Relevant terminology
Air emissions/air quality - The Clean Air Act directs the EPA to establish air quality standards to protect public health and the environment. The EPA sets national air quality standards for six principal air pollutants (also called the criteria pollutants): nitrogen dioxide (NO2), ozone (O3), sulfur dioxide (SO2), particulate matter (PM), carbon monoxide (CO), and lead (Pb).
Baseload capacity - The generating equipment normally operated to serve loads on an around-the-clock basis.
Baseload plant - This is the kind of generating plant that provides the basic power that is needed year round. A baseload plant is designed to run 24 hours per day and most of the hours of the year.
Bituminous coal - The coal ranked below anthracite. It generally has a high heat content and is soft enough to be readily ground for easy combustion. Bituminous accounts for the bulk of all coal mined in the United States.
Boiler - A device for generating steam for power, processing, or heating purposes or for producing hot water for heating purposes or hot water supply. Heat from an external combustion source is transmitted to a fluid contained within the tubes in the boiler shell. This fluid is delivered to an end-use at a desired pressure, temperature, and quality.
Bottom ash - Slag or other residue remaining in the boiler after coal is burned.
British thermal unit (Btu) - The amount of heat necessary to raise the temperature of one pound of water, one degree Fahrenheit.
Bulk power - Large amount of electricity. It is transported over high-voltage transmission lines.
Bus - An electrical conductor which serves as a common connection for two or more electrical circuits.
Bus bar - Large rigid, bar shaped or tubular conductors that are used to form a bus arrangement.
Bus-bar cost - The total cost of generating electricity, not including substation and transmission losses.
Capability - The maximum load that a generating unit, generating station, or other electrical apparatus can carry under specified conditions for a given period of time without exceeding approved limits of temperature and stress.
Capability, net - The maximum load-carrying ability of the equipment, exclusive of station use, under specified conditions for a given time interval, independent of the characteristics of the load. (Capability is determined by design characteristics, physical conditions, adequacy of prime mover, temperature, headwater and tailwater elevations, and electrical use.)
Capability, net summer - The steady hourly output, which generating equipment is expected to supply to system load exclusive of auxiliary power, as demonstrated by tests at the time of summer peak demand.
Capability, net winter - The steady hourly output which generating equipment is expected to supply to system load exclusive of auxiliary power, as demonstrated by tests at the time of winter peak demand.
Capacity - The amount of electric power delivered or required for which a generator, turbine, transformer, transmission circuit, apparatus, station, or system is rated by the manufacturer. Capacity is also used synonymously with capability.
Capital expenditures - Construction costs of new utility plants. These include costs of plant additions, improvements, and replacements, as well as expenditures for the purchase or acquisition of existing utility plant facilities.
Capital intensive - Having a high assets to sales ratio. Utilities often have $3 to $4 of assets for every $1 of sales while another manufacturer may have only 80 cents of assets for every $1 of sales.
Certificate of Need (CON) - This is a first step in the process of permitting a transmission line in Minnesota.
Circuit - The path of electric current from the power source, through the conductors, through the device using the power, back through the conductors, and back to the source of power. The two types of circuits are:
. Series circuit - A circuit in which electricity has only one path.
. Parallel circuit - A circuit in which electricity has multiple paths.
Circuit breaker - A time-delay circuit interrupter, which opens the circuit when the current flow exceeds the breaker/rating for a short period of time.
Circuit recloser - A device that protects electric lines by momentarily interrupting service when a fault occurs, then restoring power automatically when the fault is cleared. This keeps outages from occurring when temporary problems happen, like branches touching a line.
Clean Air Act - A national law passed in 1963 and amended several times since, giving the U.S. Government broad powers to limit air pollution.
Coal-fired generation - Generation from a power plant that uses coal as the main fuel source.
Coal gasification - The conversion of coal to a gas that is suitable for use as a fuel.
Combined cycle - An electric generating technology in which electricity is produced from otherwise lost waste heat exiting from one or more gas (combustion) turbines. The exiting heat is routed to a conventional boiler or to a heat recovery steam generator for utilization by a steam turbine in the production of electricity. This process increases the efficiency of the electric generating unit.
Combined cycle unit - An electric generating unit that consists of one or more combustion turbines and one or more boilers with a portion of the required energy input to the boiler(s) provided by the exhaust gas of the combustion turbine(s).
Conductor - A material that allows an electric current to pass through it. Also, the wire that carries electricity in an electric distribution or transmission system.
Cooperative electric utility - A system in which consumers of electricity own their own distribution system, which in turn owns the wholesale power supplier.
Current - The flow of electrons through a conductor.
Cycle - In alternating current, the current goes from zero voltage to a maximum in one direction, back to zero and then to maximum in the other direction and back to zero again constituting a cycle.
Delivery point - The point, usually a substation, to which electricity is transmitted from its generating sources.
Demand - The amount of electricity a customer takes at any given moment (varies from hour to hour, day to day, and season to season). This usage, which is expressed in kilowatts (not in kilowatt-hours), is called the "demand" on the system. Seasonal demands are affected by the number of hours of daylight, temperature extremes, and activities such as agricultural processes. These are four different types:
. Billing demand - The demand, which is used to determine the demand charges in accordance with the provisions of a rate schedule or contract.
. Coincident demand - Any demand that occurs simultaneously with any other demand; also, the sum of any set of coincident demands. Refers to the maximum demand which occurs at a specific time. For example, it may represent a distribution system's demand at the time of its power supplier's peak or an individual consumer's demand at the time of his respective substation peak. The coincident demands are normally used in cost-of-service studies to allocate demand-related costs to consumer categories.
. Maximum demand - The greatest of all demands of the load that has occurred within a specified period of time.
. Non-coincident demand - The highest demand over any given time frame, usually a month or a year, without regard to any other system's demand.
Dispatching - The operating control of an integrated electric system involving such operations as the assignment of load to specific generating stations to result in the most reliable and economical use of fuel supply. Also, the control of operations and maintenance of high voltage lines, substations and equipment, the operation of principal tie lines and switching, and the schedule of energy transactions with other connecting electric utilities.
Dispersed generation - Small, decentralized generators such as diesel or combustion turbines, designed to supplement or replace power generated at large generating plants. Typically located at or near the point of use.
Distribution - That part of an electrical system that delivers power from a substation to the end user (customer). May include substations.
Distribution cooperative - An electric cooperative that purchases wholesale power and delivers it to member-owners.
Distribution lines - The conductors that deliver power from the substation to the service transformers. May be either overhead or underground.
Distribution system - That portion of a power system that functions to deliver power from a substation to the end user (customer). Typically consists of both overhead and underground components and may include substations.
Easement - A right purchased from property owner(s) that allows utility companies to construct, operate, maintain and control facilities, such as transmission lines, on the property
Economic dispatch - Determines the share of the minute-by-minute load demand that each committed unit has, so that the overall system operating cost is minimized.
Economies of scale - A condition achieved when costs are reduced due to operation or output at a higher volume. For services, there may be economies of scale in delivering to a larger number of customers, allowing fixed costs to be spread over a larger number.
Edison Electric Institute (EEI) - EEI members include investor-owned electric power companies and electric utility holding companies. Focuses on economics, industrial relations, and statistics of the electric industry. Acts as liaison with the federal government in all areas of electric utility operation and concern. Publications available. Library open to public by appointment.
Efficiency - Making maximum use of a resource. Requires less sacrifice than conservation, but stresses getting the most benefit out of each unit of a resource used.
Electric cooperative - A non-profit, member-owned electric utility company. Some cooperatives are only generation and transmission. As with other co-op businesses, any margin is returned to the consumers according to the amount of business conducted with the co-op.
Electric current - The flow of electrons in a conductor between two points having a difference in potential, generally expressed in amperes.
Electric energy - As commonly used in the electric utility industry, the use of power over time, commonly measured in kilowatt-hours.
Electric Power Research Institute (EPRI) - A non-profit, research organization financed by electric utilities for the purposes of research and development of energy resources.
Electric utility - A corporation, person, agency or other legal entity or instrumentality that owns and/or operates facilities within the United States, its territories or Puerto Rico for the generation, transmission, distribution or sale of electric energy primarily for use by the public and files forms listed in the Code of Federal Regulations, Title 18, Part 141. Facilities that qualify as co generators or small power producers under the Public Utility Regulatory Policies Act (PURPA) are not considered electric utilities.
Electromagnetic fields (EMFs) - Electric and magnetic fields often occur together, hence the term electromagnetic fields. They are found throughout nature and can be grouped by wavelength or frequency. The counterparts have the following definitions:
. Electric fields - Created by voltage. Anytime something electric is plugged in it has an electric field, even if it is not in use. An electric field, in some instances, can be felt when the hair on your neck stands up during a lightning storm, for example. An electric field can be blocked by trees, walls, or buildings.
. Magnetic fields - Created by current. Anything that carries electricity (such as power lines) and anything that uses electricity (such as home appliances in use) has a magnetic field. A magnetic field cannot be felt, and it passes through most objects.
Electrostatic precipitator - An electronic pollution control device that removes particles of fly ash from a power plant's waste gases. The device first charges particles in the gas stream and then collects them on an oppositely charged surface.
Eminent domain - The power of a government body to condemn and use private property for public use with just compensation to the property owner.
Energy - The capacity for doing work; may be natural or manufactured. Electrical energy is usually measured in kilowatt-hours.
Energy source - The primary source that provides the power that is converted to electricity through chemical, mechanical, or other means. Energy sources include coal, petroleum and petroleum products, gas, water, uranium, wind, sunlight, geothermal and other sources.
Environmental impact statement (EIS) - A statement based on a detailed study that sets forth the probable environmental consequences of building and operating large-scale facilities.
Environmental Protection Agency (EPA) - A federal agency that develops rules and regulations concerning environmental protection and monitors utilities and other industries.
EPACT - The Energy Policy Act of 2005. For more information visit this page.
EPRI - Electric Power Research Institute, an organization financed by electric utilities for the purposes of research and development of energy resources.
Federal Energy Regulatory Commission (FERC) - In October 1977, FERC succeeded the Federal Power Commission (FPC) as the agency that sets and enforces the wholesale electric rates that investor-owned utilities charge rural electric cooperatives and other wholesale customers. The agency also licenses hydroelectric projects. It is a five-member board that is part of, but independent of, the DOE. Via the Energy Policy Act of 1992, it also has been charged with the responsibility to make the electric energy industry more market oriented as opposed to the long-standing monopoly orientation.
Flue gas - The mixture of gases and fly ash escaping from a coal fired boiler.
Flue gas desulfurization unit (scrubber) - Equipment used to remove sulfur oxides from the combustion gases of a boiler plant before discharge to the atmosphere. Chemicals, such as lime, are used as the scrubbing media.
Flue gas particulate collectors - Equipment used to remove fly ash from the combustion gases of a boiler plant before discharge to the atmosphere. Particulate collectors include electrostatic precipitators, mechanical collectors (cyclones), fabric filters (baghouses) and wet scrubbers.
Fluidized-bed combustion - A method of burning coal to achieve lower emissions by combining coal with limestone or other similar material held in suspension by air moving upward through the boiler.
Fly ash - Tiny particles of solid ash in smoke when fuels (such as coal) are burned.
Forced outage - The period of time during which a power plant is scheduled to operate but is unable to do so because of breakdowns or other unforeseen circumstances.
Fossil fuel - Materials such as coal, oil, and natural gas which are also called conventional fuels. Alternatives include hydro (water), solar (sun), nuclear, wind, geothermal (derived from heat contained deep inside the earth) and other energy sources.
Fossil fuel plant - A plant using coal, petroleum, or gas as its source of energy.
Gas turbine - An electric generating station where the generator is driven by a gas turbine engine.
Generating unit - Any combination of physically connected generator(s), reactor(s), boiler(s), combustion turbine(s), or other prime mover(s) operated together to produce electric power.
Generation - Producing electricity by power plant or machine.
Generation company (Genco) - An entity that operates electricity generating plants. The Genco may own the generation plants or interact with short-term marketers on behalf of plant owners.
Generation, gross - The total amount of electric energy produced by the generating units at a generating station or stations, measured at the generator terminals.
Generation, net - Gross generation less the kilowatt-hours consumed to operate the generating station.
Generation station (power plant) - A plant that has generators and other equipment for producing electricity.
Generation & Transmission Cooperative (G&T) - A cooperative, which generates electricity and transmits it to distribution cooperatives.
Generator - A machine that transforms the mechanical energy of a rotating shaft to electric energy.
Global warming - A gradual warming of Earth's atmosphere reportedly caused by the burning of fossil fuels and industrial pollutants.
Green power - A term, which refers to production of electricity using renewable sources such as wind, hydroelectric or crop residue.
Greenhouse effect - A global warming trend caused by the trapping of heat in Earth's atmosphere due to rising amounts of carbon dioxide and other gases.
Greenhouse gases - Carbon dioxide and other gases that reportedly contribute to the warming of the Earth's atmosphere.
Grid - A system of interconnected high-voltage transmission lines and power generating facilities that allows bulk-power suppliers to share resources on a regional basis. This system provides emergency generation and transmission by transmitting power from areas having a surplus to areas experiencing a shortage. The creation of a national grid has been proposed.
H-frame - A structure used in transmission lines composed of two poles connected by a cross arm near the top.
IBEW - International Brotherhood of Electric Workers.
IEEE - Institute of Electrical and Electronic Engineers, Inc.
Incremental cost - The incremental cost (or marginal cost) represents the cost of an additional unit. This may be an additional residential consumer or an additional load.
Independent power producer (IPP) - A private entity that generates electricity and sells it to other businesses, including utilities.
Independent system operator (ISO) - The independent operator of a transmission system, responsible for guaranteeing open access, scheduling, system reliability and accounting.
Independent Transmission Company (ITC) - A for-profit company that owns transmission assets through, for example, divestiture or long term leasing. Another form of a regional transmission organization.
Institute of Electrical and Electronics Engineers, Inc. (IEEE) - Develops standards on definitions, test methods, symbols, units and safety in the field of electrical science and engineering.
Insulator - A nonconductor, usually of glass, porcelain, or polymer, for insulating and supporting electric wires.
Interconnection agreement - A three party agreement between the generator, the transmission provider, and the transmission owner in the MISO region that defines the accountably of each party and allows the generator to connect to the transmission system.
Integrated gasification combined cycle (IGCC) - A developing clean coal technology that turns coal into a gas and then removes impurities from the coal gas before it is combusted.
Investor-owned utility (IOU) - Utilities that generate and distribute electrical energy for a profit.
Kilovolt (kV) - One kilovolt is equal to 1,000 volts. The amount of electric force carried through a high-voltage transmission line is measured in kilovolts. The standard voltage for use in the home is 120 volts. For long transmission purposes, the voltages go as high as 1,000,000 volts. (1,000 kV)
Least-cost planning - Efforts by utilities and regulators to meet growing power needs without building new plants. Methods include buying power from other utilities, making maximum use of transmission grids and developing conservation programs.
Lignite - A low-sulfur, low-energy coal, found primarily in the upper Great Plains.
Line loss - Electrical energy lost in the process of transmitting over power lines.
Load - The amount of power drawn from an electric system at a specific time, or the total power drawn from the system. Peak load is the amount of power drawn at the time of highest demand. Also, anything that uses electrical energy.
Load curve - A graph used to show how the use of electricity rises and falls during a given period of time.
Load diversity - The variation in electric usage among customers in a given area over a given time. Since not all users consume their maximum amount at the same time, there is diversity.
Load factor - The ratio of average demand/load to peak demand/load. A high load factor is better than a low load factor because it means the electrical system is being used closer to its full capacity at all times.
Load forecasting - Predicting a system's load and kilowatt-hour sales growth.
Losses - Power (kilowatts) and energy (kilowatt-hours) lost during the operation of an electric system. Losses occur principally when energy is transformed into wasted heat in conductors and other apparatus
MAPP - Mid-Continent Area Power Pool - The Mid-Continent Area Power Pool is an association of electric utilities and other electric industry participants. MAPP was organized in 1972 for the purpose of pooling generation and transmission.
Marginal cost - The change in total costs associated with a unit change in quantity supplied. (i.e. demand or energy)
Marginal cost pricing - A method of determining the selling price of a commodity when the fixed costs are paid by units already sold so that the next units can be sold for less.
Megawatt (MW) - One million watts (1,000 kW).
Megawatt-hour (MWh) - One million watt-hours (1,000 kWh).
Mid-Continent Area Power Pool (MAPP) - An organization of power suppliers in the Upper Midwest that plans for power availability by coordinating power exchanges between members. MAPP's members include investor-owned companies, municipal systems, electric cooperatives and the federal government's Missouri Basin hydroelectric system.
Mid-West Electric Consumers Association - A lobbying and planning organization of more than 340 consumer-owned electric utilities and federal power organizations in the nine-state Missouri River drainage basin, formed to obtain dependable low-cost electric power. Use short form, Mid-West, on second reference; do not use acronym MECA.
MinnElecTrans - MinnElecTrans is a short-hand term used to describe the process under which utilities that own and/or operate electric transmission facilities in Minnesota hold public meetings, prepare and receive information, review and develop facility alternatives and otherwise meet their transmission planning requirements under Minnesota law.
Minnesota Association of Cooperatives (MAC) - A non-profit Minnesota association for cooperatives. Basic goals of MAC are to promote the common interests of cooperatives in legislation, government policy, public understanding and cooperative education, encourage and support farmer marketing, supply and service cooperatives, and encourage and support consumer housing, insurance and credit cooperatives.
MISO - Midwest Independent System Operator - As a fully integrated regional transmission organization, the non-profit Midwest ISO assures industry consumers of unbiased regional grid management and open access to the transmission facilities under Midwest ISO's functional supervision. Midwest ISO optimizes the efficiency of the interconnected system, provides regional solutions to regional planning needs and continually minimizes any risk to reliability.
Municipal electric system - An electric system owned by a town or city.
Natural gas-fired generation - Generation from a power plant that uses natural gas as the main fuel source.
Net capability (capacity) - The maximum load-carrying ability of the equipment, exclusive of station use, under specified conditions for a given time interval, independent of the characteristics of the load. (Capability is determined by design characteristics, physical conditions, adequacy of prime mover, energy supply, and operating limitations such as cooling and circulating water supply and temperature, headwater and tailwater elevations, and electrical use.) Used synonymously with capacity.
Net generation - Gross generation minus plant use from all electric utility owned plants. The energy required for pumping at a pumped-storage plant is regarded as plant use and must be deducted from the gross generation.
North American Electric Reliability Council (NERC) - Formed by the electric utility industry in 1968 to promote the reliability and adequacy of bulk power supply in the electric utility systems of North America. NERC consists of nine Regional Reliability Councils encompassing virtually all of the power systems in the United States and Canada.
Occupational Safety and Health Administration (OSHA) - Department of Labor agency that sets standards for safe work places and enforces them through periodic inspections.
On line - Generally used to indicate when a generating plant is scheduled to be in operation. When an operational plant is not on line, it is said to be "down."
Open transmission access - the ability of a utility to purchase power from another utility or independent power producer and move it over transmission lines that belong to a utility not involved with the purchase, made possible through the Energy Policy Act of 1992.
Participant - In terms of the Big Stone Project, this refers to one or more of the seven owners.
Particulate - Particulate matter is composed of small solid and liquid particles suspended in the ambient air.
Power grid - A network of generation, transmission, and distribution systems that are interconnected.
Power line - A conductor carrying electricity from the generator to the supplier or the ultimate consumer. Two words.
Power pool (electric) - Two or more electric systems which are interconnected and operated on a coordinated basis to achieve economies in supplying their combined loads.
Power supplier (or electric energy supplier) - A company that supplies the actual energy either by generating it or by arranging for its delivery to the consumer.
Public Utilities Commission (PUC) - A Minnesota legislative and quasi-judicial independent regulatory commission responsible for the administration of the Public Utilities Act. The PUC consists of five members who serve six-year terms. Appointments are made by the governor with the advice and consent of the Senate. No more than three of the five commissioners can belong to the same political party, and at least one member must be from outside the seven-county Metro area. There are no specific professional qualifications. The PUC is established in Chapter 216A of Minnesota Statutes.
Public Utilities Holding Company Act (PUHCA) - Federal legislation dating from the Great Depression designed to control corporate activities of investor-owned utilities.
Public Utility Regulatory Policy Act (PURPA) - One of five parts of the National Energy Act passed by Congress on October 15, 1978. It is concerned with voluntary rate standards, cogeneration, small hydro loans, interconnections and wheeling, and other regulatory policies.
Pulverized coal - Coal that is ground to a fine consistency. To learn about a pulverized coal combustion system visit the Energy and Environmental Research Center web site.
Regional Reliability Organization (RRO) - An organization that is charged with ensuring compliance with North American Electric Reliability Council standards and criteria. This organization is responsible for the safety and reliability of a region's bulk electric system.
Regional Transmission Organization (RTO) - A regional organization that oversees transmission in a defined area and ensures access to the transmission grid. There are several models of an RTO, including an Independent System Operator (ISO), which is a non-profit organization that controls, but doesn't own the power lines in its region. Another form of an RTO is an Independent Transmission Company (ITC), a for-profit company that owns transmission assets through, for example, divestiture or long term leasing.
Renewable resources - Naturally, but flow-limited resources that can be replenished. They are virtually inexhaustible in duration but limited in the amount of energy that is available per unit of time. Some (such as geothermal and biomass) may be stock-limited in that stocks are depleted by use, but on a time scale of decades, or perhaps centuries, they can probably be replenished. Renewable energy resources include: biomass, hydro, geothermal, solar and wind. In the future, they could also include the use of ocean thermal, wave, and tidal action technologies. Utility renewable resource applications include bulk electricity generation, on-site electricity generation, distributed electricity generation, non-grid-connected generation, and demand-reduction (energy efficiency) technologies.
Reserve margin (operating) - The amount of unused available capability of an electric power system at peakload for a utility system as a percentage of total capability.
Reserves - The power reserve capacity above firm system load required to provide for: (1) regulations within the hour to cover minute-to-minute variations in demand, (2) load forecasting error, (3) loss of equipment and (4) area protections. It is the reserve capacity capability needed to ensure a specified standard of service.
Right of way - Use of property covered by an agreement that allows utilities to construct and operate their facilities there. Sometimes acquired through the right of eminent domain.
Rural Electric Cooperatives (RECs) - Individual, consumer-owned, non-profit, electric cooperatives are located largely in the rural areas of the country. Rural people joined together to borrow money through the Rural Electrification Act of 1936 to build their own electrical systems and bring central-station electrical service to their farms and homes.
Sag - The distance between the actual location of a conductor (at its lowest point in a given span) and an imaginary line drawn between the conductors two adjacent supports.
Scheduled outage - The shutdown of a generating unit, transmission line, or other facility, for inspection or maintenance, in accordance with an advance schedule.
Scrubbers - Used to clean pollutants from stack gases at power plants that burn fossil fuel.
Spinning reserve - Generating units connected to the bus and ready to take load.
Stakeholder - A stakeholder is any individual or party with a vested interest in the outcome of a debate. Generally, a stakeholder will somehow be impacted by this outcome.
Steam generating station - A conventional generating station where the generator is driven by steam. The steam is generated by the heat produced from the burning fossil fuels.
Stray voltage - Neutral to earth voltage, which is voltage that exists between the system neutral (grounded conductor) and the earth.
Structures - Refers to poles within a given power line.
Sub-bituminous coal - Coal with medium capability of producing heat.
Substation - An electrical facility containing equipment for controlling the flow of electricity from supplier to user. Usually a fenced area containing transformers, voltage regulators, switching, devices, and metering equipment.
Sulfur (S) - An element that appears in many fossil fuels. In combustion of the fuel, the sulfur combines with oxygen to form sulfur dioxide.
Sulfur dioxide (SO2) - One of several forms of sulfur in the air, sulfur dioxide is an air pollutant generated principally from combustion of fuels that contain sulfur (i.e. coal and other fossil fuels).
Supercritical boiler technology - A boiler technology that improves efficiency and brings the benefits of reduced fuel costs, reduced CO2 emissions, and reduced NOx and SO2 emissions.
System demand - The total amount of energy required to supply all consumers.
Transformer - A device used to raise or lower voltage. Transformers are used to increase voltage at the generating plant for transmission to the substation. The substation transformers reduce voltage to distribution level: a distribution transformer reduces the voltage to a utilization level; another transformer may be required to further reduce the voltage for a doorbell.
Transmission - The process of transporting electric energy over long distances to other principal parts of an electric system or to other utility systems for subsequent voltage reduction and distribution.
Transmission grid - An interconnected system of wires and other equipment used to move large amounts of electricity from the generation source to a distribution system.
Transmission line - Poles, towers, structures and conductors used to transmit power from one terminal or station to another.
Transmission system - That system formed by the operation and interconnection of multiple transmission lines.
Utility - A company that provides electricity, water, gas, phone or Internet for residential and commercial use. May or may not be a cooperative entity.
Utility plant - The fixed assets of a utility.
Western Area Power Administration (WAPA) - An agency of the U.S. Department of Energy that markets and delivers reliable, cost-based hydroelectric power and related services within a 15-state region of the central and western U.S. WAPA is one of four power marketing administrations within the U.S. Department of Energy whose role is to market and transmit electricity from multi-use water projects. WAPA's transmission system carries electricity from 57 power plants totaling an operating capacity of 8,785 megawatts.
Wet scrubber - Wet air scrubbers are designed to remove airborne particulates, contaminants, gases and odors from industrial exhaust and chemical processes .
Wheeling - The use of a utility's transmission lines by other power producers.
Wheeling charge - An amount charged to an electric system by another for the transmission of energy to and from another system.
Winter peak - The greatest load on an electric system during a specified demand interval in the winter season, usually between December 1 of a calendar year and March 31 of the next calendar year.
