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Glossary of Terms

 
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alternating current (AC) - an electric flow that reverses its direction at regular recurring intervals. Each forward-backward motion interval is called a cycle. Electric current in the U.S. alternates with a frequency of 60 hertz or cycles per second. (See direct current)
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ampere (AMP) - a unit for measuring the strength of an electric current.
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anode - the positive electrode toward which negative particles (anions, electrons) move within a device such as the cells of a battery, electrolytic cells and diodes.
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atom - the basic component of all matter; the smallest particle of an element that can exist either alone or in combination. Each atom consists of a nucleus (containing neutrons and patrons ) and electrons.
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battery - any energy-storage device allowing release of electricity on demand. It is made up of one or more electrical cells. Primary-cell batteries are disposable; secondary-cell batteries, or accumulators, are rechargeable. Primary-cell batteries are an extremely uneconomical form of energy, since they produce only 2 percent of the power used in their manufacture. The lead-acid car battery is a secondary-cell battery. The car's generator continually recharges the battery. It consists of sets of lead (positive) and lead peroxide (negative) plates in an electrolyte of sulfuric acid (battery acid). The introduction of rechargeable nickel-cadmium batteries has revolutionized portable electronic newsgathering (sound recording, video) and information processing (computing). These batteries offer a stable, short-term source of power free of noise and other electrical hazards.
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bauxite - the raw material mined from the earth we use to make aluminum.
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biodegradable - capable of being broken down by living organisms, principally bacteria and fungi.
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biomass - biomass energy is derived from plants. Alcohol fuels are produced from wood, sugarcane and corn. Firewood, crop residue and cattle dung can also be burned as biomass fuel. As long as the amount of plants regrown equals the amount of fuel burned there will be no additional carbon dioxide produced to contribute toward global warming.
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brownout - the reduction of voltage (and thus power) when demand for electricity exceeds generating capacity.
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BTU - a British Thermal Unit. A measure of energy in the English system measurement, roughly the amount of heat required to raise one pound of water one degree Fahrenheit. This unit of measuring heat has largely been replaced in usage by "joule."
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calorie – former term used for measuring heat which has now been replaced by the term joules (J).
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carbon dioxide (CO2) - a colorless, odorless, nonflammable gas formed during decomposition, combustion and respiration. CO2 is used in food refrigeration (dry ice), carbonated beverages (the bubbles and fizz), fire extinguishers and aerosol cans. Whenever something burns – such as gasoline, wood or a candle – CO2 is produced from the available oxygen combined with the carbon in the fuel.
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carbon monoxide (CO) - colorless, odorless gas formed when carbon is oxidized in a limited supply of air. It is a poisonous constituent of car exhaust fumes, forming a stable compound with hemoglobin in the blood, thus preventing the hemoglobin from transporting oxygen to the body tissues.
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chlorofluorocarbon (CFC) - synthetic chemical that is odorless, nontoxic, nonflammable and chemically inert. CFCs have been used as propellants in aerosol cans, as refrigerants in refrigerators and air conditioners, and in the manufacture of foam packaging. They are partly responsible for the destruction of the ozone layer.
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circuit - the completed path traveled by an electric current.
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circuit breaker - an automatic switch which operates like a fuse and interrupts a circuit under an infrequent abnormal condition.
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coal - coal is a form of stored solar energy. It is created from the remains of plants that have been concentrated by heat and pressure for millions of years. Coal is found in various forms or "grades," which depend on the ratio of carbon mass to energy content. Represented in descending order of hardness and energy content per pound, these grades are anthracite, bituminous, sub-bituminous and lignite.
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cogeneration  - the use of waste heat from an electrical generating plant for other purposes, such as heating. Also, the use of waste heat from a high-temperature industrial process to generate electricity.
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conductor - any material that allows electric current to move through it easily such as copper wire.
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core - the center of a nuclear reactor where the fission process takes place; fissionable fuel and control rods are located in the core.
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crude oil - crude oil is petroleum direct from the ground, prior to refinement or processing.
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cubic foot - a unit of measurement for volume. It represents an area one foot long, by one foot wide, by one foot deep. Natural gas is measured in cubic feet, but the measurements are usually expressed in terms of Bcf, Tcf, Mcf, or Quads.
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demand-side management (DSM) - DSM is the management of the demand for power. It consists of actions undertaken by utilities to influence one’s use of electricity for the benefit of both the user and the utility company. For example, when a utility reaches the point that more capacity is needed, it can either supply more power or reduce demand for electricity through DSM. DSM can include the shifting of demand to off-peak hours, reducing overall consumption, or increasing one’s overall energy efficiency. Many spread their fixed cost over a specified user base, and increase efficiency through economies of scale and load diversity. In return for this franchise, utilities have an "obligation to serve" all users in that territory on demand. This means that utilities must ensure that there are sufficient generation, transmission and distribution systems to serve all their present and future users.
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direct current (DC) - electricity that flows continuously in one direction. (See alternating current)
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distribution - a system of delivering acceptable voltage electricity from transmission lines to individual customers.
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ecology - study of the relationship among organisms and the environments in which they live, including all living and nonliving components.
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efficiency - the amount of work output compared to the quantity of energy input. Efficiency can improve by either increasing the accomplished work or by decreasing the energy expended to accomplish that work. Nothing is 100 percent efficient. An incandescent light bulb is very inefficient as a source of light, yet it is a good source of heat.
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electrodynamics - the branch of physics dealing with electric currents and associated magnetic forces. Quantum electrodynamics (QED) studies the interaction between charged particles and their emission and absorption of electromagnetic radiation. This field combines quantum theory and relatively theory, making accurate predictions about subatomic processes involving charged particles such as electrons and protons.
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electric current - the flow of electronically charged particles through a conducting circuit due to the presence of a potential difference. The current at any point in a circuit is the amount of charge flowing per second; its SI unit is the ampere (coulomb per second).
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electricity - all phenomena caused by electric charge, whether static or in motion. Electric charge is caused by an excess or deficit of electrons in the charged substance, and an electric current by the movement of electrons around a circuit. Substances may be electrical conductors, such as metals, which allow the passage of electricity through them, or insulators, such as rubber, which are extremely poor conductors.
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electromagnetic waves - oscillating electric and magnetic fields traveling together through space at a speed of nearly 186,000 mi/300,000 km per second. The (limitless) range of possible wavelengths or frequencies or electromagnetic waves, which can be thought of as making up the electromagnetic spectrum, includes radio waves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
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electron microscope - instrument that produces a magnified image by using a beam of electronics instead of light rays, as in an optical microscope. An electron lens is an arrangement of electromagnetic coils that control and focus the beam. Electrons are not visible to the eye, so instead of an eyepiece there is a fluorescent screen or photographic plate on which the electrons form an image. The wavelength of the electron beam is much shorter than that of light, so much greater magnification and resolution (ability to distinguish detail) can be achieved. The development of the electron microscope has made possible the observation of very minute organisms, viruses and even large molecules.
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electronics - branch of science that deals with the emission of electronics from conductors and semiconductors, with the subsequent manipulation of these electronics, and with the construction of electronic devices. The first electronic device was the thermionic valve, or vacuum tube, in which electrons moved in a vacuum, and led to such inventions as radio, television, radar and the digital computer. Replacement of valves with the comparatively tiny and reliable transistor in 1948 revolutionized electronic development. Modern electronic devices are based on minute integrated circuits (silicon chips), wafer-thin crystal slices holding tens of thousands of electronic components).
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embodied energy - it takes energy to make something. Embodied energy is associated with the production of a good or service or the energy to prepare or make a product. Using french fries as an example, substantial energy is embodied in the planting, cultivation and harvesting of the potatoes. Then energy is used in the preparation of the French fries' packaging, transportation, marketing, storing, cooking and service to a hungry teenager. Embodied energy can be reduced by limiting food processing or by recycling.
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energy - energy can be defined as the ability to do work – the ability to exert a force. Even this definition can be confusing, though it is generally accepted. We cannot see energy – we can observe the result of energy and how it causes things to happen. One idea to assist in your understanding of energy is that objects move because energy is used to move them and that without energy, nothing would happen.
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energy conservation - methods of reducing energy use through insulation, increasing energy efficiency, and changes in patterns of use. Careless energy use by industrialized countries contributes greatly to air pollution and the greenhouse effect when it draws on nonrenewable energy sources.
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environment - Scottish historian and essayist, Thomas Carlyle, introduced the word "environment" in the 19th century to define our surroundings. In the 17th century, "environs" meant your neighborhood. Today, your "neighborhood" has reached global proportions, so much so that technology and energy consumption far removed from our community can alter the vitality of our atmosphere, ocean and land.
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externality - these are the unpaid costs and impacts of energy development and use. Externalities from smog include effects upon visibility, health and the destruction of trees. The consequences of externalities can be quite severe, from threatening our national security to possibly affecting the global climate.
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First Law of Thermodynamics - the First Law of Thermodynamics is simply a statement of the conservation of energy. Energy can be neither created nor destroyed, only transformed. No matter which form it takes, the total energy in the system is a constant.
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fission - in 1939, exiled German physicist Lise Meitner theorized that when a neutron hits a uranium nucleus, it splits the nucleus into two parts. She was soon proven correct and the reaction was called "fission" from the Latin word "fission" meaning "to split." The process releases large amounts of energy that can be used to boil water, create steam, turn a generator
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and generate electricity. formation - a formation refers to either a certain layer of the earth's crust, or a certain area of a layer. It often refers to the area of rock where a petroleum reservoir is located.
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fossil fuel - fuel, such as coal, oil and natural gas, formed from the fossilized remains of plants that lived hundreds of millions of years ago. Fossil fuels are a nonrenewable resource and will eventually run out. Extraction of coal and oil causes considerable environmental pollution, and burning coal contributes to problems of acid rain and the greenhouse effect.
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fossil fuels - stored solar energy in the form of coal, natural gas and oil. They are nonrenewable energy sources from organisms that lived long ago. Upon death, organisms under special conditions were altered chemically and physically. The word fossil is derived from the Latin word "fossilis" from "fodere" meaning "to dig." Today, we use some of that chemically-stored energy to "dig" (mine, drill, trap) for more fossil fuels. Unfortunately, our supply of fossil fuels is becoming depleted. As it is now, the burning of fossil fuels is increasing the concentration of CO2 and other pollutants, affecting the temperature and chemical reactions in our atmosphere.
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fuel - a material used to make heat or power by burning; fuel is a major operating requirement and expense of an electric utility company. Coal oil and natural gas are fossil fuels; fissionable uranium-235 is nuclear fuel.
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fuel chain - the chain of activities involved in transforming energy into forms more convenient for society. This "chain" may include some or all of the following: fuel exploration, extraction, preparation, transportation, conversion to electricity, distribution and waste disposal.
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fusion - fusion is derived from the Latin word fusus meaning to melt. It involves releasing an enormous amount of energy by joining the nuclei of small atoms. Fusion was considered by scientists as a possible energy source long before fission.
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generator - equipment made up of magnets and copper wire; the effect of the magnetic field on the copper wire creates a flow of electricity.
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geophysics - branch of earth science using physics to study the Earth's surface, interior and atmosphere. Studies also include winds, weather, tides, earthquakes, volcanoes and their effects.
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geothermal power - geothermal energy is the natural heat of the earth that is conducted or convected to the earth's surface through volcanoes and hot springs. By harnessing this energy and using it to power steam turbines,
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we can convert geothermal energy into electricity that we can use. gigawatt (GW) - one billion watts; useful for describing the capacity of large electrical energy systems.
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grid - the transmission network (or "highway") over which electricity moves from suppliers to consumers.
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grounding - by connecting an electrical circuit to the ground, current has a place to safely escape; the third wire on most electrical plugs is the ground wire.
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habitat - in ecology, the localized environment in which an organism lives. Habitats are often described by the dominant plant type or physical feature, such as a grassland habitat or rocky seashore habitat.
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heat - form of internal energy possessed by a substance by virtue of the kinetic energy in the motion of its molecules or atoms. Heat energy is transferred by conduction, convection and radiation. It always flows from a region of higher temperature (heat intensity) to one of lower temperature. Its effect on a substance may be simply to raise its temperature, or to cause it to expand, melt (if a solid), vaporize (if a liquid), or increase its pressure (if a confined gas).
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holding company - a corporation (called the parent company) that directly or indirectly owns a majority or all of the voting securities of one or more electric utility companies which are located in the same or contiguous states. The Public Utility Holding Company Act of 1935 (PUHCA) defines a holding company as a company that owns 10 percent or more of a utility. As most states do not permit a utility company which operates in another state to operate within their own boundaries, the holding company type of organization is used to bring into one family, consistent with state law, companies that can best be operated as part of an integrated utility system. Of the total number of electric utility holding companies, only a few are registered and subject to the full restrictions of PUHCA (see PUHCA in this glossary).
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host utility - the local franchised utility that serves retail consumers in its service territory.
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hydrocarbon - an organic compound containing only carbon and hydrogen. Hydrocarbons often occur in petroleum products, natural gas and coals.
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hydrocarbons - an extensive group of chemicals that always include the elements hydrogen and carbon. Natural sources of hydrocarbons are the by-products of digestion and decomposition (e.g., rotting, spoiling, putrefying). Coal, natural gas, oil, sugar, starches and plastics are all composed of hydrocarbons. The incomplete combustion of hydrocarbons from fossil fuels contributes to our pollution and global warming problems.
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hydroelectric power (HEP) - electricity generated by moving water. In a typical HEP scheme, water stored in a reservoir, often created by damming a river, is piped into water turbines, coupled to electricity generators. In pumped storage plants, water flowing through the turbines is recycled.
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hydropower - hydropower is the use of the potential energy contained in water behind dams. Release of water through dam spillways converts potential energy into kinetic energy, which is used to turn a turbine and create power that we can use.
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insulation - materials which provide a high resistance to the flow of heat, sound or electricity from one surface to another.
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insulator - any material that will not conduct electricity such as rubber.
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joule - (symbol J) - named in honor of British physicist James P. Joule (rhymes with pool) who proved in 1843 that a specific amount of work was converted into a specific amount of heat. A joule is now a unit for all forms of energy. One joule of work is done when the force of one NEWTON is exerted on an object moving in the direction of the force, a distance of one meter. It takes about one joule to lift an apple over your head. As the transition from the English system of energy measurement to the international system of units (SI) picks up momentum, we will soon become accustomed to hearing more frequently of kilojoules (Kj) and megajoules (Mj). One kilowatt-hour = 3.6 x 106 joules. One calorie = 4.187 joules.
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kilowatt - a measure of electric energy equal to 1,000 watts. Put another way, it's the amount of electric energy required to light ten 100-watt light bulbs.
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kilowatt-hour - a measure of electricity consumption equivalent to the use of 1,000 watts of power over a period of one hour. Ten 100-watt light bulbs, burning for one hour would consume one kilowatt-hour of electricity.
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kinetic energy - the energy of motion. If an object is in motion, it is capable of doing work.
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kinetic theory - theory describing the physical properties of matter in terms of the behavior -- principally movement -- of its component atoms or molecules. The temperature of a substance is dependent on the velocity of movement of its constituent particles, increased temperature being accompanied by increased movement. As gas consists of rapidly moving atoms or molecules and, according to kinetic theory, it is their continual impact on the walls of the containing vessel that accounts for the pressure of the gas. The slowing of molecular motion as temperature falls, according to kinetic theory, accounts for the physical properties of liquids and solids, culminating in the concept of no molecular motion at absolute zero (0K/-460F).
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light - electromagnetic waves in the visible range, having a wavelength from about 400 nanometers in the extreme violet to about 770 nanometers in the extreme red. Light is considered to exhibit particle and wave properties, and the fundamental particle, or quantum, of light is called the photon. The speed of light (and of all electromagnetic radiation) in a vacuum is approximately 186,000 mi/300,000 km per second, and is a universal constant denoted by c.
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load - the amount of electric power delivered or required at any specified point in a system; load also refers to the amount of electricity required by a customer or a piece of equipment. When the term refers to the sum of the demands in an electric system it is usually expressed in megawatts.
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load profiling - the study of the consumption habits of consumers to estimate the amount of power they use at various times of the day and for which they are billed. Load profiling is an alternative to precise metering.
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luminescence - emission of light from a body when its atoms are excited by means other than raising its temperature. Short-lived luminescence is called fluorescence.
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magnetism - phenomena associated with magnetic fields. Magnetic fields are produced by moving charged particles: in electromagnets, electrons flow through a coil of wire connected to a battery; in permanent magnets, spinning electrons within the atoms generate the field.
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megawatt - a unit of power equal to one million watts. Put another way, it's the amount of electric energy required to light 10,000 10-watt bulbs.
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megawatt-hour (MWH) - 1 million watts used for one hour. If you purchased a megawatt-hour of energy for a nickel per kilowatt-hour, it would cost you 1,000 nickels, or $50. Using a kWh your could burn one, 100-watt incandescent for 24 hours a day for about 14 months, or 3 hours a day for more than 9 years.
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Mercaptan - a highly concentrated odorant that is injected into natural gas before it enters a utilities distribution system. Mercaptan gives off a foul smell, reminiscent of rotten eggs.
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methane (CH4) - derived from the Greek word "methy" meaning wine. The early Greeks believed if they drank wine from cups carved from the crystal amethyst they could not become intoxicated (Greek "methyein"). Methane is a simple hydrocarbon composed of one carbon atom surrounded by four hydrogen atoms. It is an odorless, flammable and invisible gas and the primary ingredient in natural gas. Natural gas companies add a strong odorant to the gas for safety so it can be easily detected by smelling. Methane is a relatively clean fuel and it is commonly used to power vehicles in many countries, such as New Zealand and Italy.
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municipal utility - (Municipally owned electric system) - a utility that is owned and operated by a city. In most cases, municipal utility rates are set at the city level, either by the municipal administration or by a local utility board or commission. In some limited circumstances, state-level regulation applies. Municipal utilities often have access to low-cost power from federal hydroelectric projects and can obtain low interest loans, and they are exempt from income and other taxes at the federal and state levels. These factors contribute to lower financing costs for plant and equipment. Municipal utilities serve roughly 14 percent of U.S. electric consumers.
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natural gas - mixture of flammable gases found in the Earth's crust (often in association with petroleum), now one of the world's three main fossil fuels (with coal and oil). Natural gas is a mixture of hydrocarbons, chiefly methane, with ethane, butane and propane.
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neutron - one of the three chief subatomic particles (the others being the proton and the electron). Neutrons have about the same mass as protons but no electric charge, and occur in the nuclei of all atoms except hydrogen. They contribute to the mass of atoms but do not affect their chemistry, which depends on the proton or electron numbers. For instance, isotopes of a single element (with different masses) differ only in the number of neutrons in their nuclei and have identical chemical properties.
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North American Electric Reliability Council (NERC) - a nonprofit organization formed by the electric utility industry to ensure reliable, adequate power supply in North America. NERC plays an important role in establishing the standards, rules and forms of cooperation that make a major contribution to system reliability. NERC was formed in 1969 and is organized through 10 regional councils comprised of individual electric utilities in the U.S., Canada and Mexico. The transmission systems of the members of these regional councils are interconnected, creating flexible regional systems that allow the transfer of power among areas to maintain one of the world's most reliable electric systems.
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nuclear energy - energy from the inner core or nucleus of the atom, as opposed to energy released in chemical processes, which is derived from the electrons surrounding the nuclei. Nuclear fusion is the release of thermonuclear energy by the conversion of hydrogen nuclei to helium nuclei, in a continuing reaction in the sun and other stars. Nuclear fusion is the principle behind thermonuclear weapons (the hydrogen bomb). Attempts to harness fusion for commercial power production have so far not succeeded.
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nuclear fission - process whereby an atomic nucleus breaks up into two or more major fragments with the emission of two or three neutrons. It is accompanied by the release of energy in the form of gamma radiation and the kinetic energy of the emitted particles.
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nuclear fusion - process where two atomic nuclei are fused, with the release of a large amount of energy. Very high temperatures and pressures are thought to be required in order for the process to happen. Under these conditions the atoms involved are stripped of all their electrons so that the remaining particles, which together make up plasma, can come close together at very high speeds and overcome the mutual repulsion of the positive charges on the atomic nuclei. At very close range another nuclear force will come into play, fusing the particles together to form a larger nucleus. As fusion is accompanied by the release of large amounts of energy, the process might one day be harnessed to form the basis of commercial energy production. Methods of achieving controlled fusion are therefore the subject of research around the world.
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nuclear waste - the radioactive and toxic byproducts of the nuclear-energy and nuclear-weapons industries. Nuclear waste may have an active life of several thousand years. Disposal, by burial on land or at sea, has raised problems of safety, environmental pollution and security. In absolute terms, nuclear waste cannot be safely relocated or disposed of.
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nucleus - in physics, the positively charged central part of an atom, which constitutes almost all its mass. Except for hydrogen nuclei, which have only protons, nuclei are composed of both protons and neutrons. Surrounding the nucleus are electrons, which contain a negative charge equal to the protons, thus giving the atom a neutral charge.
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obligation to serve - the responsibility of a regulated utility, under traditional regulation, to provide service to all consumers in its service territory on a nondiscriminatory basis. This means that utilities must build, operate and maintain generating plants and transmission and distribution systems to serve all their present and future consumers.
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OHM - a measure of electrical resistance; one volt will force a current of one ampere through a resistance of one ohm.
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oil - a mixture of hydrocarbons existing in a liquid state in natural underground reservoirs; a fossil fuel.
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outlet - place to plug in appliances and other devices that operate on electricity.
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ozone (O3) - highly reactive pale-blue gas with a penetrating odor. Ozone is an allotrope of oxygen made up of three atoms of oxygen. It is formed when the molecule of the stable form of oxygen (O2) is split by ultraviolet radiation or electrical discharge. It forms a thin layer in the upper atmosphere, which protects life on Earth from ultraviolet rays, a cause of skin cancer. At lower atmosphere levels it is an air pollutant and contributes to the greenhouse effect.
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particulates - from the Latin word "partire" meaning to divide, distribute or "part of." Particulates can be suspended solids or liquids that include dust from automobile and truck brake linings, road grit, ash from factory smokestacks, some from home chimneys and aerosols. Particulates reduce visibility and can cause lung and eye damage, especially when combined with other pollutants such as sulfur oxides (SOx) and nitrous oxides (NOx). Many people with respiratory problems are unaware their breathing problems can result from particulate pollution.
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photovoltaic cells - photovoltaic cells are used to directly convert solar radiation into electricity. Materials called semiconductors, usually made from pure silicon, transfer light energy (photons) into electrical energy in a process known as the photoelectric effect.
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potential energy - the stored energy a body possesses because of its position with respect to other bodies. A stretched rubber band has potential energy. Gasoline in the liquid state has potential energy. When it is burned, it releases its chemical kinetic energy.
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potential, electric - in physics, the relative electrical state of an object. A charge conductor, for example, has a higher potential than the Earth, whose potential is taken by convention to be zero. An electric cell (battery) has a potential in relation to emf (electromotive force), which can make current flow in an external circuit. The difference in potential between two points – the potential difference – is expressed in volts; that is, a 12V battery has a potential difference of 12 volts between its negative and positive terminals.
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power - the rate at which work is done or how much work is accomplished, divided by how long it took to do the work. The unit of power is the watt (W) or joule per second. If you lift a bean burrito above your head in one second, you have used about one watt of power. The word power is derived from the Latin word "posse" meaning "be able.
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power grid - a network of electric power lines and associated equipment used to transmit and distribute electricity over a geographic area.
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Public Utilities Commission - the state regulatory agency that governs retail utility rates and practices and, in many cases, issues approvals for the construction of new generation and transmission facilities. On average, roughly 90 percent of a utility's operations are regulated by the state commission.
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quad - a quadrillion BTUs (1015 BTUs). This is an enormous number equivalent to 3.6 x 106 metric tons of coal, or 172,000,000 (1.72 x 106) barrels of oil. A quadrillion is the number one followed by 15 zeros. It would be impossible to count to such a number even if you counted by 1,000s for every second of your life until you were 100 years old.
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raw material - the original material as taken from its source, usually the ground. A good example is bauxite ore that is used to make aluminum.
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recycle - to recycle is to put into the cycle again. In other words, to take a product and reuse it when discarded. Recycling saves enormous amounts of energy and raw materials.
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reliability - the ability to deliver uninterrupted electricity to consumers on demand, and to withstand sudden disturbances such as short circuits or loss of major system components. This encompasses both the reliability of the generation system and of the transmission and distribution system. Reliability may be evaluated by the frequency, duration and magnitude of any adverse effects on consumer service.
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resistance - in physics, that property of a substance that restricts the flow or electricity through it, associated with the conversion of electrical energy to heat; also the magnitude of this property. Resistance depends on many factors, such as the nature of the material, its temperature, dimensions, and thermal properties; degree of impurity; the nature and state of illumination of the surface; and the frequency and magnitude of the current. The SI unit of resistance is the ohm.
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resource - from the Latin word "resurgere" meaning "to rise again." A substance for which there is an identifiable use within society. Prior to 1939, uranium was not a resource until it was developed for use in nuclear power, medicine and weapons production.
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retail consumers - consumers, including residences and businesses, who themselves use the electricity that they purchase; also referred to as end-use consumers.
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retail wheeling - a transmission or distribution service by which utilities deliver electric power sold by a third party directly to retail consumers. This would allow an individual retail consumer to choose his or her electricity supplier, but still receive delivery using the power lines of the local utility.
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rural electric cooperative - (Cooperatively owned electric utility) - a consumer-owned electric utility that was created to transmit and distribute power in rural areas. Rural electric cooperatives benefit from below-market financing from the Rural Utilities Service (formerly the Rural Electrification Administration), as well as low-cost power from federal hydroelectric projects. In addition, most do not pay state or federal income taxes. Rates for rural electric cooperatives typically are set by a board of directors elected from among the cooperative's members.
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second law of thermodynamics - the Second Law of Thermodynamics states that the universe constantly tends toward a state of maximum disorder, or entropy. No process involving energy transformation will spontaneously occur unless energy is degraded from an orderly, concentrated form into a disorderly, dispersed form.
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service obligation - a term used to mean the duties a regulated public utility must perform for its consumers. Service obligation includes the duty to serve all prospective consumers; provide adequate, reliable service; and render safe, efficient and nondiscriminatory service.
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shareholder-owned electric utilities - public utilities that are owned by shareholders, organized as corporations, and regulated by FERC and state public utilities commissions. About three-quarters of all Americans receive electric service from shareholder-owned electric utilities. The majority of electric utility shareholders are at or near retirement age and are looking for income to supplement pensions and Social Security benefits.
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solar energy - energy derived from the sun's radiation. The amount of energy falling on just 0.3861 sq. mil/1 sq. km is about 4,000 megawatts, enough to heat and light a small town. In one second the sun gives off 13 million times more energy than all the electricity used in the U.S. in one year. Solar energy may also be harnessed indirectly using solar cells (photovoltaic cells) made of panels of semiconductor material (usually silicon), which generate electricity when illuminated by sunlight. Although it is difficult to generate a high output from solar energy compared to sources such as nuclear or fossil fuels, it is a clean, renewable energy.
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stranded cost - costs that were incurred by utilities to serve their consumers with the understanding that state regulatory commissions would allow the costs to be recovered through electric rates. Stranded costs can occur either because particular consumers discontinue their use of a service or because such consumers are no longer willing to pay the full costs incurred to provide a service. Potentially stranded costs are the result of decisions that were reviewed and approved by government regulators and were made by utilities under the unique regulatory compact with their state and their consumers. The Federal Energy Regulatory Commission (FERC) has determined that stranded costs at the wholesale level should be paid by electric consumers desiring to exit a system built to serve them.
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substation - a set of transformers that change the voltage of electrical energy to levels appropriate for end use.
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sulfur dioxide (SO2) - a corrosive gas produced both by nature and technology in nearly equal amounts. Burning fuels, such as coal and oil, that contain sulfur produces SO2. It is also produced from sea spray, organic decomposition and volcanic eruptions. When combined with water in the air, it produces a weak, corrosive sulfuric acid – an ingredient of "acid rain." The control of SO2 has been given the highest priority at utility companies.
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tariff - a collection of public schedules detailing utility cost-of-service rates, rules, service territory, and terms of service that a regulated utility files with its public utilities commission for official approval. Tariffs that have been approved by a Public Utilities Commission are binding legal documents and must be made available to the public. In effect, they constitute the contract between a utility and its consumers.
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telecommunications - communications over a distance, generally by electronic means. Today it is possible to communicate with most countries by telephone cable, or by satellite or microwave link, with over 100,000 simultaneous conversations and several television channels being carried by the latest satellites. Integrated-Services Digital Network (ISDN) makes videophone and high-quality fax possible; the world's first large-scale center of ISDN began operating in Japan 1988. ISDN is a system that transmits voice and image data on a single transmission line by changing them into digital signals. The chief method of relaying long-distance calls on land is microwave radio transmission.
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temperature - state of hotness or coldness of a body, and the condition that determines whether or not it will transfer heat to, or receive heat from, another body according to the laws of thermodynamics. It is measured in degrees Celsius (before 1948 called centigrade), Kelvin or Fahrenheit. The normal temperature of the human body is about 98.6F/37C. Variation by more than a degree or so indicates ill health, a rise signifying excessive activity (usually due to infection), and a decrease signifying deficient heat production (usually due to lessened vitality).
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therm - a unit of energy equivalent to 100,000 BTUs. Usually used as a measure of the heat energy from burning natural gas (or methane).
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thermodynamics - branch of physics dealing with the transformation of heat into and from other forms of energy. It is the basis of the study of the efficient working of engines, such as the steam and internal-combustion engines. The three laws of thermodynamics are 1) energy can be neither created nor destroyed, heat and mechanical work being mutually convertible; 2) it is impossible for an unaided self-acting machine to convey heat from one body to another at a higher temperature; and 3) it is impossible by any procedure, no matter who idealized, to reduce any system to the absolute zero of temperature (K/-460F) in a finite number of operations. Put into mathematical form, these laws have widespread applications in physics and chemistry.
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transformer - an electromagnetic device for increasing or decreasing electrical voltage.
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transformer lines - wires or cables through which high-voltage electric power is moved from point to point.
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turbine - engine in which steam, water, gas or air (see windmill) is made to spin a rotating shaft by pushing on angled blades, like a fan. Turbines are among the most powerful machines. Steam turbines are used to drive generators in power stations and ships' propellers; water turbines spin the generators in hydroelectric power.
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volt - a unit of electrical pressure; the force at which electrical charges move through conductors. In the U.S. 120V is standard; 220-240V are standard in foreign countries.
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watt - a unit of power defined as a joule of energy per second. Named in honor of James Watt who in 1765 constructed the first practical steam engine, originally used to power mechanical pumps to remove water from coal mines (see joules).
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wholesale consumer - any entity that purchases electricity at the wholesale level, including municipal utilities, private utilities, rural electric cooperatives, or government-owned utility districts. Wholesale consumers purchase electricity from other wholesale suppliers to resell to their own retail consumers.
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wholesale wheeling - the process of sending electricity from one utility to another wholesale purchaser over the transmission lines of an intermediate utility. Under the Energy Policy Act of 1992, utilities are required to provide wholesale transmission wheeling services to any electric utility, federal power marketing agency, or other company generating electric energy for sale in the wholesale market.
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wind turbine - windmill of advanced aerodynamic design connected to an electricity generator and used in windpower installations. Wind turbines can be either large propeller-type rotors mounted on a tall tower, or flexible metal strips fixed to a vertical axle at top and bottom.
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work - the physical or mechanical use of energy for accomplishing a specific task. Work is equal to force times distance, or power (energy) over time. Work as accomplished by energy is described by BTUs, watt-hours or kilowatt-hours.
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