Eia/Standard Frequency Assignments For Kids

North American television frequencies are different for over-the-air (also called terrestrial) and cable television systems. Over-the-air television channels are divided into two bands: the VHF band which comprises channels 2 through 13 and occupies frequencies between 54 and 216 MHz, and the UHF band, which comprises channels 14 through 83 and occupies frequencies between 470 and 890 MHz. These bands are different enough in frequency that they often require separate antennas to receive (although many antennas cover both VHF and UHF), and separate tuning controls on the television set. The VHF band is further divided into two frequency ranges: VHF low band (Band I) between 54 and 88 MHz, containing channels 2 through 6, and VHF high band (Band III) between 174 and 216 MHz, containing channels 7 through 13. The wide spacing between these frequency bands is responsible for the complicated design of rooftop TV antennas. The UHF band has higher noise and greater attenuation, so higher gain antennas are often required for UHF.

Broadcast television[edit]


Further information: § Historical band plans

The VHF band plan was modified several times before 1948. The last of these changes was the deletion of channel 1, originally intended as a community channel. This allocation of the spectrum was given to two-way land-mobile radio.[1]

UHF channels 70-83 in the United States were reallocated in 1983. As of 2016,[clarification needed] channels 52-69 are not available for normal, high-power digital television broadcasting in the United States, but some channels are available for use as low-power or translator stations.[2]

In March 2008, the FCC requested public comment on turning the bandwidth currently occupied by analog television channels 5 and 6 (76–88 MHz) over to extending the FM broadcast band when the digital television transition was to be completed in February 2009 (ultimately delayed to June 2009).[3] This proposed allocation would effectively assign frequencies corresponding to the existing Japanese FM radio service (which begins at 76 MHz) for use as an extension to the existing North American FM broadcast band.[4][needs update]

700 MHz band[edit]

Wireless microphones and medicaltelemetry devices formerly shared some of the TV bands, but transmitted at a very low power. After the migration of digital television in 2009, the Federal Communications Commission (FCC) banned these from using the 700 MHz band in the U.S., effective June 12, 2010. The 700 MHz band is now used for public safety communications and wireless broadband providers.[5]

600 MHz band[edit]

In 2015 the FCC has announced the possible auction of all remaining spectrum including and above channel 38.[6] Such decision would require the reconfiguration of channel allotment (known in the broadcast TV industry as the channel "repack"), and would allow for higher gain small antennas. This could preclude the auction of some or all remaining VHF or UHF spectrum, a decision that would then allow further yet smaller high gain antennas. In April 2017, it has since been decided that channels 38 and above will be deleted, but channel 37 remains reserved.

Channel frequencies[edit]

VHF band[edit]

 Channel  Lower edge  Video carrier  ATSC pilot  Audio carrier  Upper edge 
(Gap in band plan)
 Channel  Lower edge   Video carrier  ATSC pilot  Audio carrier  Upper edge 

UHF band[edit]

The following table lists over-the-air television channels in the ultra high frequency band. Some entries have a colored background, indicating that the channels have been reallocated for other use. The notes below the table explain the re-allocations.

 Channel  Lower edge  Video carrier  ATSC pilot  Audio carrier  Upper edge 


  • Channel 37 is reserved for radio astronomy in the United States, Canada, Bermuda and the Bahamas, thus there are no television stations assigned to it. Mexico also informally observes a ban on transmitters using this channel.
  • On August 22, 2011, the United States' Federal Communications Commission announced a freeze on all future applications for broadcast stations requesting to use channel 51,[7] to prevent adjacent-channel interference to the A-Block of the 700 MHz band. Later that year (on December 16, 2011), Industry Canada and the CRTC followed suit in placing a moratorium on future television stations using Channel 51 for broadcast use for the same reason.[8]
  • Channels 52 through 69 in the United States have been reallocated now that conversion to digital TV was completed on June 12, 2009, although some low-power and translator stations may still be in use on these channels.[2]
  • The frequencies used by UHF channels 70 through 83 were reallocated to the Land Mobile Radio System (Public Safety and Trunked Radio) and mobile phones in a CCIR worldwide convention in 1983.[2][additional citation(s) needed]
  • With the advent of digital television in 2009, stations are allowed to identify themselves by a virtual channel that may not necessarily be the same as the station's RF channel. Virtual channels 1, 37, and 70 to 99 can be assigned via PSIP even though there is no corresponding physical station on that RF channel.[9]
Cable television frequency issues
  • UHF channels 14 to 43 translate to common cable-ready channels 65 to 94 (add 51).
  • UHF channels 44 to 69 translate to rarely used cable TV channels 100 to 125 (add 56).
  • Cable-ready channels 6, 95, 96, and 97 have audio carriers which overlap FM radio stations (87.7 ,95.7, 101.7 and 107.7).

Historical band plans[edit]

 Channel  Lower edge  Video carrier  Audio carrier  Upper edge  Current U.S. use 
15051.2555.7556Amateur band, TV ch. 2 (deprecated)
(Break in band plan)
26667.2571.7572TV ch. 4 (deprecated)
37273.2577.7578Radio-controlled car/plane hobby, TV ch. 5
47879.2583.7584TV ch. 5
58485.2589.7590TV ch. 6, FM radio
(Break in band plan)
69697.25101.75102FM radio
7102103.25107.75108FM radio
 Channel  Lower edge  Video carrier  Audio carrier  Upper edge  Current U.S. use 
8162163.25167.75168NOAA Weather Radio (162)
(Break in band plan)
9180181.25185.75186TV ch. 8
10186187.25191.75192TV ch. 9
(Break in band plan)
11204205.25209.75210TV ch. 12
12210211.25215.75216TV ch. 13
(Break in band plan)
(Break in band plan)
(Break in band plan)

Cable television[edit]

Harmonically-related carriers (HRC)[edit]

Harmonically-related carriers (HRC) is a system for assigning television channel numbers to bands of frequencies over a cable TV network.[citation needed] William Grant, in his book,[10] states:

"By harmonically relating the carrier frequencies themselves it is … possible to improve system performance. This does not reduce the beats produced, but positions them within the system transmission spectrum, such that they are more tolerable. In effect, all signal carriers are spaced precisely at 6 MHz apart, and thus, all beats generated are at 6 MHz increments." "Since the television signals are vestigial sideband modulation, if the beat products can be manipulated to fall on or near the RF carriers themselves, they are much less offensive."

Incrementally-related carriers (IRC)[edit]

Incrementally-related carriers (IRC) is a system for assigning television channel numbers to bands of frequencies over a cable TV network.[11] The IRC plan attempts to minimize distortion products by deriving all video carrier signals from a common source.[12] The IRC system assigns channel frequencies (for the North American NTSC-M system) spaced 6 MHz apart. In an IRC system, the VHF channels are at their off-air frequencies except for channels 5 and 6, which will be 2 MHz higher than usual.[13]

Channel frequencies[edit]

These frequencies are used for both NTSC-based analog television and QAM-based digital television. Band plans for North American cable television systems are standardized in EIA standard 542-B.[14]

Channels 57 to 61, and 143 to 145, are used in amateur television.

NOTE: Frequencies given are for luminance carriers. For channel center frequencies, add 1.75 MHz.
Channel numberChannel letterStandard video carrier (MHz)Harmonically-related video carrier (MHz)Incrementally-related video carrier (MHz)QAM / CDSREF carrier (MHz)Audio carrier (MHz)
Subband "T" channels
(Break in band plan)
55 (or A-7)77.2578.003979.2579.00 or 81.0081.75 or 83.75
66 (or A-6)83.2584.004285.2585.00 or 87.0087.75 or 89.75
37AA or W+1301.25300.0150301.25303.00305.75
38BB or W+2307.25306.0153307.25309.00311.75
39CC or W+3313.25312.0156313.25315.00317.75
40DD or W+4319.25318.0159319.25321.00323.75
41EE or W+5325.25324.0162325.25327.00329.75
42FF or W+6331.25330.0165331.25333.00335.75
43GG or W+7337.25336.0168337.25339.00341.75
44HH or W+8343.25342.0171343.25345.00347.75
45II or W+9349.25348.0174349.25351.00353.75
46JJ or W+10355.25354.0177355.25357.00359.75
47KK or W+11361.25360.0180361.25363.00365.75
48LL or W+12367.25366.0183367.25369.00371.75
49MM or W+13373.25372.0186373.25375.00377.75
50NN or W+14379.25378.0189379.25381.00383.75
51OO or W+15385.25384.0192385.25387.00389.75
52PP or W+16391.25390.0195391.25393.00395.75
53QQ or W+17397.25396.0198397.25399.00401.75
54RR or W+18403.25402.0201403.25405.00407.75
55SS or W+19409.25408.0204409.25411.00413.75
56TT or W+20415.25414.0207415.25417.00419.75
57UU or W+21421.25420.0210421.25423.00425.75
58VV or W+22427.25426.0213427.25429.00431.75
59WW or W+23433.25432.0216433.25435.00437.75
60XX or W+24439.25438.0219439.25441.00443.75
61YY or W+25445.25444.0222445.25447.00449.75
62ZZ or W+26451.25450.0225451.25453.00455.75
63AAA or W+27457.25456.0228457.25459.00461.75
64BBB or W+28463.25462.0231463.25465.00467.75
65CCC or W+29469.25468.0234469.25471.00473.75
66DDD or W+30475.25474.0237475.25477.00479.75
67EEE or W+31481.25480.0240481.25483.00485.75
68FFF or W+32487.25486.0243487.25489.00491.75
69GGG or W+33493.25492.0246493.25495.00497.75
70HHH or W+34499.25498.0249499.25501.00503.75
71III or W+35505.25504.0252505.25507.00509.75
72JJJ or W+36511.25510.0255511.25513.00515.75
73KKK or W+37517.25516.0258517.25519.00521.75
74LLL or W+38523.25522.0261523.25525.00527.75
75MMM or W+39529.25528.0264529.25531.00533.75
76NNN or W+40535.25534.0267535.25537.00539.75
77OOO or W+41541.25540.0270541.25543.00545.75
78PPP or W+42547.25546.0273547.25549.00551.75
79QQQ or W+43553.25552.0276553.25555.00557.75
80RRR or W+44559.25558.0279559.25561.00563.75
81SSS or W+45565.25564.0282565.25567.00569.75
82TTT or W+46571.25570.0285571.25573.00575.75
83UUU or W+47577.25576.0288577.25579.00581.75
84VVV or W+48583.25582.0291583.25585.00587.75
85WWW or W+49589.25588.0294589.25591.00593.75
86XXX or W+50595.25594.0297595.25597.00599.75
87YYY or W+51601.25600.0300601.25603.00605.75
88ZZZ or W+52607.25606.0303607.25609.00611.75
8989 or W+53613.25612.0306613.25615.00617.75
9090 or W+54619.25618.0309619.25621.00623.75
9191 or W+55625.25624.0312625.25627.00629.75
9292 or W+56631.25630.0315631.25633.00635.75
9393 or W+57637.25636.0318637.25639.00641.75
9494 or W+58643.25642.0321643.25645.00647.75
100100 or W+59649.25648.0324649.25651.00653.75
101101 or W+60655.25654.0327655.25657.00659.75
102102 or W+61661.25660.0330661.25663.00665.75
103103 or W+62667.25666.0333667.25669.00671.75
104104 or W+63673.25672.0336673.25675.00677.75
105105 or W+64679.25678.0339679.25681.00683.75
106106 or W+65685.25684.0342685.25687.00689.75
107107 or W+66691.25690.0345691.25693.00695.75
108108 or W+67697.25696.0348697.25699.00701.75
109109 or W+68703.25702.0351703.25705.00707.75
110110 or W+69709.25708.0354709.25711.00713.75
111111 or W+70715.25714.0357715.25717.00719.75
112112 or W+71721.25720.0360721.25723.00725.75
113113 or W+72727.25726.0363727.25729.00731.75
114114 or W+73733.25732.0366733.25735.00737.75
115115 or W+74739.25738.0369739.25741.00743.75
116116 or W+75745.25744.0372745.25747.00749.75
117117 or W+76751.25750.0375751.25753.00755.75
118118 or W+77757.25756.0378757.25759.00761.75
119119 or W+78763.25762.0381763.25765.00767.75
120120 or W+79769.25768.0384769.25771.00773.75
121121 or W+80775.25774.0387775.25777.00779.75
122122 or W+81781.25780.0390781.25783.00785.75
123123 or W+82787.25786.0393787.25789.00791.75
124124 or W+83793.25792.0396793.25795.00797.75
125125 or W+84799.25798.0399799.25801.00803.75
126126 or W+85805.25804.0402805.25807.00809.75
127127 or W+86811.25810.0405811.25813.00815.75
128128 or W+87817.25816.0408817.25819.00821.75
129129 or W+88823.25822.0411823.25825.00827.75
130130 or W+89829.25828.0414829.25831.00833.75
131131 or W+90835.25834.0417835.25837.00839.75
132132 or W+91841.25840.0420841.25843.00845.75
133133 or W+92847.25846.0423847.25849.00851.75
134134 or W+93853.25852.0426853.25855.00857.75
135135 or W+94859.25858.0429859.25861.00863.75
136136 or W+95865.25864.0432865.25867.00869.75
137137 or W+96871.25870.0435871.25873.00875.75
138138 or W+97877.25876.0438877.25879.00881.75
139139 or W+98883.25882.0441883.25885.00887.75
140140 or W+99889.25888.0444889.25891.00893.75
141141 or W+100895.25894.0447895.25897.00899.75
142142 or W+101901.25900.0450901.25903.00905.75
143143 or W+102907.25906.0453907.25909.00911.75
144144 or W+103913.25912.0456913.25915.00917.75
145145 or W+104919.25918.0459919.25921.00923.75
146146 or W+105925.25924.0462925.25927.00929.75
147147 or W+106931.25930.0465931.25933.00935.75
148148 or W+107937.25936.0468937.25939.00941.75
149149 or W+108943.25942.0471943.25945.00947.75
150150 or W+109949.25948.0474949.25951.00953.75
151151 or W+110955.25954.0477955.25957.00959.75
152152 or W+111961.25960.0480961.25963.00965.75
153153 or W+112967.25966.0483967.25969.00971.75
154154 or W+113973.25972.0486973.25975.00977.75
155155 or W+114979.25978.0489979.25981.00983.75
156156 or W+115985.25984.0492985.25987.00989.75
157157 or W+116991.25990.0495991.25993.00995.75
158158 or W+117997.25996.0498997.25999.001001.75

Channel usage[edit]

Cable channels 98 and 99 (A2 and A1, 108-120 MHz), if used, have appeared as channel 00 and 01 respectively on some cable boxes.[15]

See also[edit]


  1. ^http://www.tech-notes.tv/History&Trivia/Channel%20One/Channel_1.htm
  2. ^ abc"FCC Online Table of Frequency Allocations 47 C.F.R. § 2.106"(PDF). Federal Communications Commission. 2016-08-31. Archived from the original(PDF) on 2016-10-30. 
  3. ^Federal Communications Commission (2008-05-16). "In the Matter of Promoting Diversification of Ownership in the Broadcasting Services". Retrieved 2013-07-03.   73 FR28400, 73 FR28403
  4. ^Could EXB Band Be Your New Home?RadioWorld September 10, 2008
  5. ^"Distribution, Sale and Use of Wireless Microphones Operating in the 700 MHz Band Prohibited". FCC. 
  6. ^http://www.tvtechnology.com/news/0002/fcc-releases-incentive-auction-clearing-target/278576
  7. ^ abFCC Public Notice DA-11-1428A1:
  8. ^ abIndustry Canada Advisory Letter - Moratorium on the Use of Television Channel 51
  9. ^"What is the difference between a RF channel and a virtual channel?". ChannelMaster. Retrieved 2014-12-22. 
  10. ^Cable Television, 2nd edition, GWG Associates, Schoharie, NY, 1988, page 82
  11. ^http://www.jneuhaus.com/fccindex/cablech.html#irc
  12. ^Walter S. Ciciora (ed), Modern cable television technology: video, voice, and data communications , Morgan Kaufmann, 2004 ISBN 1-55860-828-1, page 399
  13. ^http://www.hackerscatalog.com/Services/TECH_Notes/eleven.html
  14. ^Walter S. Ciciora, Modern cable television technology: video, voice, and data communications Morgan Kaufmann, 2004 ISBN 1-55860-828-1, pages 397-402
  15. ^"Technical Notes". HackersCatalog.com. Extreme Media. 2012. Archived from the original on 2014-07-14. Retrieved 2016-08-12. 

External links[edit]

File Scrub 1 ::::: EK ... kids_glossary

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Activation Energy - Activation energy of a reaction is the amount of energy needed to start the reaction.

Active Heating System - A solar water or space-heating system that moves heated air or water using pumps or fans.

Air-Conditioning - Cooling and dehumidifying the air in a building by a refrigeration unit by a refrigeration unit powered by electricity or natural gas. This definition excludes fans, blowers, or evaporative cooling systems (swamp coolers) that are not connected to a refrigeration unit. (See this word used in context.)

Air-Conditioning Equipment - Either a central system, window or wall units that cool the air in a housing unit by a refrigeration unit powered by electricity or natural gas. This definition excludes fans, blowers, or evaporative cooling systems (swamp coolers) that are not connected to a refrigeration unit.

Alternating Current - An electric current that reverses its direction at regular intervals or cycles; In the U.S. the standard is 120 reversals or 60 cycles per second; typically abbreviated as AC. (See this word used in context.)

Alternative Fuel - A popular term for "non-conventional" transportation fuels made from natural gas (propane, compressed natural gas, methanol, etc.) or biomass materials (ethanol, methanol).

Alternative-Fuel Vehicle (AFV) - A vehicle designed to operate on an alternative fuel (e.g., compressed natural gas, methane blend, electricity). The vehicle could be either a vehicle designed to operate exclusively on alternative fuel or a vehicle designed to operate on alternative fuel and/or a traditional fuel.

Ampere - A unit of measure for an electrical current; the amount of current that flows in a circuit at an electromotive force of one Volt and at a resistance of one Ohm. Abbreviated as amp.

Anthropogenic - Made or generated by a human or caused by human activity. The term is used in the context of global climate change to refer to gaseous emissions that are the result of human activities, as well as other potentially climate-altering activities, such as deforestation.

Appliance - A piece of equipment, commonly powered by electricity, used to perform a particular energy-driven function. Examples of common appliances are refrigerators, clothes washers and dishwashers, conventional ranges/ovens and microwave ovens, humidifiers and dehumidifiers, toasters, radios, and televisions. (See this word used in context.)

Atomic Structure - The conceptualized concept of an atom, regarded as consisting of a central positively charged nucleus (protons and neutrons) and a number of negatively charged electrons revolving about in various orbits.

Average - The simple arithmetic average for a population; that is, the sum of all the values in a population divided by the size of the population. Population means are estimated by computing the weighted sum of the sample values, then dividing by the sum of the sample weights.

Avoided Cost - A renewable or cogeneration facility that qualifies for PURPA benefits is called a Qualifying Facility (QF). Utility companies buy the electricity from QFs at the "avoided cost." This is the cost it would take for the utility company to generate the amount of electricity the QF produces.

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Barrel: A unit of volume equal to 42 U.S. gallons. One barrel weights 306 pounds or 5.80 million Btu of crude oil. Barrel is abbreviated as bbl.
Also, see a brief list of Barrels, and convert barrels into other units using the energy calculator.

Battery - An energy storage device made up of one or more electrolyte cells.

Biodiesel - An alternative fuel that can be made from any fat or vegetable oil. It can be used in any diesel engine with few or no modifications. Although biodiesel does not contain petroleum, it can be blended with diesel at any level or used in its pure form.

Biogenic waste - Waste made from materials that were produced by living organisms or biological processes. Note: EIA uses the term "biogenic" to refer only to organic nonfossil material of biological origin, such as paper or cotton.

Biofuels - Liquid fuels and blending components produced from biomass (plant) feedstocks, used primarily for transportation.

Bioreactor - A landfill where the waste actively decomposes rather being simply buried in a "dry tomb."

Biomass - Any organic (plant or animal) material which is available on a renewable basis, including agricultural crops and agricultural wastes and residues, wood and wood wastes and residues, animal wastes, municipal wastes, and aquatic plants.
See our brief sections on: Biomass Energy and Biomass Energy Milestones.

Boiler - A tank in which water is heated to produce either hot water or steam that is circulated for the purpose of heating and power.

Boiling Water Reactor - A nuclear reactor in which water is allowed to boil in the core. The resulting steam is used to drive a turbine generating electric power.

British thermal unit (Btu) - The amount of heat required to raise the temperature of one pound of water one degree Fahrenheit; equal to 252 calories. British thermal unit is abbreviated as Btu. See our section on using Btu to compare energy.

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Calorie - A unit for measuring heat energy. This unit is equal to 4.184 joules. Often used instead of joules when dealing with the energy released from food.

Carbon Dioxide - A colorless, odorless noncombustible gas with the formula CO2 that is present in the atmosphere. It is formed by the combustion of carbon and carbon compounds (such as fossil fuels and biomass) and by respiration, which is a slow combustion in animals and plants, and by the gradual oxidation of organic matter in the soil.

Chain Reaction - A self-sustaining nuclear reaction which takes place during fission. A fissionable substance (i.e., uranium) absorbs a neutron and divides, releasing additional neutrons that are absorbed by other fissionable nuclei, releasing still more neutrons.

Chemical Energy - Energy stored in a substance and released during a chemical reaction such as burning wood, coal, or oil.

Circuit(s) - A conductor or a system of conductors through which electric current flows.

Climate Change - A term used to refer to all forms of climatic inconsistency, but especially to significant change from one prevailing climatic condition to another. In some cases, "climate change" has been used synonymously with the term "global warming"; scientists, however, tend to use the term in a wider sense inclusive of natural changes in climate, including climatic cooling.

Coal - A fossil fuel formed by the breakdown of vegetable material trapped underground without access to air.
See our brief sections on: Coal and Coal Milestones.

Coal-Fired Power Plant - A power plant that uses coal as the fuel to generate electricity.

Cofiring - The process of burning natural gas in conjunction with another fuel to reduce air pollutants.

Cogeneration - The production of electrical energy and another form of useful energy (such as heat of steam) through the sequential use of energy.

Collector Field - The area where many solar collectors are situated in a solar power plant.

Combustion - Chemical oxidation accompanied by the generation of light and heat.

Commercial Sector (of Economy) - The part of the economy having to do with the buying and selling of goods and services. The commercial sector is made up of merchants, businesses, etc.

Conversion Factors - A number that translates units of one measurement system into corresponding values of another measurement system. See our Energy Calculator.

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Deforestation - The net removal of trees from forested land.

Derrick - A frame tower that supports the drill equipment used to find oil and natural gas in the earth.

Diesel Engine -Diesel engines are internal combustion engines that burn diesel oil rather than gasoline.

Diesel Fuel - A fuel composed of distillates obtained in petroleum refining operation or blends of such distillates with residual oil used in motor vehicles. The boiling point and specific gravity are higher for diesel fuels than for gasoline.

Direct Current - An electric current that flows in only one direction through a circuit, as from a battery.

Distillate Fuel Oil - A general classification for one of the petroleum fractions produced in conventional distillation operations. It includes diesel fuels and fuel oils. Products known as No. 1, No. 2, and No. 4 diesel fuel are used in on-highway diesel engines, such as those in trucks and automobiles, as well as off-highway engines, such as those in railroad locomotives and agricultural machinery. Products known as No. 1, No. 2, and No. 4 fuel oils are used primarily for space heating and electric power generation.

Distillation Unit (atmospheric) - The primary distillation unit that processes crude oil (including mixtures of other hydrocarbons) at approximately atmospheric conditions. It includes a pipe still for vaporizing the crude oil and a fractionation tower for separating the vaporized hydrocarbon components in the crude oil into fractions with different boiling ranges. This is done by continuously vaporizing and condensing the components to separate higher oiling point material.

DOE - U.S. Department of Energy.

Drilling - The act of boring a hole (1) to determine whether minerals are present in commercially recoverable quantities and (2) to accomplish production of the minerals (including drilling to inject fluids). There are three types of drilling : exploratory - drilling to locate probable mineral deposits or to establish the nature of geological structures; such wells may not be capable of production if minerals are discovered; developmental - drilling to delineate the boundaries of a known mineral deposit to enhance the productive capacity of the producing mineral property; and directional - drilling that is deliberately made to depart significantly from the vertical.

Dynamo - A device that changes mechanical energy into electrical energy.

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Electrical Energy - The energy associated with electric charges and their movements.

Electricity - A form of energy characterized by the presence and motion of elementary charged particles generated by friction, induction, or chemical change.
See our brief sections on: Electricity and Electricity Milestones.

Electricity Generation - The process of producing electric energy or the amount of electric energy produced by transforming other forms of energy, commonly expressed in kilowatthours (kWh) or megawatthours (MWh).

Electric Motor - a device that takes electrical energy and converts it into mechanical energy to turn a shaft.

Electric Power - The amount of energy produced per second. The power produced by an electric current.

Electrochemistry - The branch of chemistry that deals with the chemical changes produced by electricity and the production of electricity by chemical changes.

Electromagnetic - Having to do with magnetism produced by an electric current.

Electromagnetic Energy - Energy that travels in waves, such as ultra-violet radiation. It can be thought of as a combination of electric and magnetic energy.

Electromagnetic Waves - Radiation that consists of traveling waves of electric and magnetic disturbances. X-rays, light rays and radio waves are among the many kinds of electromagnetic waves.

Electron - A subatomic particle with a negative electric charge. Electrons form part of an atom and move around its nucleus.

Element - Any substance that cannot be separated into different substances. All matter is composed of elements.

Emission - A discharge or something that is given off; generally used in regard to discharges into the air. Or, releases of gases to the atmosphere from some type of human activity (cooking, driving a car, etc). In the context of global climate change, they consist of greenhouse gases (e.g., the release of carbon dioxide during fuel combustion). Learn more about Greenhouse Gas Emissions on EIA's main website (for grown-ups).

Energy - The ability to do work or the ability to move an object. Electrical energy is usually measured in kilowatthours (kWh), while heat energy is usually measured in British thermal units (Btu).
See our brief sections on What's Energy? and General Energy Milestones,

Energy Consumption - The use of energy as a source of heat or power or as a raw material input to a manufacturing process.

Energy Efficiency - Refers to activities that are aimed at reducing the energy used by substituting technically more advanced equipment, typically without affecting the services provided. Examples include high-efficiency appliances, efficient lighting programs, high-efficiency heating, ventilating and air conditioning (HVAC) systems or control modifications, efficient building design, advanced electric motor drives, and heat recovery systems.

Ethanol - A colorless liquid that burns to produce water and carbon dioxide. The vapor forms an explosive mixture with air and may be used as a fuel in internal combustion engines.
See our brief sections on: Ethanol and Ethanol Milestones.

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Federal Energy Regulatory Agency(FERC) - The Federal government agency that regulates and oversees energy industries in the economic, environmental, and safety interests of the American public.

Filament - The fine metal wire in a light bulb that glows when heated by an electric current.

Fission - The splitting apart of atoms. This splitting releases large amounts of energy and one or more neutrons. Nuclear power plants split the nuclei of uranium atoms in a process called fission. See our section on Nuclear Energy.

Flat-Plate Solar Connector - A device designed to capture the suns energy and produce low temperature heat energy. They are commonly used as collectors in solar heating systems.

Flow - To move or run smoothly with unbroken continuity, as in the manner characteristic of a fluid.

Force - Something which changes the state of rest or motion of something.

Fossil Fuels - Fuels (coal, oil, natural gas, etc.) that result from the compression of ancient plant and animal life formed over millions of years.
See our brief sections on:

Fuel - Any material that can be burned to make energy.
See our brief sections on: Fuels and Fuel Milestones.

Fuel Cycle - The entire set of stages involved in the utilization of fuel, including extraction, transformation, transportation, and combustion.

Fuel Oil - An oil that is used for fuel and that usually ignites at a higher temperature than kerosene.

Furnace - An enclosed structure in which heat is produced for the purpose of heating a house or a building.

Fusion - When the nuclei of atoms are combined or "fused" together. The sun combines the nuclei of hydrogen atoms into helium atoms in a process called fusion. Energy from the nuclei of atoms, called "nuclear energy" is released from fusion. See the Scientific Forms of Energy.

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Gallon - A measure of volume equal to 4 quarts (231 cubic inches). One barrel equals 42 gallons.
Also see our How Big is a Barrel? and Energy Calculator.

Gas - (1) A non-solid, non-liquid (as hydrogen or air) substance that has no fixed shape and tends to expand without limit. (2) A state of matter in which the matter concerned occupies the whole of its container irrespective of its quantity. Includes natural gas, coke-oven gas, blast furnace gas, and refinery gas.

Gasoline - A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in spark-ignition engines.
See our brief section on: Transportation Milestones.

Gas To Liquids (GTL) - A process that combines the carbon and hydrogen elements in natural gas molecules to make synthetic liquid petroleum products, such as diesel fuel.

Gas Turbine Plant - A plant in which the prime mover is a gas turbine. A gas turbine consists typically of an axial-flow air compressor and one or more combustion chambers where liquid or gaseous fuel is burned and the hot gases are passed to the turbine and where the hot gases expand drive the generator and are then used to run the compressor.

Generator - A device that turns mechanical energy into electrical energy. The mechanical energy is sometimes provided by an engine or turbine.

Generating Capacity - The amount of electrical power a power plant can produce.

Geothermal Energy - The heat energy that is produced by natural processes inside the earth. It can be taken from hot springs, reservoirs of hot water deep below the ground, or by breaking open the rock itself.
See our brief sections on: Geothermal Energy and Geothermal Energy Milestones.

Global Warming - An increase in the near surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is today most often used to refer to the warming some scientists predict will occur as a result of increased anthropogenic emissions of greenhouse gases.

Gravity - The natural force of attraction of the mass of a heavenly body (as the earth) for bodies at or near its surface.

Greenhouse Effect - The effect of the Earth's atmosphere, due to certain gases, in trapping heat from the sun; the atmosphere acts like a greenhouse. Learn more about the Greenhouse Effect on EIA's main website (for grown-ups).

Greenhouse Emissions - Waste gases given off by industrial and power plants, automobiles and other processes. Learn more about Greenhouse Gas Emissions on EIA's main website (for grown-ups).

Greenhouse Gases - Gases that trap the heat of the sun in the Earth's atmosphere, producing the greenhouse effect. The two major greenhouse gases are water vapor and carbon dioxide. Lesser greenhouse gases include methane, ozone, chlorofluorocarbons, and nitrogen oxides. Learn more about Greenhouse Gas Emissions on EIA's main website (for grown-ups).

Green Pricing - In the case of renewable electricity, green pricing represents a market solution to the various problems associated with regulatory valuation of the nonmarket benefits of renewables. Green pricing programs allow electricity customers to express their willingness to pay for renewable energy development through direct payments on their monthly utility bills.

Grid - The layout of an electrical distribution system.

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Heat Content - The gross heat content is the number of British thermal units (Btu) produced by the combustion, of a volume of gas under certain with air of the same temperature and pressure as the gas, when the products of combustion are cooled to the initial temperature of gas and air and when the water formed by combustion is condensed to the liquid state.

Heat Exchanger - Any device that transfers heat from one fluid (liquid or gas) to another or to the environment.

Heating Equipment - Any equipment designed and/or specifically used for heating ambient air in an enclosed space. Common types of heating equipment include: central warm air furnace, heat pump, plug-in or built-in room heater, boiler for steam or hot water heating system, heating stove, and fireplace.

Heliostat - Flat sun-tracking mirrors used to reflect and concentrate the suns' energy onto a central receiver tower.

Horsepower - A unit for measuring the rate of work (or power) equivalent to 33,000 foot-pounds per minute or 746 watts.

Hydroelectric Power Plant - A power plant that uses moving water to power a turbine generator to produce electricity.

Hydrogen - A colorless, odorless, highly flammable gaseous element. It is the lightest of all gases and the most abundant element in the universe, occurring chiefly in combination with oxygen in water and also in acids, bases, alcohols, petroleum, and other hydrocarbons.

Hydropower - Energy that comes from moving water.
See our brief sections on: Water Energy.

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Incandescent Light Bulb - An incandescent bulb is a type of electric light in which light is produced by a filament heated by electric current. The most common example is the type you find in most table and floor lamps. In commercial buildings, incandescent lights are used for display lights in retail stores, hotels and motels. This includes the very small, high-intensity track lights used to display merchandise or provide spot illumination in restaurants.

Induction - The process of producing an electrical or magnetic effect through the influence of a nearby magnet, electric current, or electrically charged body.

Industrial Sector (of the Economy) - The part of the economy having to do with the production of goods. The industrial sector is made up of factories, power plants, etc.

Inertia - A property of matter by which it remains at rest or in uniform motion in the same straight line unless acted upon by some outside force.

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Joule - A metric unit for measuring work and energy, named after James Joule. It is equal to the work done when a one ampere current is passed through a resistance of one ohm for one second. See our Energy Calculator.

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Kerosene - A thick oil obtained from petroleum and used as a fuel and solvent.

Kilowatt - A unit of power, usually used for electric power or to energy consumption (use). A kilowatt equals 1000 watts. See our brief section on Measuring Electricity and our Energy Calculator.

Kilowatthour(kWh) - A measure of electricity defined as a unit of work or energy, measured as 1 kilowatt (1,000 watts) of power expended for 1 hour. One kWh is equivalent to 3,412 Btu or 3.6 million joules.

Kinetic - The energy of a body which results from its motion.

Kinetic Theory of Energy - The theory that the minute particles of all matter are in constant motion and that the temperature of a substance depends upon the velocity (speed) of the motion.

Kinetic Theory of Gases - The theory that physical properties of a gas are due to the rapid motion in a straight line of its molecules, to their impacts against each other and the walls of the container, and to weak attraction forces between the molecules.

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Light - Radiant electromagnetic energy that an observer can see.

Liquefied Petroleum Gas (LPG) -A group of hydrocarbon-based gases derived from crude oil refining or natural gas fractionation. They include ethane, ethylene, propane, propylene, normal butane, butylene, isobutane, and isobutylene. For convenience of transportation, these gases are liquefied through pressurization.

Load - The power and energy requirements of users on the electric power system in a certain area or the amount of power delivered to a certain point.

Longwall Mining - An automated form of underground coal mining characterized by high recovery and extraction rates, feasible only in relatively flat-lying, thick, and uniform coalbeds. A high-powered cutting machine is passed across the exposed face of coal, shearing away broken coal, which is continuously hauled away by a floor-level conveyor system. Longwall mining extracts all machine-minable coal between the floor and ceiling within a contiguous block of coal, known as a panel, leaving no support pillars within the panel area. Panel dimensions vary over time and with mining conditions but currently average about 900 feet wide (coal face width) and more than 8,000 feet long (the minable extent of the panel, measured in direction of mining). Longwall mining is done under movable roof supports that are advanced as the bed is cut. The roof in the mined-out area is allowed to fall as the mining advances.

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Magnet - Any piece of iron, steel, etc., that has the property of attracting iron or steel.

Mechanical Energy - The energy of motion used to perform work.

Mechanical Power - The power produced by motion.

Megawatt - A unit of electrical power equal to 1000 kilowatts or one million watts. See our Energy Calculator.

Mercaptan - An organic chemical compound that has a sulfur like odor that is added to natural gas before distribution to the consumer, to give it a distinct, unpleasant odor (smells like rotten eggs). This serves as a safety device by allowing it to be detected in the atmosphere, in cases where leaks occur.

Methane -A colorless, flammable, odorless hydrocarbon gas (CH4) which is the major component of natural gas. It is also an important source of hydrogen in various industrial processes. Methane is a greenhouse gas.

Miles Per Gallon (MPG) - A measure of vehicle fuel efficiency. MPG is computed as the ratio of the total number of miles traveled by a vehicle to the total number of gallons consumed.
Also see our Energy Calculator.

Mobile Home - A trailer that is used as a permanent dwelling.

Molecule - Particles that normally consist of two or more atoms joined together. An example is a water molecule that is made up of two hydrogen atoms and one oxygen atom.

Multifamily Dwellings - Apartment building and condominiums.

Municipal Solid Waste (MSW) - Residential solid waste and some nonhazardous commercial, institutional, and industrial wastes.
See our brief sections: Garbage, and MSW Milestones.

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Natural Gas - An odorless, colorless, tasteless, non-toxic clean-burning fossil fuel. It is usually found in fossil fuel deposits and used as a fuel.
See our brief sections on: Natural Gas and Natural Gas Milestones.

Natural Gas Hydrates - Solid, crystalline, wax-like substances composed of water, methane, and usually a small amount of other gases, with the gases being trapped in the interstices of a water-ice lattice. They form beneath permafrost and on the ocean floor under conditions of moderately high pressure and at temperatures near the freezing point of water.

Natural Gas Liquids (NGL) - Substances that can be processed as liquids out of natural gas by absorption or condensation.

Non-biogenic waste:  Waste made from fossil materials or materials of non-biological origin, such as plastics, and tire-derived fuels.

Nonconcentrator System - A type of solar energy system that does not rely on special devices to concentrate the sun's radiation while collecting it.

Nonrenewable - Fuels that cannot be easily made or "renewed." We can use up nonrenewable fuels. Oil, natural gas, and coal are nonrenewable fuels.
See our brief sections on Nonrenewable Energy.

Nuclear Energy - Energy that comes from splitting atoms of radioactive materials, such as uranium.
See our brief sections on: Nuclear Energy, Nuclear Power Milestones and Electricity Milestones.

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Offshore - The geographic area that lies seaward of the coastline. In general, the coastline is the line of ordinary low water along with that portion of the coast that is in direct contact with the open sea or the line marking the seaward limit of inland water.

Offshore Reserves and Production - Unless otherwise dedicated, energy source reserves and production that are in either state or Federal domains, located seaward of the coastline.

Ohm - The unit of resistance to the flow of an electric current.

Oil - The raw material that petroleum products are made from. A black liquid fossil fuel found deep in the Earth. Gasoline and most plastics are made from oil.
See our brief sections on: Oil and Oil Milestones.

OPEC - The Organization of Petroleum Exporting Countries organized for the purpose of negotiating with oil companies on matters of oil production, prices, and future concession rights. Current members (as of the date of writing this definition) are Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, the United Arab Emirates, and Venezuela. See OPEC's site at http://www.opec.org for more information.

Organic Waste - Waste material of animal or plant origin.

Outer Continental Shelf - Offshore Federal domain.

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Parabolic Trough - A type of solar concentrator collector that has a linear parabolic shaped reflector that focuses the sun’s radiation on a receiver at the focus of the reflector.

Passive Heating System - A means of capturing, storing, and using heat from the sun.

Peak Load Plant- A plant usually housing old, low-efficiency steam units, gas turbines, diesels, or pumped-storage hydroelectric equipment normally used during the peak-load periods.

Penstock - A large pipe which carries moving water from the reservoir to a turbine generator in a hydropower plant.

Petrochemicals - Organic and inorganic petroleum compounds and mixtures that include but are not limited to organic chemicals, cyclic intermediates, plastics and resins, synthetic fibers, elastomers, organic dyes, organic pigments, detergents, surface active agents, carbon black, and ammonia.

Periodic Table - Table of all known elements in a meaningful pattern. See Periodic Table.

Petroleum - Generally refers to crude oil or the refined products obtained from the processing of crude oil (gasoline, diesel fuel, heating oil, etc.) Petroleum also includes lease condensate, unfinished oils, and natural gas plant liquids.
See our brief sections on: Petroleum and Petroleum Milestones.

Photon - A particle of light that acts as an individual unit of energy.

Photosynthesis - The process by which green plants make food (carbohydrates) from water and carbon dioxide, using the energy in sunlight.

Photovoltaic Cells - A device, usually made from silicon, which converts some of the energy from light (radiant energy) into electrical energy. Another name for a solar cell.
See our brief sections on: Photovoltaics and Photovoltaic Milestones.

Photovoltaic Conversion - The process by which radiant (light) energy is changed into electrical energy.

Pipeline, Distribution - A pipeline that conveys gas from a transmission pipeline to its ultimate consumer.

Plasma - A high-temperature, ionized gas composed of electrons and positive ions in such number that it is electrically neutral.

Power - The rate at which energy is transferred. Electrical energy is usually measured in watts. Also used for a measurement of capacity.

Power Degradation - The loss of power when electricity is sent over long distances.

Power-Generating Efficiency - The percentage of the total energy content of a power plant’s fuel which is converted into electric energy. The remaining energy is lost to the environment as heat.

Power Plant - A facility where power, especially electricity, is generated.

Pressurized Water Reactor - A reactor in which water, heated by nuclear energy, is kept a high pressure to prevent the water from boiling. Steam is then generated in a secondary coolant loop.

Prime Mover - The engine, turbine, water wheel, or similar machine that drives an electric generator; or, for reporting purposes, a device that converts energy to electricity directly (i.e. photovoltaic solar and fuel cells).

Propane (C3H8) - A normally gaseous straight-chain hydrocarbon. It is a colorless paraffinic gas that boils at a temperature of -43.67 degrees Fahrenheit. It is extracted from natural gas or refinery gas streams.
See our brief sections on Propane.

Production, Oil and Gas - The lifting of oil and gas to the surface and gathering, treating, field processing (as in the case of processing gas to extract liquid hydrocarbons), and field storage.

Pumped Storage - a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations.

Public Utility Regulatory Policies Act (PURPA) - A law passed by Congress in 1978 to promote more efficient use of fossil fuels and greater use of renewable energy for generating electricity. A renewable or cogeneration facility that qualifies for PURPA benefits is called a Qualifying Facility (QF).  Utility companies buy the electricity from QFs at the “avoided cost.”  This is the cost it would take for the utility company to generate the amount of electricity the QF produces.

Pyrolysis - The decomposition of biomass at very high temperatures. It results in a mixture of solids (char), liquids (oxygenated oils), and gases (methane, carbon monoxide, and carbon dioxide).

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Quadrillion Btu: One quadrillion (1015= 10 to the 15th power) British thermal units (Btu).
See British Thermal Unit (Btu) and our section on using Btu to compare energy and our Converting Units.

Qualified Facilty(QF)- A renewable or cogeneration facility that qualifies for PURPA benefits is called a Qualifying Facility (QF).

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R-Value - A measure of a material's resistance to heat flow in units of Fahrenheit degrees x hours x square feet per Btu. The higher the R-value of a material, the greater its insulating capability.

Radiant Energy - Any form of energy radiating from a source in waves.

Radiation - Any high-speed transmission of energy in the form of particles or electromagnetic waves.

Radioactive Element - An element whose atoms have unstable nuclei that stabilizes itself by giving off radiation.

Radioactive Waste - Materials left over from making nuclear energy. Radioactive waste can harm people and the environment if it is not stored safely.

Radioactivity - The property possessed by some elements, such as uranium, of giving off alpha, beta, or gamma rays.

Reactor Core - Part of a nuclear power station - the structure inside which fission occurs in millions of atomic nuclei, producing huge amounts of heat energy.

Receiver Panel (Solar) - A panel that contains a battery of solar cells.

Recycling - The process of converting materials that are no longer useful as designed or intended into a new product.

Refinery - An industrial plant that heats crude oil (petroleum) so that is separates into chemical components, which are then made into more useful substances.

Refined Petroleum Products - Refined petroleum products include but are not limited to gasoline, kerosene, distillates (including No. 2 fuel oil), liquefied petroleum gas, asphalt, lubricating oils, diesel fuels, and residual fuels.

Refrigeration - To make or keep food cold or cool by using a refrigerator.

Renewable Energy Sources - Fuels that can be easily made or "renewed." We can never use up renewable fuels. Types of renewable fuels are hydropower (water), solar, wind, geothermal, and biomass. .

Residential Sector (of the Economy) - The part of the economy having to do with the places people stay or live. The residential sector is made up of homes, apartments, condominiums, etc.

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Semiconductor - Any material that has a limited capacity for conducting an electric current. Semiconductors are crystalline solids, such as silicon, that have an electrical conductivity between that of a conductor and an insulator.

Shaft mine - A mine that reaches the coal bed by means of a vertical shaft.

Short ton - A unit of weight equal to 2,000 pounds, often used to measure coal. See our Energy Calculator.

Solar Cell - An electric cell which changes radiant energy from the sun into electrical energy by the photovoltaic process.

Solar Dish - A device that receives radiation collected by motorized collectors which track the sun. The collectors focus the radiation the energy at a focal point of the dish.

Solar Energy - The radiant energy of the sun, which can be converted into other forms of energy, such as heat or electricity.
See our brief sections on: Solar Energy and Photovoltaic.

Solar Power Tower - The conceptual method of producing electrical energy from solar rays. It involved the focusing of a large number of solar rays on a single source (boiler), usually located on an elevated tower, to produce high temperatures. A fluid located in or passed through the source changes into steam and used in a turbine generator to produce electrical energy.

Solar spectrum - The total distribution of electromagnetic radiation emanating from the sun.

Solar Thermal Heating System - Systems using concentrating collectors to focus the sun's radiant energy onto or into receivers to produce heat.

Space Heating - The use of energy to generate heat for warmth in housing units using space-heating equipment. The equipment could be the main space-heating equipment or secondary space-heating equipment.

Spectrum of Electromagnetic Radiation - The name that scientists give to a bunch of types of radiation when they want to talk about them as a group. The types of radiation include the full range of frequencies, from radio waves to gamma waves, which characterize light.

Spent Fuel - Irradiated fuel that is permanently discharged from a nuclear reactor. Except for possible reprocessing, this fuel must eventually be removed from its temporary storage location at the reactor site and placed in a permanent repository. Spent fuel is typically measured either in metric tons of heavy metal (i.e., only the heavy metal content of the spent fuel is considered) or in metric tons of initial heavy metal (essentially, the initial mass of the fuel before irradiation). The difference between these two quantities is the weight of the fission products.
See our brief sections on: Nuclear Energy, Nuclear Power Milestones and Electricity Milestones.

Steam - Water in vapor form; used as the working fluid in steam turbines and heating systems.

Steam Generator - A generator in which the prime movers (turbines) are powered by steam.

Superconductivity - The abrupt and large increase in electrical conductivity exhibited by some metals as the temperature approaches absolute zero.

Surface Mine - A coal-producing mine that is usually within a few hundred feet of the surface. Earth above or around the coal (overburden) is removed to expose the coal bed, which is then mined with surface excavation equipment, such as draglines, power shovels, bulldozers, loaders, and augers. It may also be known as an area, contour, open-pit, strip, or auger mine.

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Tank Farm - An installation used by trunk and gathering pipeline companies, crude oil producers, and terminal operators (except refineries) to store crude oil.

Tanker and Barge - Vessels that transport crude oil or petroleum products.

Tesla Coil - A device for producing a high-frequency, high-voltage electric current.

Thermal Energy - The total potential and kinetic energy associated with the random motions of the molecules of a material.

Thermostat - A device that adjusts the amount of heating and cooling produced and/or distributed by automatically responding to the temperature in the environment.

Transformer - A device which converts the generator's low-voltage electricity to higher-voltage levels for transmission to the load center, such as a city or factory.

Transmission (Electric) - The movement or transfer of electric energy over an interconnected group of lines and associated equipment between points of supply and points at which it is transformed for delivery to consumers or is delivered to other electric systems. Transmission is considered to end when the energy is transformed for distribution to the consumer.

Transmission Line - A set of conductors, insulators, supporting structures, and associated equipment used to move large quantities of power at high voltage, usually over long distances between a generating or receiving point and major substations or delivery points.

Transmission System (Electric) - An interconnected group of electric transmission lines and associated equipment for moving or transferring electric energy in bulk between points of supply and points at which it is transformed for delivery over the distribution system lines to consumers or is delivered to other electric systems.

Turbine - A device which blades, which is turned by a force, e.g. that of wind, water , or high pressure steam. The mechanical energy of the spinning turbine is converted into electricity by a generator.

)Transportation Sector (of the Economy - The part of the economy having to do with the how people and goods are transported (moved) from place to place.. The transportation sector is made up of automobiles, airplanes, trucks, and ships. trains, etc.
See our brief section on: Transportation and Transportation Milestones.

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Underground Mine - A mine where coal is produced by tunneling into the earth to the coal bed, which is then mined with underground mining equipment such as cutting machines and continuous, long wall, and short wall mining machines. Underground mines are classified according to the type of opening used to reach the coal, i.e., drift (level tunnel), slope (inclined tunnel), or shaft (vertical tunnel).

Uranium - A heavy, naturally-occurring, radioactive element.
See our brief sections on: Nuclear Energy, Nuclear Power Milestones and Electricity Milestones.

Uranium Fuel Cycle - The series of steps involved in supplying fuel for nuclear power reactors. It includes mining, refining, the making of fuel elements, their use in a reactor, chemical processing to recover spent (used) fuel, re-enrichment of the fuel material, and remaking into new fuel elements.

Utility Generation - Generation by electric systems engaged in selling electric energy to the public.

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Vehicle Fuel Consumption - Vehicle fuel consumption is computed as the vehicle miles traveled divided by the fuel efficiency reported in miles per gallon (MPG). Vehicle fuel consumption is derived from the actual vehicle mileage collected and the assigned MPGs obtained from EPA certification files adjusted for on-road driving. The quantity of fuel used by vehicles.

Volcanic Energy - Energy produced from volcanic action.
See our brief sections on: Geothermal Energy and Geothermal Energy Milestones.

Volt (V) - The volt is the International System of Units (SI) measure of electric potential or electromotive force. A potential of one volt appears across a resistance of one ohm when a current of one ampere flows through that resistance. Reduced to SI base units, 1 V = 1 kg times m2 times s-3 times A-1 (kilogram meter squared per second cubed per ampere).

Voltage - The difference in electrical potential between any two conductors or between a conductor and ground. It is a measure of the electric energy per electron that electrons can acquire and/or give up as they move between the two conductors.

Voltaic Electricity - Electricity produced by chemical action.

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Waste - Municipal solid waste, landfill gas, methane, digester gas, liquid acetonitrile waste, tall oil, waste alcohol, medical waste, paper pellets, sludge waste, solid byproducts, tires, agricultural byproducts, closed loop biomass, fish oil, and straw.

Waste Energy - Municipal solid waste, landfill gas, methane, digester gas, liquid acetonitrile waste, tall oil, waste alcohol, medical waste, paper pellets, sludge waste, solid byproducts, tires, agricultural byproducts, closed loop biomass, fish oil, and straw used as fuel.
See our brief sections on: Waste Energy , Waste Energy Milestones, and Waste-to-Energy Plant Visit.

Water Cycle - Water constantly moves through a vast global cycle, in which it evaporates from lakes and oceans, forms clouds, precipitates as rain or snow, then flows back to the ocean. The energy of this water cycle, which is driven by the sun, is tapped most efficiently with hydropower.

Water Heater - An automatically controlled, thermally insulated vessel designed for heating water and storing heated water at temperatures less than 180 degrees Fahrenheit.

Water Turbine - A turbine that uses water pressure to rotate its blades. Primarily used to power an electric generator.

Watt - A metric unit of power, usually used in electric measurements, which gives the rate at which work is done or energy used. See our section on Measuring Electricity.

Wavelength - The distance, measured in the direction of progression of a wave, from any given point to the next point in the same phase.

Well - A hole drilled in the earth for the purpose of (1) finding or producing crude oil or natural gas; or (2) producing services related to the production of crude or natural gas.

Wellhead - The point at which the crude (and/or natural gas) exits the ground.

Wind - The term given to any natural movement of air in the atmosphere. A renewable source of energy used to turn turbines to generate electricity.
See our brief sections on: Wind Energy and Wind Energy Milestones.

Wind Machine - Devices powered by the wind that produce mechanical or electrical power.

Wind Tower - Devices, some as tall as 120 feet, which lift wind turbine blades high above the ground to catch stronger wind currents.

Wood and Waste (as used at electric utilities) - Wood energy, garbage, bagasse (sugarcane residue), sewerage gas, and other industrial, agricultural, and urban refuse used to generate electricity for distribution.

Wood Energy - Wood and wood products used as fuel, including round wood (cord wood), limb wood, wood chips, bark, sawdust, forest residues, charcoal, pulp waste, and spent pulping liquor.

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Yellowcake: A natural uranium concentrate that takes its name from its color and texture. Yellowcake typically contains 70 to 90 percent U3O8 (uranium oxide) by weight. It is used as feedstock for uranium fuel enrichment and fuel pellet fabrication.
See a yellowcake picture.


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