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The amount of electricity sold to a retail utility or direct-service customers.
Sales of power on a guaranteed basis for a specified length of time, pursuant to a contract.
Sales of power in varying amounts depending on season and weather conditions; continuous availability is not guaranteed.
Energy sales dependent on non-Treaty storage and the Non-Treaty Storage Agreement, and not governed by the constraints in the Pacific Northwest Coordination Agreement.
Sales of surplus power, both firm and nonfirm, in the Pacific Northwest.
Sales of power of duration less than four years within the critical planning period or of duration less than one year within the operating year.
See forecast.
Fish that spends its one- to three-year adulthood in salt water and returns to fresh water streams to spawn. Pacific Northwest salmon include chinook, sockeye, and coho.
Fish belonging to the family of salmonidae, including salmon, trout char, whitefish, and allied freshwater and anadromous fish.
See system analysis model.
Superfund Amendments and Reauthorization Act. See Superfund.
See supervisory control and data acquisition.
See station control error.
People working at a control center, who, working with dispatchers, direct the amount of power flowing over a power grid, fulfilling a variety of contracts and obligations.
See outage.
1) A generating utility that operates a generation control area. See generation control area. 2) BPA computed requirements customers.
See generating public utilities or investor-owned utilities.
1) A generating utility that operates a generation control area. 2) BPA computed requirements customer of BPA. Not all have generation control areas. See generation control area.
A diagram of electric circuits, with graphical symbols representing components.
For an environmental impact statement, the process of defining the range of issues requiring examination in studying the environmental effects of a proposed action, generally including public consultation with interested individuals and groups, as well as with agencies with jurisdictions over parts of the project area or resources in that area.
A device that conducts the water from the penstock around the turbine runner in a hydropower system.
A type of air pollution control device.
Collects airborne particulates by direct contact with a liquid, usually water.
Differences between two or more power systems. For example, in the Pacific Northwest and Pacific Southwest, their annual peak loads are in different seasons of the year.
A rating used to compare one cooling system to another using average efficiency over time and a range of temperature under which a unit operates. Specifically the total cooling Btu of a central air conditioner (heat pump) during its normal usage period for cooling (not to exceed 12 months), divided by the total electric energy input in watt-hours during the same period.
See exchange agreement.
See load shaping.
See storage.
See energy.
Loads that can be served with nonfirm energy whenever it becomes available.
Revenues received from sales of secondary energy.
secondary sales
See sales.
The opening or disconnecting of a transmission line or substation bus to permit isolation of equipment or line sections to do work or locate trouble.
1) A large group of consumers with similar uses for electricity and similar conservation or generation opportunities; also called consumer group. 2) In demand side management, often called an end-use sector.
The group of consumers who use electricity in trade and service buildings, such as offices, schools, retail stores, warehouses, hotels, and hospitals, and are not involved in manufacturing or extraction. Street lighting accounts are classified as commercial; multifamily dwellings four levels or more above grade and common use spaces of all multifamily dwellings are classified as commercial. In multifamily structures less than four levels above grade and used exclusively for residences, only the common use spaces are considered commercial. Housing projects normally consist mainly of residential accounts with some small commercial support services, although a utility might sell power on a single meter to the entire project at a commercial rate.
The group of consumers who use electricity in manufacturing (such as lumber, pulp and paper, food, electronics, chemicals, and transportation equipment) or mining. This sector is often split into direct-service industrial and non-DSI load for analyses and programs, due to the unique characteristics and high consumption levels of the DSI aluminum smelters. BPA’s utility customers often identify large commercial accounts, such as single-metered shopping centers, as industrial load due to the practice of classifying sectors based on load size.
The group of consumers who use electricity for such purposes as pumping, spraying crops, and stock pumps used for pasturage. Domestic water pumping is often included as irrigation if no distinction is made on utility rate schedules between residential and irrigation pumping or if the reported data are mixed.
The group of consumers who use electricity in residential, farm, apartment, and seasonal dwellings for such purposes as space and water heating, cooking, and lighting; overlaps the commercial sector when businesses operate in homes.
See seasonal energy efficiency rating.
A process used for rate setting in which BPA allocates rate period transmission revenue requirements to customer classes according to their projected use of the transmission system. To ensure that allocated costs correspond to services provided, the facilities of the transmission system (and their associated costs) are divided among nine categories of service, or segments.
1) In communications, the degree to which a device can accept signals of one frequency or band of frequencies while rejecting all other frequencies. 2) In power system control, the degree to which the interrelated performance of relays and circuit breakers and other protective devices keep to a minimum the amount of equipment taken out of service for isolation of a fault.
A computer-based system at the Dittmer Control Center that continuously gathers and saves data from a number of sequential events recorders; data from many of the recorders can be displayed in chronological order to determine if the substation equipment operated correctly.
A computer-based system at a substation that gathers critical data about the substation’s operation; the data is stored in the recorder in the order it occurred.
See capacitor bank.
See resonance.
Direct-service industrial rates. See rates.
See sulfur hexafluoride gas.
See load shaping.
See ground wire.
A conductor or conductors strung as a temporary substitute for a more permanent installation; can be in a substation as a substitute for a section of bus or a short section of transmission line.
An abnormal connection between two or more points in a circuit. May be either deliberate (as in a protective grounding) or accidental (as in a system fault).
BPA purchases of power normally for less than a year but can be up to five years.
short-term sales
See sales.
A device having resistance or impedance connected in parallel across other devices or apparatus, and diverting some of the current from it.
See capacitor bank.
International System of Units. The modern metric system of measurement.
The ratio, at any point on a circuit, of signal power to total-circuit noise power, usually expressed in decibels (db).
The eventual depositing of finely divided particles of soil and rock suspended in moving water upon the gravel of stream and riverbeds. Siltation has a very harmful effect upon the ability of fish to spawn successfully.
The representation of an actual system by means of a mathematical model (for example, a power flow is a simulation of an actual power system and provides data on how the system will perform under conditions studied).
See circuit.
See conductor configurations.
The tripping and reclosing of one pole of a multipole circuit breaker without opening the other two phases. Applied at 500 kV where the three poles (phases) of a 500-kV circuit breaker can be independently operated. Requires protective relays that respond selectively to the faulted phase.
See circuit recloser.
The shape of a wave form such as an alternating current or voltage that has alternating positive and negative cycles (sine wave).
See State implementation plan.
The return to original or natural or enhanced natural condition of a locale that has been used or proposed to be used for some human enterprise.
The process of locating a site for a facility, such as a power plant or transmission line, including meeting any applicable regulations and obtaining the necessary licenses and permits.
A semi-solid material left from any of a number of air or water treatment processes or industrial processes. Can be a hazard to human health or the environment.
The downslope movement of a mass of rock or soil.
As used by BPA, hydroelectric projects capable of producing 25 average megawatts or less.
A freshwater fish that is a natural predator of salmon.
A facility that melts or fuses ore, often with an accompanying chemical change, to separate the metal. Smelting is the process involved.
A young salmon or steelhead migrating to the ocean and undergoing physiological changes to adapt its body from a freshwater to a saltwater environment.
Water from melting snow.
In forecasting, a measure of the amount of water expected from the spring melting of snowpacks.
A small Pacific salmon that migrates through the Columbia-Snake River system and spawns at high elevation and great distance from the ocean.
A semiconductor device that converts light into electrical energy. Also see photovoltaic generation.
The heat or electricity produced from sunlight. Also see active solar system, passive solar.
An optical device with large mirrors that focuses the rays from the sun upon a small focal point to produce very high temperatures.
The process by which BPA asks for bids on products, materials, services, or resources to be acquired.
A liquid capable of dissolving or dispersing one or more substances.
See system operation review.
See sum of utility forecast.
The origin of funds to be used for Federal Columbia River Power System capital investments, such as generation, conservation, transmission, and fish and wildlife projects. Potential sources include bonds issued to the U.S. Treasury, congressional appropriations, third-party sources, and current revenues.
Controlling the conditions inside a building in order to maintain human comfort and other desired environmental conditions through heating, cooling, humidification, dehumidification, and/or air quality modifications.
A mechanical device attached to each subconductor of a conductor bundle to prevent physical contact of subconductors. Also see interphase spacer.
A mechanical device attached to each subconductor of a conductor bundle both to damp vibrations and to prevent physical contact of subconductors.
The horizontal distance between two adjacent supporting points of a conductor.
The act of fish laying and fertilizing eggs.
See remedial action scheme.
See remedial action scheme.
1) The amount of heat (usually measured in joules, or Btu) required to raise the temperature (usually in Fahrenheit) of a given mass of a substance one degree or the amount of heat given up when it is cooled one degree. 2) The amount of heat, measured in joules, or Btu, for a given mass, that a material can hold when its temperature is raised one degree F.
Water that goes over the spillway of a dam rather than through turbines.
Water for which there is no storage capability in the system reservoirs and flows exceed turbine capacity.
Overgeneration spill; water which could have been used to generate electricity but was not because of lack of available market, and inability to store for later use.
planned spill; water intentionally passed through a dam without producing electricity, usually for the benefit of fish; not the same as water budget.
The channel or passageway around or over a dam through which water flows, or is “spilled,” past the dam without passing through the turbines.
See reserves.
Fish sought by recreational anglers. Also called game fish.
A temporary market for electricity based on short-term supply and demand.
The market price for a sale of surplus power for which the buyer and seller have no long-term obligations; often made on an hourly or weekly basis.
Surplus power rate. See rates.
A freshwater fish that preys on salmon.
The attribute that enables a dynamic system to develop restoring forces equal to or greater than disturbing forces so as to maintain a state of equilibrium. The antithesis of cascading. Power station stability requires maintaining synchronism of generators and maintaining voltage at loads.
See remedial action scheme.
Gases such as carbon dioxide, water vapor, and nitrogen and accompanying particulates that result from combustion or industrial processes and which are discharged through a chimney or similar structure.
See reservation fee.
State plans approved by the Environmental Protection Agency for establishing, regulating, and enforcing air pollution standards.
A controllable var supply, consisting of a complete system of static components (capacitors, reactors and solid-state switches) combined in one device, to provide rapid and continuously controllable reactive compensation for sudden surges in voltage.
A signal transmitted automatically and continually to a power plant to adjust generation which, along with adjustments at other power plants, will make generation match requirements in the overall power system. Also see area control error, automatic generation control.
1) Facilities that provide energy for local use at a generating plant or substation (for lighting, heat, and the operation of auxiliary equipment). 2) The power that serves those loads.
An electronic device used to simultaneously transmit and receive several digital messages over a common communication path. Messages are transmitted and received in a statistically random fashion.
The stationary electromagnetic portion of an electric motor or generator.
See turbine.
A rainbow trout or steelhead trout that spends its adulthood in saltwater and returns to freshwater streams to spawn.
Tapered steel tubes in the shape of a pole. Used primarily for aesthetic reasons as supports for transmission lines.
See transformer.
See transformer.
A regulating transformer in which the voltage of the regulated circuit (load circuit) is controlled by steps by means of taps and without interrupting load. Voltage regulators are used primarily at distribution voltages on long or heavily loaded circuits to help maintain voltage levels.
A discrete or specific subset of a fish species, with isolation in space and/or time from other subsets of the same species.
1) The volume of water in a reservoir at a given time. Gross storage is the total volume of water in a reservoir at normal full pool. Also see reservoir. 2) The exchange of energy generated at one time for energy used at another time.
The volume of storage that can be withdrawn, as needed, for multiple uses downstream. Also called live storage.
The space that is filled when a reservoir initially fills and is unavailable thereafter due to physical or operating constraints or because it lies lower than the penstock openings on the dam. Also called dead storage.
A reservoir filled with water by pumping during offpeak demand periods. The stored water can be used to meet peak loads.
seasonal storage
1) Water held over from the annual high-water season to the following low-water season. 2) In power sales contracts, the ability to store water in reservoirs and thereby change the energy generation at hydroelectric facilities in one month and compensate for such change in another month.
Water occupying active storage capacity of a reservoir.
See conductor.
The rate at which water passes a given point in a stream or river, usually expressed in cubic meters, or cubic feet, per second.
See forecast.
See insulator.
A device that records on a chart one or more varying quantities simultaneously as a function of time (for example, voltage, frequency, megawatts, megavars).
To mine coal by removing covering material and stripping away the entire underlying coal seam.
See insulator.
See mechanical loads.
See submersible traveling screen.
The reinforcement of a wood pole by installing a short stub pole adjacent to the wood pole and securing the two together. Avoids replacement of entire pole.
One of the individual conductors that make up a conductor bundle.
A mechanical device for diverting fish out of powerhouse turbine intakes and into holding facilities where the fish are collected, tagged, and trucked or barged downriver. Also see fish screen.
An insurer’s right to recoup payment on an insured’s claim from a wrongdoer who is not the policyholder.
A non-generating electrical power station that serves to transform voltages to higher or lower levels, and serves as a delivery point to individual customers such as utilities or large industries. BPA grid has more than 400 substations. Also see switching station.
A juvenile salmonid, normally a fall or summer chinook salmon, that hatches and migrates to the ocean in the same year.
One of the gases composed of sulfur and oxygen produced by the combustion of fuels containing sulfur and a key ingredient in the formation of smog and acid rain.
A gas widely used in high-voltage circuit breakers and gas-insulated substations; has a high thermal conductivity and a high dielectric strength (twice that of air under comparable conditions) that facilitates arc quenching in a circuit breaker and provides insulation in a gas-insulated substation.
See forecast.
A property of a material characterized by zero electric resistivity and, ideally, zero permeability. Exhibited by certain materials at extremely low temperatures.
The Federal cleanup program under the 1980 Comprehensive Environmental Response, Compensation, and Liability Act and 1986 Superfund Amendments and Reauthorization Act.
The centralized computer system that includes transmission of numerical quantities and alarms from substations to a control center.
A traditional economic tool used to depict the amount of a product available across a range of prices.
See forecast.
A computer model used by BPA to forecast electricity prices.
A power-generating resource. In contrast to a power-saving resource such as conservation (demand-side).
See Washington Public Power Supply System.
Under the Pacific Northwest Electric Power Planning and Conservation Act, an additional sum added to the usual wholesale power rate charged to a utility customer of BPA to recover costs incurred by BPA due to the failure of that customer (or of a State or local government served by that customer) to achieve conservation savings comparable to those achievable under the Northwest Power Planning Council’s Model Conservation Standards.
1) All water naturally open to the atmosphere, such as rivers, lakes, reservoirs, streams, impoundments, seas, and estuaries. 2) Refers to all springs, wells or other collectors that are directly influenced by surface water.
A device designed to protect electric equipment from high-transient voltage by diverting a momentary overvoltage (lightning or switching) to the ground. Usually connected between phase conductors and the ground, and located close to a transformer or reactor, a surge arrester allows the overvoltage to dissipate, and then to restore itself to its initial non-conducting state.
A surge arrester that uses metal oxide instead of previously used silicon carbide for the non-linear valve elements. The metal oxide valve elements require no series gaps (used in older silicon carbide arresters). Sometimes referred to as a metal oxide varistor.
See capacity.
See energy.
See capacity.
See energy.
See power type.
See rates.
See energy.
See capacity.
See power types.
The conductor support on transmission-line suspension structures. Attaches to an insulator string to hold the conductor.
See insulator.
A string of insulators suspended from a power structure crossarm to support the conductor. May be single or double strings depending on tower design.
See tower.
The peaking capacity necessary to carry a load for a given period of time.
Using a renewable resource at a rate that permits the resource to regenerate itself for continuing use undiminished into the future.
See anchor.
The tendency of some part of a power system to move toward being out of step with another part of the system, usually as a result of a disturbance. See stability.
A general term covering various switching and interrupting devices used in a power sys-tem; including disconnecting switches (isolating devices), circuit breakers, circuit switchers, and automatic circuit reclosers (interrupting devices).
An installation of equipment where several transmission lines are interconnected. Does not include equipment for transforming voltage levels. Also see substation.
See fuse pole.
The outdoor portion of a substation.
The state when connected alternating-current systems, machines, or a combination operate at the same frequency, and the phase-angle displacements between voltages are relatively constant. Same as operation in parallel.
A computer model that simulates, monthly for 20 years, the operation of the Pacific Northwest hydro/thermal power system, taking into account the uncertainty associated with hydropower, thermal availability, new resources, and load fluctuation due to economic cycles. Provides information regarding the expec-ted operation of the hydroelectric system and individual thermal resources, the reliability of the system, production costs, and sales and revenues.
See capacity.
The status of all components within a single system. For BPA, that includes water runoff, generators, nonpower constraints, transmission lines and equipment, interties, loads and active contractual agreements for buying, storing, selling, transmitting, and exchanging power.
See control center.
According to the Pacific Northwest Electric Power Planning and Conservation Act, all direct costs of a measure or resource over its effective life, including, if applicable, distribution and transmission, waste disposal, end-of-cycle, and fuel costs and quantifiable environmental measures.
The repetition rate in hertz (cycles per second) of a power system's alternating voltage; nominal system frequency is 60 hertz.
See losses.
Limits on the amount of power the Federal hydro system can produce, due to other uses of the dams and reservoirs such as to provide flood control, irrigation, river transportation, and fish passage.
A public involvement process conducted by BPA, the Bureau of Reclamation, and the U.S. Army Corps of Engineers on the operation and use of the Federal Columbia River Power System leading up to two key events—the pending expiration in 2003 of the Pacific Northwest Coordination Agreement among U.S. parties who operate the U.S. dams in the FCRPS and the end of the sale period of the Canadian Entitlement. The agencies review multiple, and often conflicting, uses of Columbia River water for fish, power, irrigation, transportation, recreation, and flood control.
The annual refilling of reservoirs, Federal and non-Federal, and considered as a whole, that influence the operation of the Federal hydro system.
The survival of migrating juvenile salmon or steelhead of a particular stock from its point of entry into the hydroelectric system to a point below Bonneville Dam.