiently deep and wide for navigation by all, or specified sizes of vessels. Such waters in the United States come under Federal jurisdiction and are included in certain provisions of the Clean Water Act.
See National Environmental Policy Act.
See National Electric Safety Code.
Washington Public Power Supply System Nuclear Projects 1, 2, and 3 and the Trojan Nuclear Plant.
1) In general, offsetting payments due to one party against payments due the other party. 2) A method used by BPA to acquire its preference customers’ entitlement to shares of project capability for (power output from) Trojan and the Washington Public Power Supply System Projects 1, 2, and 3. Accomplished by crediting the preference customers’ costs in those projects against power sales revenues due BPA.
The amount of energy available to the ultimate user compared to all the energy inputs involved in producing that energy. The net energy of a coal-fired electrical system would be the ratio of the energy of the produced electricity to the sum of the energy inputs required, including energy for mining, transporting and processing the coal, energy for operating a power plant, and energy losses in the plant and transmission and distribution systems.
See present value.
On BPA’s year-end financial statement. The amount by which total revenues exceeded total operating expenses, or vice versa. The bottom line.
1) A system of interconnected circuit components. 2) A system of transmission (or distribution) lines interconnected and operated so that any principal point has multiple sources of power supply.
A transmission circuit connected at each end to other lines within the network or system. Also see radial line.
Any load associated with a new facility, an existing facility, or an expansion of an existing facility that is not contracted for, or committed to, (as determined by the BPA administrator, by a public body, cooperative, investor-owned utility, or Federal agency customer prior to September 1, 1979), and that will result in an increase in power requirements of the customer by 10 average megawatts or more in any consecutive 12-month period. The costs of serving such loads are excluded from a utility’s average system cost under the residential exchange. Determined by section 3 (13) of the Pacific Northwest Electric Power Planning and Conservation Act.
See rates.
Environmental Protection Agency emission standards for air and water that limit the amount of specified pollutants allowed from new or modified sources.
Nonfirm energy rate. See rates.
A negative term used for problems arising when siting garbage dumps, radioactive dumps, or electric facilities.
A gas formed in great part from atmospheric nitrogen and oxygen when combustion takes place under high temperature and high pressure. Not in itself a pollutant, in the ambient air NO converts to nitrogen dioxide, a major contributor to photochemical smog. Also see photochemical smog.
A reddish-brown gas that forms during high temperatures of combustion. Is toxic at high concentrations and reacts with moisture in the air to form nitric acid, which is highly corrosive to metals. Is a key ingredient in the formation of photochemical smog and acid rain. Also see photochemical smog.
Compounds produced by combustion, particularly when there is an excess of air or when combustion temperatures are very high. NOx are primary air pollutants.
A condition of water in which the concentration of dissolved nitrogen exceeds the saturation level of water. Excessive nitrogen can harm the circulatory systems of fish. Nitrogen supersaturation can be caused by turbulence as water is spilled over a dam.
See new large single load.
See National Marine Fisheries Service.
See notice of insufficiency.
See discount rate.
Dollars spent that include inflation. Also known as current dollars. See real dollars.
See levelized costs.
The voltage by which the system is designated and to which certain operating characteristics are related, and near the voltage level at which the system operates (generally is about 5 to 10 percent below the maximum system voltage for which system components are designed).
Those public utility customers of BPA who own or control little or no generation capability and who purchase all or almost all of the power required to serve their loads from BPA. Also referred to as full-requirement or metered-requirement customers.
A geographic area that does not meet one or more national air quality standards.
See insulator.
See demand.
Resources brought into service after June 1980 by BPA customers who choose not to use them to serve their own firm loads.
See costs.
Access to an intertie for energy sales on a nonfirm basis.
A method used by BPA to allocate use of intertie transmission lines on an hourly basis for sales other than long-term firm power sales.
See energy.
See rates.
Sales of electricity that are not guaranteed, but are interruptible under specified conditions.
See power types.
See sales.
A utility that does not own or contract for generation to serve its loads but buys power from suppliers.
source of pollutants, generally carried off the land by storms and runoff, that is spread out and has no single point of origin. Common categories include agriculture, forestry, urban areas, mining, construction, dams, and channels.
Natural resources, such as oil or minerals, that are present in finite supply and are not renewed by a natural system as quickly as they are used.
See conductor.
See reserve.
Refers to active water storage space in the Canadian portion of the Columbia River Basin that is in excess of storage specifically operated according to the Columbia River Treaty.
A 1983 agreement between B.C. Hydro and BPA, and between BPA and non-Federal utilities, to cooperatively use active storage space in B.C. Hydro’s Columbia mainstem projects that is in excess of that outlined in the Columbia River Treaty. A new agreement was signed in 1990.
An entity that is not a utility that develops and operates a generating plant.
A council consisting of nine Regional Reliability Councils, encompassing virtually all of the power systems in the U.S. and Canada. Formed by the electric utility industry in 1968 and incorporated in 1975 to promote reliable and adequate supplies of bulk electric power.
Those BPA facilities associated with interconnection with Canadian utilities. Specifically, two 500-kV lines from BPA’s Custer Substation to B.C. Hydro’s Ingledow Substation, and 230-kV ties at Boundary Substation to B.C. Hydro and West Kootenay Power and Light.
See Pacific Northwest Conservation and Electric Power Plan.
An eight-member council, established by the Pacific Northwest Electric Power Planning and Conservation Act. Comprised of two voting members from the four Northwestern states—Washington, Oregon, Idaho, and Montana. Helps guide BPA and the region with planning for conservation and generation resources and for protection, mitigation, and enhancement of fish and wildlife in the Columbia River Basin.
A regional cooperative power operating and planning group, formed in 1941 with representatives from the U.S. Army Corps of Engineers, Bureau of Reclamation, BPA, and the region’s public and private utilities with generating resources; coordinates river flows and operations to supply power in the most economical manner for combined load requirements.
A 1976 BPA letter notifying its customers of inadequate resources to meet in full its future estimated loads. Requirement of the current BPA power sales contracts.
A public notice that an environmental impact statement will be prepared and considered in the decision making for a proposed action.
See National Pollutant Discharge Elimination System.
See National Priorities List.
Net present value. See present value.
See Nuclear Regulatory Commission.
New resource firm power rate. See rates.
See non- and small-generating public utilities.
See new source performance standards.
See Non-Treaty Storage Agreement.
See fuel.
An electric power plant that converts nuclear energy into electrical energy. Heat produced by a reactor is used to make steam to drive a turbine that in turn drives an electric generator.
A device in which a nuclear fission chain reaction can be initiated, maintained, and controlled.
A nuclear reactor in which water is boiled in the core and the resulting steam drives a turbine to generate electricity.
A nuclear reactor that produces fissionable material faster than it consumes it. The new fissionable material is created by neutron capture in fertile material by a process known as breeding.
A nuclear reactor in which helium gas is the coolant with graphite fuel elements containing coated particles of highly enriched uranium plus thorium. Offers greater thermal efficiency than light water reactors.
A nuclear reactor that uses ordinary water as moderator in contrast to heavy water.
A nuclear reactor in which closed primary and secondary loops are used, with the water coolant in the primary system pumped through the reactor vessel, transporting the heat to a steam generator, and the separate secondary water system producing steam in the steam generator for the turbine generator.
The Federal agency that regulates, inspects, and oversees all activities involved with nuclear power plant generation to assure the safety of U.S. nuclear power plants.
See non-utility generator.
See Northwest Power Pool.



1) A legal term expressing legal, moral, and governmental commitments to specific courses of action, such as BPA’s obligation to provide firm power to small- and non-generating public utility customers. 2) Capacity and energy BPA provides under contract to public agencies and private utilities.
Actual measurements of end-use consumption of electricity by metering.
In risk management, an accident, including continuous or repeated exposure to conditions, that results in bodily injury or property damage neither expected nor intended from the standpoint of the damaged party.
A document published by a bond issuer which generally discloses material information on a new issue of municipal securities including the purposes of the issue, how the securities will be repaid, and the financial, economic, and social characteristics of the issuer. Investors may use this information to evaluate the credit of the securities.
Refers to a period of relatively low demand on an electric system. Typical offpeak hours are in the middle of the night.
See energy.
A hazardous waste treatment, storage, or disposal area that is located at a place away from the originating site.
The unit of resistance and impedance. One ohm is the resistance of a conductor such that a constant current of one ampere produces a voltage of one volt between the ends of the conductor.
The relationship in a circuit between voltage, current, and resistance or impedance. The law states that the current in an electric circuit is inversely proportional to the resistance or impedance, and is directly proportional to the voltage.
Refers to a period of relatively high demand on an electric system.
See energy.
A hazardous waste treatment, storage, or disposal area that is located on the originating site.
In a circuit breaker or other switching device, the state when the switch contacts are apart, the switch is “off,” and current cannot flow. The opposite of closed.
See system operating constraints.
The level (one of the four possible quartiles) in the direct-service industries power sales contracts that defines BPA restriction rights and the DSIs’ curtailment rights.
See expenses.
1) A plan prepared each year, encompassing the August 1 through July 31 operating year, to determine how much load can be served with existing resources. 2) In the direct-service industries power sales contract, refers to BPA’s annual plans to serve DSI load.
The guidelines and limits within which a reservoir or generating project must be operated, originating in authorizing legislation, physical plant limitations, or operating experience.
All the revenues resulting from the ongoing operations of BPA. Net interest income is excluded, as it is netted with interest expense.
A composite curve, derived from a family of curves, indicating how a reservoir is to be operated under specific conditions. Accounts for multiple operating objectives, including flood control, hydropower generating, releases for fish migration, and refilling reservoirs.
The 12-month period from August 1 through July 31 (OY 1994 is August 1, 1994 through July 31, 1995). Also see calendar year, fiscal year.
The adjustment allowed to the monthly Firm Energy Load Carrying Capability during the operating year. Generically, the "slack" in a system that permits running the system at slightly higher or lower rates to achieve immediate or short-term goals.
See synchronized operation.
See cost.
See sales.
1) In resource planning, the purchase of a right to acquire a resource within a particular time on specified terms. 2) In land acquisition, a written commitment for a specified time and specific conditions to sell property or a property right.
An instrument used to produce a record of the instantaneous values of one or more rapidly varying electrical quantities as a function of time. To analyze system troubles, automatic oscillographs at BPA substations provide a record of voltage and current variations on the transmission lines. Also see digital fault recorder.
In a power system, a period, scheduled or unexpected, during which the transmission of power stops or a particular power-producing facility ceases to provide generation.
Results when a component unexpectedly fails to perform its function or is shut down for emergency reasons.
Results when a component is deliberately taken out of service at a selected time, usually for purposes of construction, maintenance, or testing.
The place where wastewater, treated or untreated, is discharged into receiving waters.
Payment on obligations. For a budget, this also includes non-cash transactions such as net-billing.
1) An abnormal condition resulting when parts of a system (electrical or otherwise) do not operate together. 2) In an electrical system, an abnormal condition resulting from loss or lack of synchronism between parts. For example, when the phase angle representing voltages on two parts of a system exceeds the normal value.
Fish hatched and initially reared in a hatchery, which are then transplanted to natural habitats to continue juvenile rearing.
The current, voltage, power, or driving force delivered by a circuit or device.
See relay.
See spill, inadvertant.
See ground wire.
Operation of equipment in excess of its normal, full load rating or operation of a conductor in excess of ampacity, and if continued for a sufficient length of time, would cause damage or overheating.
The maximum load that a machine, apparatus, or device can carry when operating beyond its normal rating, within the limits of considered capability as determined by the manufacturer or user.
Any chemical that increases the oxygen content of another compound or causes a compound to lose electrons. A compound that readily gives up its oxygen or removes hydrogen from another compound.
See nitrogen oxide.
See operating year.
1) A highly reactive form of oxygen naturally occurring in the stratosphere (atmospheric layer beginning 11 to 16 kilometers (7 to 10 miles) above the earth’s surface). Provides a protective layer shielding the earth from ultraviolet radiation’s harmful health effects on humans and the environment. 2) Associated with the corona discharge of high-voltage transmission lines. Rapidly recombines back to O2.
Destruction of the naturally occurring layer of ozone by the breakdown of certain chlorine- and/or bromine-containing compounds, such as chlorofluorocarbons.