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See Celsius.
See Clean Air Act.
A conductor with insulation (single conductor cable) or a combination of conductors insulated from one another (multi-conductor cable). Cables up to 115 kV usually have solid type insulation; cables rated 230 kV and above are oil-filled.
control and instrument cable
Two-conductor up to 12-conductor with 600/1,000 volt insulation.
Optical fibers incorporated into an assembly of materials that provide tensile strength and external protection, and have handling properties comparable to metallic cables.
Available from 2.4 kV up to 800 kV with current ratings up to 1,200 amperes. At lower voltage either single-phase or three-phase, while at higher voltage single-phase only.
See computer-aided design.
The 12-month period from January 1 through December 31. See fiscal year, operating year.
A 500-kilometer (300-mile) transmission line between southern Oregon and the San Francisco Bay Area, managed by the Transmission Agency of Northern California, to increase Pacific Northwest-Pacific Southwest intertie capacity. Also see Third AC.
A power sale contract provision that gives the seller the right to stop delivery of power to the buyer when it is needed to meet other specified obligations of the seller.
Originally, the amount of heat energy required to raise the temperature of one gram of water one degree C, but because this quantity varies with the temperature of the water, the calorie has been redefined in terms of other energy units. One calorie is equal to 4.2 joules.
Short for Canadian Entitlement Exchange Agreement. Under the Columbia River Treaty, Canada’s 50-percent share of the increase in usable energy and capacity downstream from, and based on the filling of three reservoirs at Duncan, Keenleyside, and Mica storage dams in Canada and the reservoir behind Libby Dam in Montana.
A non-profit entity composed of Northwest public and private utilities that bought Canadian Entitlement rights for 30 years from the filling of each of the Columbia River Treaty reservoirs.
The maximum load a generator, piece of equipment, substation, or system can carry under specified (standardized) conditions for a given time interval without exceeding approved limits. Sometimes used interchangeably with capacity, although not a synonym. Also see rating.
In BPA power sales contracts, the firm peak and firm energy capabilities for each of the purchaser’s firm resources that the purchaser dedicates to serving their firm loads.
The maximum output of a generating plant or plants during a specified peak-load period.
Creating the knowledge, tools, work force, and processes necessary for BPA to acquire conservation on a large scale within a sector of the economy when savings are needed, including pilot programs, demonstration pro- jects, and research and development projects from which programs may result, such as weatherization.
A curve developed for gener- ators showing the limits of reactive and active power that a generator can produce without overheating or becoming unstable.
That property of an arrangement of conductors and dielectrics that stores energy in the form of an electrical charge when potential differences exist between the conductors. See inductance.
1) In a power system, installed to supply reactive power. See reactive power. 2) A device to store an electrical charge (usually made of two or more conductors separated by a non-conductor such as glass, paper, air, oil, or mica) that will not pass direct current and whose impedance for alternating current frequencies is inversely proportional to frequency. 3) In a power system, capacitors consist of metal-foil plates separated by paper or plastic insulation in oil or other suitable insulating fluid and sealed in metal tanks.
A grouping of capacitors used to maintain or increase voltages in power lines and to improve system efficiency by reducing inductive losses.
An installation of capacitors with fuses and associated equipment in series with a line. Generally located near the center of a line (but can be located at any point). Used to increase the capability of interconnections and in some cases to achieve the most advantageous and economical division of loading between lines operating in parallel.
An installation of capacitors with fuses and associated equipment; generally located in substations, and used to increase system voltage and to improve the power factor at the point of delivery.
See transformer.
The maximum load that a generator, piece of equipment, substation, transmission line, or system can carry under existing service conditions. Sometimes used interchangeably with capability, although not a synonym.
The dependable capacity of system facilities available for serving system load after allowance for required reserve capacity, including the effect of emergency interchange agreements and firm power agreements with other power systems.
In electricity production, the power output that can be continuously produced, usually computed by considering equipment that the operator/utility intends to run at least 70 percent of the time.
The amount of capacity that can be sustained for 10 hours a day, five days a week, during peak-load hours.
Capacity whose availability is assured to the purchaser. The purchaser is usually required, under contract provisions, to replace the energy associated with the delivery of firm capacity.
The total of the capacities shown by the nameplate ratings of similar kinds of apparatus, such as generators, transformers, or other equipment in a station or system.
The maximum capacity of a sys-tem to meet loads. Also called peak-load capacity.
1) The generating capacity available to assist in meeting that portion of the load that is above baseload. 2) The maximum output of a generating plant or plants during a specified peak-load period.
Extra generating capacity available either to meet unanticipated demands for power or to generate power in the event of loss of generation resulting from scheduled or unscheduled outages of regularly used generating capacity. Reserve capacity to meet the latter situation also known as forced outage reserve.
1) The amount of electrical capacity above the amount needed to meet the current load requirements of BPA customers. 2) The amount of excess intertie capacity available after reserving sufficient capacity for sale of BPA surplus firm and nonfirm energy.
Capacity for which there is no regional market at the established price.
Electric peaking capacity for which there is no demand in the Pacific Northwest at the rate established for the disposition of such capacity.
The difference between dependable capacity of an electrical system (including purchases, options, exchanges, and so on) and the actual or anticipated peak load for a specified period of time.
New equipment added to increase the amount of power that existing transmission facilities can carry.
A transaction in which one utility provides a second utility with capacity service during the second utility’s peak season and in return receives energy during its peak season; this type of exchange benefits utilities that do not peak at the same time.
The ratio of the average load on a generating resource to its capacity rating during a specified period of time, expressed in percent.
A system of pricing that includes only a single annual or monthly demand charge with no separate charge for the amount of energy used by the purchase.
See nameplate rating.
The service whereby one utility delivers firm energy during a second utility’s period of peak usage with return made during the second utility’s offpeak periods; compensation for this service may be return energy or money.
See value.
A budget item that refers to a facility or system addition that has multi-year benefits, usually funded through borrowing and repaid over the useful life of the project.
capital costs
See costs.
For BPA, an outlay of money for such purposes as construction of transmission system facilities and fish hatcheries, and for the acquisition of conservation resources. Typically funded through borrowing from the U.S. Treasury; annual interest and depreciation are funded by BPA revenues, and therefore are included in BPA’s revenue requirements.
For BPA, U.S. Treasury borrowing, customer third-party financing, and the use of cash reserves to finance capital projects.
The budget programs that fund the development of assets and normally call for investment in depreciable or amortizable assets, which includes transmission and general plant physical assets which are tangible capital assets. Intangible assets of conservation and renewable resource acquisition investments may also be included. Funded by borrowings from the U.S. Treasury or by revenues from sales.
1) A gas found in nature in the free state and also produced by burning fossil fuels such as coal, oil, and natural gas. 2) One of a group of gases, called greenhouse gases, that trap heat in the earth’s atmosphere.
A colorless, odorless gas which is the product of incomplete combustion when natural gas, oil, wood, coal, or other materials rich in carbon are burned. Carbon monoxide interferes with the delivery of oxygen throughout the body.
1) In electrical terms, the same as capacity. 2) In wildlife management, the maximum number of animals an area can support during a given period of the year. 3) In recreation management, the amount of use a recreation area can sustain without deterioration of its quality.
1) In a power system, the tendency of a local line fault to trigger problems elsewhere on the system and lead to a widespread power outage. 2) In a transmission line, a succession of mechanical failures along the line caused by one event such as a broken insulator.
The residual after adjusting net reve-nues for expenses not requiring cash, changes in accrued revenues and expenses, cash used for investments, and cash from borrowing and appropriations.
A class of actions, defined by Department of Energy rules, that either individually or cumulatively would not have a significant effect on the human environment and therefore would not require preparation of an environmental assessment or environmental impact statement under the National Environmental Policy Act.
The curve formed by a conductor between points of suspension at adjacent towers.
The electrode from which current flows to an external circuit.
A tube, as in a TV set or computer monitor, in which a beam of electrons can be focused on luminescent particles on a screen and varied in position and intensity to produce a visible pattern.
The reduction or prevention of corrosion by making a metal the cathode in a conducting medium by means of a direct current; corrosive metal loss occurs at anodes only.
The pitting corrosion (erosion) on the turbine blades and the runner of hydrogenerators caused by low water pressures.
See Columbia Basin Fish and Wildlife Authority.
Cooling degree day. See degree day.
A scale for measuring temperature where water freezes at 0 degrees Celsius and water boils at 100 degrees Celsius. Degrees Celsius and degrees Centigrade are the same.
Same as degrees Celsius. Celsius is the preferred form. See Celsius.
A system in which air is heated, cooled, and mixed with fresh “new” air and distributed from a central location through ducts.
A system by which the timing and temperature of the operation of individual zonal heaters can be controlled in a central location. Also see zonal heating.
Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). See Superfund.
See chlorofluorocarbon.
See cubic feet per minute.
Firm capacity (CF) rate. See rates.
See cubic feet per second.
Each of the specific bands of frequencies within an information system assigned for a particular use. In a voice communication system, the band of frequencies that might be assigned as a signaling channel, tone channel, or voice channel.
The current that flows in the capacitance of a transmission line or cable when voltage is applied at its energized terminals.
A manufactured gas used in refrigeration, air conditioning, packaging, solvents, propellant in spray cans, and insulation. Reduces ozone in the upper atmosphere.
A system of conductors through which an electric current is intended to flow; sometimes normally open paths that do not ordinarily conduct in a network can also be considered part of a circuit.
To place two separate electrical circuits (for alternating current, each circuit consists of three separate conductors or bun- dles of conductors) on the same transmission structures.
To place one electrical circuit that consists of three separate conductors or bundles of conductors on one tower.
A switching device capable of making, carrying, and interrupting currents under normal circuit conditions and also making, carrying for a specified time, and interrupting currents under abnormal circuit conditions such as those under faults or short circuits. The medium in which circuit interruption is performed may be designated, as in oil circuit breaker, air-blast circuit breaker, gas or sulfur hexafluoride circuit breaker, or vacuum circuit breaker.
The total length in miles of separate circuits or transmission lines; one circuit mile equals 1.6 circuit kilometers.
A line protective device that interrupts momentary line faults.
A self-controlled device for automatically interrupting and reclosing a circuit, with a predetermined sequence of opening and closing. Usually self-contained in that it includes protective overcurrent relays and control circuitry; available for system operating voltages up to 25 kV.
A relay scheme to reclose a circuit automatically, one time only, after it has been tripped by protective relays; if the circuit trips out after reclosing, it is locked out and prevented from any additional reclosing operations.
A switching device that has limited fault interrupting capability (a load interrupter has no fault interrupting capability); used to switch shunt reactors, shunt capacitor banks, and some transformer banks on customer service substations.
1) A 1963 Federal law, amended several times since, giving the Federal government powers to limit air pollution. 2) A term loosely applied to the Air Quality Act of 1967, which gave the Federal government a stronger regulatory role. An especially important effect was the development of standards based on concentrations of pollutants in air.
A Federal law intended to restore and maintain the chemical, physical, and biological integrity of the nation’s waters and secure water quality that provides for the protection and propagation of fish, shellfish, and wildlife, as well as for recreation in and on the water.
A formal, scheduled and recorded permission for construction, test, and/or maintenance crews to work on particular transmission lines or components within the BPA system. Issued by a dispatcher at a system control center, coordinated with switching schedules to assure equipment is de-energized and safe during maintenance.
1) The distances required between conductors of various voltages and the ground. 2) The distance required between the line and trees, buildings, and other objects on, above or immediately adjacent to the right-of-way.
As used in a power system, the total time from the beginning of an overcurrent condition to the interruption and clearing of the circuit.
Relative to the Pacific Northwest, one of three zones based on the number of heating degree days (HDDs); the three zones are: Zone 1: less than 6,000 HDDs; Zone 2: 6,000-8,000 HDDs; Zone 3: over 8,000 HDDs (western Montana and the severe higher elevations throughout the region).
In a circuit breaker or other switching device, the state when the switch contacts are together, the switch is “on,” and current has a flow path.
Circuitry that prevents the closing of a switching device (circuit breaker, disconnect switch) until certain prescribed conditions exist.
Lands and waters adjacent to the coast that exert an influence on, or are affected by, the uses of the sea and its ecology.
A land use plan required by the Federal government in coastal States, to preserve, develop, and enhance land and water resources of the nation’s coastal zones.
A cable, primarily used for the transmission of high-frequency signals, in which one conductor is centered inside a metallic sheath that serves as a second conductor.
See U.S. Army Corps of Engineers.
The sequential production of more than one form of energy such as heat and mechanical energy, or heat and electricity, or mechanical energy and electricity.
1) One or more wound insulated conductors arranged to produce an electromagnetic force, used in relays and rotating electrical machinery in power systems. 2) Devices that provide inductances in electronic and power systems.
In BPA power sales, the ratio between a customer’s (or customer class’) monthly peak electricity demand and that customer’s (or customer class’) peak demand during the highest monthly demand placed on the entire electrical system. Used for billing purposes and for allocation of costs.
See demand.
See demand.
See Columbia River Basin.
A group of representatives from State and Federal fish and wildlife agencies and Indian tribes in the Northwest who review, advise, and help BPA establish funding priorities for projects that fit the Northwest Power Planning Council’s Columbia Basin Fish and Wildlife Program.
A Northwest Power Planning Council program mandated by the Pacific Northwest Electric Power Planning and Conservation Act and published periodically as a guide for activities in the Columbia River Basin to be carried out by State and Federal agencies to aid fish and wildlife affected by Columbia River dams. Funded, in large part, by BPA power sales.
The development of dams and irrigation projects in eastern Washington by the Bureau of Reclamation, begun in 1934. The project's key feature is Grand Coulee Dam.
The fourth largest river in North America; 2040 kilometers (1,270 miles) long and making a steep descent, dropping from elevation 810 meters (2,650 feet) at its source in British Columbia’s Rocky Mountains down to sea level at Astoria, Oregon.
The land area drained by the Columbia River and its tributaries; its principal boundaries are the Rocky Mountains to the east and north, the Cascade Range on the west, and the Great Basin to the south. Also called the Columbia Basin.
Formed in 1977 by resolution of the Yakima, Warm Springs, Umatilla and Nez Perce tribes, (the tribes that signed treaties in 1855 securing certain fishing rights), the commission supplies technical expertise and enforcement resources to the region.
The Federal and non-Federal dams and reservoirs on the Columbia River and its tributaries.
The 1964 U.S. treaty with Canada for joint development of the upper Columbia River Basin for power benefits and flood control. Canada built three large storage dams —Duncan, Keenleyside, and Mica in British Columbia. The U.S. built Libby Dam in Montana, with its reservoir extending 67 kilometers (42 miles) into Canada.
A nonprofit corporation formed by U.S. public utility districts, municipalities, and private utilities to purchase Canada’s share of power accruing to U.S. power plants as a result of the Columbia River Treaty storage dams.
The use of a combustion turbine and a steam turbine in an electrical generation plant so that the waste heat from the combustion cycle provides heat energy for the steam cycle to increase its efficiency.
See turbine.
A hinged bolted fitting that attaches to the conductor to permit pulling or snubbing without damage to the conductor.
Time provided for the public to review and comment on BPA studies or proposed actions.
See sector.
1) Generally, the process of performing a sequence of switching operations. 2) In a power system, when converting alternating to direct current, a switching process that switches alternating current phases on and off in a way that provides the desired level of direct-current flow.
The use of devices such as capacitors or voltage regulators to improve performance of an electric system with respect to some specified characteristic. The use of such devices to increase capacity.
BPA’s process of soliciting and selecting conservation and generating resources from customers and non-customers for long-term use by means of systematic criteria. Used to acquire new energy resources.
An approach used by utilities similar to BPA’s competitive acquisition approach, but bidding programs are typically regulated by local utility commissions and often characterized by fixed-price bidding.
In law, the first or initiatory pleading on the part of a plaintiff stating the cause of action against the defendant.
For the residential exchange, a review by BPA to determine whether a utility is conforming to the Pacific Northwest Electric Planning and Conservation Act, and the residential exchange agreement certification, and is passing benefits through to consumers.
The average retail rates calculated for all publicly owned and investor-owned utilities in the Pacific Northwest.
See Superfund.
A steel die for pressing compression fittings onto conductor, used with a hydraulic press and specially designed for each size fitting.
A series of fittings, usually consisting of a steel inner piece and aluminum outer sleeve, designed to be compressed on the conductor to permit making connections as required. Examples are variously known as dead-end fittings, splice connectors, and jumper terminals.
1) Additional capacity or energy needed by the customer to meet load over that provided by the customer’s own resources. 2) As applied to BPA customers, the largest amount by which a customer’s entire firm load requirements for a month exceed the assured resources available to it from sources other than BPA.
A purchasing basis, composed of three types: actual computed, contracted computed, or planned computed.
BPA's obligation to supply the customer’s net requirements (difference between actual firm loads and assured capability). May be subject to an availability charge.
contracted computed requirements
The customer contracts for an amount of power less than the difference between its firm loads and its assured resources. The customer is responsible to make up the difference between its firm loads plus its own resources and the BPA contracted amount.
BPA is obligated to supply the difference between the customer’s estimated firm load for the next operating year and the assured capability for the customer’s resources. The customer accepts the risk for the actual firm load being different from the firm load estimated.
See generating public utilities and investor-owned utilities.
The use of a computer to design a device or a system, display it on a screen or as a printout, simulate its oper-ation, and provide statistics on its performance.
In environmental usage, the amount of a pollutant in a given volume or mass of air, water, or soil.
In a steam electric plant, a device that condenses steam into water after the steam has gone through the turbine and before it is fed back into the boiler for reuse.
The transfer of heat or cold through a material when there is a difference of temperature between parts of the material.
See electrical conductivity, thermal conductivity.
1) Any metallic material, usually in the form of wire, cable, or bar, suitable for carrying an electric current. 2) The wire cable strung between transmission towers.
A conductor consisting of all-aluminum strands, with code names after flowers. Also see conductor sizes and weights.
A conductor consisting of all-aluminum strands with trapezoidal cross-sections, with code names after Northwest mountains. Also see conductor sizes and weights.
A conductor with a steel core around which aluminum wires are stranded. Common conductor type used by BPA, with code names after birds. Also see conductor sizes and weights.
A conductor with a steel core around which aluminum wires, with trapezoidal cross-sections, are stranded, with code names after Northwest rivers. Also see conductor sizes and weights.
Two or more conductors used per phase; BPA standard construction for 500 kV is a bundle of three conductors per phase. A bundle of four conductors per phase may also be used on 500-kV lines.
Generally, a large conductor with hollow sections in the interior.
A conductor that has been modified to reduce the amount of reflected light from its surface. Used in areas of high viewer sensitivity to reduce visibility of the line.
One conductor used per phase.
A conductor made up of a number of smaller wires, most commonly a core wire and one or more layers of helically formed wires with the direction of each layer reversed.
See phase.
Looking ahead on line (the direction in which the structures are numbered) the left hand conductor is No.1, the center No. 2, and the right hand No. 3.
The distance the conductor droops below a straight line between adjacent points of support.
A specially designed pulley used in stringing conductor. The sheave is temporarily attached to the insulator string and the conductor threaded through it.
All-aluminum conductors (AAC), all-aluminum conductor/trapezoidal wire (AAC/TW), aluminum conductor steel reinforced (ACSR), and aluminum conductor steel reinforced/trapezoidal wire (ACSR/TW). See following tables.
AAC conductors commonly used by BPA bear the names of flowers:
Diameter
Name
Weight
Mass
(inches)
(mm)
(lbs/ft)
(kg/m)
0.593
15.1
Laurel
0.25
0.372
1.300
33.0
Narcissus
1.19
1.771
1.454
36.9
Coreopsis
1.49
2.217
AAC/TW conductors used by BPA bear the names of Northwest mountains:
Diameter
Name
Weight
Mass
(inches)
(mm)
(lbs/ft)
(kg/m)
0.915
23.2
Baker
0.75
1.116
1.000
25.4
Rainier
0.90
1.339
1.100
27.9
Helens
1.07
1.592
1.300
33.0
Hood
1.49
2.217
1.450
36.8
Bachelor
1.88
2.798
1.600
40.6
Jefferson
2.28
3.393
ACSR conductors commonly used by BPA for transmission lines bear the names of birds:
Diameter
Name
Weight
Mass
(inches)
(mm)
(lbs/ft)
(kg/m)
0.563
14.30
Penguin
0.29
0.43
0.642
16.31
Partridge
0.37
0.55
0.783
19.89
Ibis
0.55
0.82
0.806
20.47
Lark
0.62
0.92
0.927
23.55
Dove
0.77
1.15
1.108
28.14
Drake
1.10
1.64
1.140
28.96
Mallard
1.24
1.84
1.302
33.07
Bunting
1.34
1.99
1.345
34.16
Bittern
1.43
2.13
1.382
35.10
Pheasant
1.64
2.44
1.602
40.69
Chukar
2.07
3.08
1.802
45.77
Thrasher
2.53
3.76
ACSR/TW conductors commonly used by BPA for transmission lines bear the names of Northwest rivers:
Diameter
Name
Weight
Mass
(inches)
(mm)
(lbs/ft)
(kg/m)
0.951
24.2
Toutle
0.89
1.324
1.100
27.9
Rogue
1.13
1.682
1.300
33.0
Deschutes
1.61
2.396
The version of BPA’s budget that is presented to the Congress for annual budget hearings before the congressional appropriations subcommittees on energy and water development.
The sum of the continuous ratings of the load-consuming devices connected to a system.
In land acquisition usage, a damage to property arising as a consequence of a taking and/or construction on other lands. In many States, the property owner may be compensated for damage as a consequence of a change in grade of a street that adversely affects access to the property. In condemnation actions, the courts usually have held that an owner may not be compensated for frustration, loss of goodwill, and damages to business that result as a consequence of a taking or construction by the Government.
Synonymous, at BPA, with energy conservation, the reduction of electric energy consumption as a result of increases in the efficiency of production, distribution, and end use.
BPA’s process of acquiring cost-effective energy savings to meet forecasted needs for resources.
See energy conservation measure.
Energy efficiency measures and purchases that contribute to BPA meeting its load obligations. Conservation resources save energy in the production, distribution, and more efficient use of energy.
A mechanism by which BPA transfers energy to a utility in need of it from a utility that has surplus capacity due to energy conservation.
See real dollars.
An ultimate user of electricity for specific purposes such as heating, lighting, running equipment. May or may not be identical with party billed by a utility (for example, a commercial building owner may be billed for electricity use in a single building with many independent shops). Also referred to as end user. Also see customer.
See sector.
A device, operated other than by hand, for repeatedly establishing and interrupting a low voltage (600 volts or less) circuit under normal conditions.
Any substance or matter that has an adverse effect on air, water, or soil. Also see pollutant.
In a power system, the possibility of a fault or equipment failure. First contingency disturbances (outages) involve only one system element, such as a transmission line fault or a transformer failure. A second contingency disturbance would have one system element out of service and subject the system to a fault and loss of a second element.
The amount of power and transmission service (in kilowatts) that a supplier of electric service agrees to make continuously available for delivery to a particular consumer and that the consumer agrees to purchase.
contracted computed requirements
See computed requirements.
For purposes of the residential exchange, a utility’s exchangeable production and transmission related costs, including purchases and conservation measures, except for costs excluded by section 5(c)(7) of the Pacific Northwest Electric Power Planning and Conservation Act.
For purposes of the residential exchange, the firm energy load used to establish a utility’s retail rates, adjusted using the average system cost methodology.
A legal obligation assumed in a contract that would not exist in the absence of the contract.
control and instrument cable
See cable.
A part of a power system or a combination of systems to which a common generation control scheme is applied to match generation and load.
The facility from which a power system is monitored and regulated. Dispatchers use computerized displays to match generation with load and to respond to faults in the system. BPA has two control centers—at Vancouver and at Moses Lake both in Washington.
A hydroelectric plant that utilizes streamflow only once as it passes downstream, as opposed to a pumped-storage hydroelectric plant.
A device that changes alternating current to direct current or vice versa, or changes one frequency to another.
The assemblage of equipment used to convert alternating current to direct current or vice versa in a power system.
See degree day.
A constructed pond used to receive and dissipate waste heat, usually from a steam-electric plant. Approximately an acre of pond surface is needed per megawatt of electric output for a modern steam-electric plant.
A structure that helps remove heat from water that is used as a coolant, such as in electric power generating plants. In a wet cooling tower, air is moved across a large, continually wetted surface or through a spray of water to achieve the cooling effect.
The atmospheric release of water from cooling towers, sometimes leading to fog and icing, usually in the immediate vicinity of the cooling tower.
A private, nonprofit utility, owned by its members or consumers and operated within State law but essentially self-regulated by a board of directors elected from its membership. Cooperatives are preference customers of BPA.
As applied to hydro plants, the operation of a group of hydro plants and storage reservoirs so as to obtain optimum power benefits with due consideration to other uses, such as navigation, irrigation, recreation, flood control, and fish conservation. Commonly called coordination.
See coordinated operation.
See Pacific Northwest Coordination Agreement.
A luminous electrical discharge due to the ionization of the air surrounding a conductor caused by a voltage gradient exceeding a certain critical value. Can be seen as bluish tufts or streamers surrounding the conductor or conductor hardware, and generally a hissing sound can be heard. Transmission line corona varies with atmospheric conditions and is more intense during wet weather.
A metal ring attached near the conductor end of a string of insulators at 345 kV and higher voltages to reduce electrical discharges called corona. Shields the hardware and insulators, preventing discharge by lowering potential gradients, thereby reducing loss and radio and TV interference. Also known as grading ring.
Corps of Engineers, or Corps
See U.S. Army Corps of Engineers.
A strip of land, 0.8 kilometers (one-half mile) or more wide, forming a passageway for transportation or utility facilities. Also see right-of-way.
A corridor occupied by more than one type of utility or transportation system such as pipelines, transmission lines, communication lines, highways, or railroads.
See cost of service analysis.
An analytical approach to solving problems of choice in which alternatives are quantitatively analyzed to determine the alternative that yields the greatest benefits for any given cost, or yields a specified chosen amount of benefits for the least cost.
1) Generally, a specific objective reached at the lowest total cost. 2) According to the Pacific Northwest Electric Power Planning and Conservation Act, a measure or resource whose estimated incremental system cost is no greater than that of the least-cost similarly reliable and available alternative or combination of alternatives.
Cost of energy that is lost. See losses.
A pricing concept, traditionally used as the primary basis for designing electric rate schedules, that quantifies utility costs and projects revenues to the service provided to each customer class.
A utility or BPA study designed to determine the cost of providing service to various classes of customers. Performed by most utilities under generally accepted ratemaking principles and used by BPA as a starting point for rate design.
1) The obligation to set rates to recover all of BPA’s costs, including repayment of the Federal investment in the Federal Columbia River Power System over a reasonable number of years. 2) A legal process by which potentially responsible parties who contributed to contamination at a Superfund site can be required to reimburse the fund for money spent during any cleanup actions by the Federal government.
A rate adjustment mechanism to better assure the recovery of BPA’s total costs. Not currently included in BPA rates.
Also see expenses, levelized costs, present value costs.
The cost of a utility's generation and transmission system. Under the Residential Exchange provisions of the Northwest Power Act, a utility may sell power to BPA at the utility's average system cost and purchases the same amount of power back from BPA at the priority firm rate.
1) The costs an electric utility would otherwise incur to generate power if it did not purchase electricity from another source. 2) An investment guideline, describing the value of conservation and generation resource investments in terms of the cost of more expensive resources that would otherwise have to be acquired. Also see avoided cost methodology.
capital costs
In the utility industry, the money needed to construct a plant, including the costs of materials, permits, and interest on borrowing; same as capital investment in new resources.
The cost that a utility could avoid by not operating a power plant. A utility’s decremental cost is considered by some regulators to be a fair rate for the utility to pay for purchased power.
Costs readily identifiable or obviously traceable to a specified program, project, or other cost objective.
Estimated expenditures that can be avoided or eliminated without violating: reliability standards, legal contracts, Civil Service regulations, or Federal or State laws.
Capital investment already made (spent).
1) In accounting, operating expenses that do not vary with volume of activity or output, at least in the short run. 2) At BPA, operating expenses that stay basically constant, regardless of power output and even when no electric service is provided to customers. Includes interest expense on the Federal investment in the Pacific Northwest power system, contractual obligations, net costs of the residential exchange, and depreciation expense for long-lived assets.
The computed cost of producing power that accounts for all input costs, including all capital costs, fixed costs, variable costs, direct and indirect costs, and opportunity costs.
In the utility industry, the additional costs that a utility would incur by operating a power plant, the cost of the next kilowatthour generated or purchased, or the cost of producing and/or transporting the next available unit of electrical energy above the current base cost previously determined.
Any costs incurred for common objectives that cannot be directly charged to any single point of cost application.
The cost of producing the next unit of power to be generated.
Those estimated expenditures necessary to meet given reliability standards; carry out legal contracts; comply with Civil Service regulations; or comply with other Federal or State laws; although non-discretionary costs cannot ultimately be avoided, some could be postponed or deferred which puts them, in a short-term sense, in a discretionary category.
The net cost of a forgone opportunity, taking into account the benefits and costs of both the opportunity seized and the opportunity forgone for the period of analysis.
Obligations incurred for goods and services consumed or used in order to accomplish BPA program objectives.
1) Generally, all costs associated with a resource including its costs and the costs of other resources affected when the resource is included in the utility system. 2) According to the Pacific Northwest Electric Power Planning and Conservation Act, all direct costs of a conservation or generation resource over its effective life, including, if applicable, distribution and transmission, waste disposal, end-of-cycle, and fuel costs (including projected increases) and quantifiable environmental measures.
1) In accounting, costs that fluctuate in relation to changes in output or activity level. 2) In regard to a generating resource, the total costs incurred to produce energy, excluding fixed costs, which are incurred regardless of whether the resource is operating.
See California/Oregon Transmission Project.
Unit of electric charge. The quantity of electric charge that passes a point on the conductor in one second when the current is one ampere.
See Northwest Power Planning Council.
See Northwest Conservation and Electric Power Plan.
A buried wire system connected to the footings of towers or poles supporting a trans-mission line. Used to establish a low resistance path to earth, usually for lightning protection.
The meeting of contractual power obligations by offsetting one schedule against another; 100 MW scheduled north to south, and 50 MW scheduled south to north, are combined for a real schedule of 50 MW north to south.
1) In general, the association of two or more transmission lines or equipment components in such a manner that power is transferred from one to the other. 2) On a signal transmission system, the effect of an interfering source.
See cost recovery adjustment clause.
Air pollutants having National Ambient Air Quality Standards.
The smallest mass of fissionable material that will support a self-sustaining chain reaction under stated conditions.
The portion of the historical streamflow record for the Columbia River System during which the least amount of electrical energy can be generated by drafting the reservoirs according to seasonal demands. A fundamental planning concept used to determine annual firm energy load carrying capacity for the hydro system.
In resource planning, the average amount of energy projected to be generated during a period (which can vary in length depending on the purpose of the planning) of extremely low streamflow.
The water levels in reservoirs that must be maintained to ensure firm energy requirements can be met under the most adverse historical streamflow conditions. Critical rule curves are used to guide reservoir operation for power generation.
Any fish stocks that are substantially diminishing, and for which harvest and production management actions reflect the stock’s critical condition.
See critical water.
A sequence of streamflows under which the regional hydro system could produce an amount of power equal to that which could have been produced during the historical critical period, given today’s generating facilities and constraints.
Planning that prepares to meet firm loads under the worst streamflow conditions on record.
The crossing members of a wood pole or steel tower that support the insulators for the conductor.
The placement of two vent openings so that air flows in one vent, over the insulated space, and out the other vent due to wind or thermal convection.
The study and design of devices using properties of certain materials at near-absolute zero temperature (-273°C, or -460°F), such as superconductivity, or ability to carry an electric current with near zero resistance.
See Columbia Storage Power Exchange.
Combustion turbine. See turbine.
CT
Current transformer. See transformer.
A unit of measurement for the flow rate of air or water. Specifically used as an air exchange rate with regard to indoor air and refers to the amount of air, in cubic feet, that is exchanged. One cfm converts to 0.00047 cubic meters per second.
A measurement of water flow past a given point. One cfs is equal to approximately 449 gallons per minute. One cfs converts to 0.0283 cubic meters per second.
Any nonrenewable evidence of human occupation or activity as seen in any district, site, building, structure, artifact, ruin, object, work of art, architecture, or natural feature that was important in human history.
The basic unit to describe the intensity of radioactivity, equal to 3.7 x 1010 disintegrations per second, which is approximately the rate of decay of 1 gram of radium. Named for Marie and Pierre Curie, who discovered radium in 1898; one curie = 3.7 x 1010 becquerel.
1) In common usage, the flow of electric energy when an appliance or machine is turned on. 2) In technical sense, a term usually modified by an adjective, such as direct current, referring to the rate of electrical charge flowing through a conductor or circuit as compared to voltage (volts), which is the force or pressure that causes the current to flow; current and ampere are often used interchangeably.
current diversion (or energy diversion)
The theft of electric power by diverting current to bypass the meter. More generally, any type of tampering to obtain unmetered service.
See transformer.
A temporary reduction in electric power delivery under emergency conditions, taken after all possible conservation and load management measures have been tried, and prompted by problems in meeting minimum requirements, rather than peaking deficiencies.
A utility, large industry, or Federal agency that buys power or transmission services directly from BPA. See consumer.
A group of BPA customers with similar characteristics that are identified for the purpose of setting a rate for electric service. BPA customer classes are preference customers (public utility districts, cooperatives, municipalities), direct-service industrial customers, Federal agency customers, and investor-owned utilities.
See trust fund.
The statement of policy, guidelines, and criteria for all transmission facilities BPA will provide to deliver energy over BPA’s grid to a customer, including transmission lines, transmission taps, and transformer additions, as well as distribution substations. Also covers wheeling and participation in emergency operations should a customer suffer a transformer failure.
See Clean Water Act.
See categorical exclusion.
A complete sequence of a wave pattern that recurs at regular intervals, as in one complete set of positive and negative values of an alternating current or voltage. The number of cycles occurring in one second is the frequency of the wave (for example. A frequency of 60 Hz has 60 complete cycles occurring in one second).
See reservoir.
See Coastal Zone Management Plan.
 
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