A

• AAQS—Ambient Air Quality Standards
  National Ambient Air Quality Standards
  The National Ambient Air Quality Standards are standards established by the United States Environmental Protection Agency under authority of the Clean Air Act that apply for outdoor air throughout the country...
  
    (environment) (US)
• AAU—Assigned amount units
  Assigned amount units
  An Assigned Amount Unit is a tradable 'Kyoto unit' or 'carbon credit' representing an allowance to emit greenhouse gases comprising one metric tonne of carbon dioxide equivalents calculated using their Global Warming Potential....
  
   (measurement)
• ABT—Availability based tariff
  Availability based tariff
  Availability Based Tariff is a frequency based pricing mechanism for electric power. The ABT falls under electricity market mechanisms to charge and regulate power to achieve short term and long term network stability as well as incentives and dis-incentives to market participants against...
  
   (electricity)
• ABF—Aquatic Base Flow (Hydropower
  Hydropower
  Hydropower, hydraulic power, hydrokinetic power or water power is power that is derived from the force or energy of falling water, which may be harnessed for useful purposes. Since ancient times, hydropower has been used for irrigation and the operation of various mechanical devices, such as...
  
  ) (electricity)
• AC—Alternating current
  Alternating current
  In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
  
  
• ACA—Annual Charge Adjustment (electricity)
• Acc.—Accession countries (to the European Union) (government)
• ACE—Area Control Error (electricity)
• ACEEE—American Council for an Energy-Efficient Economy
  American Council for an Energy-Efficient Economy
  The American Council for an Energy-Efficient Economy, or ACEEE, is a nonprofit, 501 organization. Founded in 1980, ACEEE's mission is to advance energy efficiency as a fast, cheap, and effective means of meeting energy challenges...
  
  
• ACRS—Accelerated Cost Recovery System
  MACRS
  The Modified Accelerated Cost Recovery System is the current tax depreciation system in the United States. Under this system, the capitalized cost of tangible property is recovered over a specified life by annual deductions for depreciation. The lives are specified broadly in the Internal...
  
   (finance)
• ADITC—Accumulated Deferred Investment Tax Credit (policy)
• ADR—Asset Depreciation Range (finance)
  • —Alternative dispute resolution
    Alternative dispute resolution
    Alternative Dispute Resolution includes dispute resolution processes and techniques that act as a means for disagreeing parties to come to an agreement short of litigation. ADR basically is an alternative to a formal court hearing or litigation...
    
    
• AEP—American Electric Power
  American Electric Power
  American Electric Power is a major investor-owner electric utility in various parts of the United States. AEP ranks among the nation's largest generators of electricity, owning nearly 38,000 megawatts of generating capacity in the U.S...
  
   (electricity)
• AESO—Alberta Electric System Operator
  Alberta Electric System Operator
  The Alberta Electric System Operator, abbreviated AESO, is a not-for-profit entity responsible for the planning and operation of the Alberta Interconnected Electric System in a safe, reliable, and economical manner....
  
  
• AFE—Authority for Expenditure or Authorization for Expenditure
• AFUDC—allowance for funds used during construction
• AFV—Alternative fuel vehicle
  Alternative fuel vehicle
  An alternative fuel vehicle is a vehicle that runs on a fuel other than "traditional" petroleum fuels ; and also refers to any technology of powering an engine that does not involve solely petroleum...
  
  
• AGA—American Gas Association
  American Gas Association
  The American Gas Association , founded in 1918, is an American trade organization representing natural gas supply companies and others with an interest in the manufacturing of gas appliances as well as the production of gas...
  
  
• AGC—Automatic generation control
  Automatic generation control
  In an electric power system, automatic generation control is a system for adjusting the power output of multiple generators at different power plants, in response to changes in the load. Since a power grid requires that generation and load closely balance moment by moment, frequent adjustments to...
  
  
• AGD—Associated Gas Distributors (US)
• AIMA—Agricultural Impact Mitigation Agreement (US)
• ALJ—Administrative law judge
  Administrative law judge
  An administrative law judge in the United States is an official who presides at an administrative trial-type hearing to resolve a dispute between a government agency and someone affected by a decision of that agency. The ALJ is usually the initial trier of fact and decision maker...
  
  
• AMBO—Armenia, Macedonia, Bulgaria Oil pipeline
  AMBO pipeline
  AMBO pipeline is a planned oil pipeline from the Bulgarian Black Sea port of Burgas via the Republic of Macedonia to the Albanian Adriatic port of Vlorë.-History:The pipeline was proposed already in 1993...
  
  
• AMI—Advanced metering infrastructure
• AMR—Automated meter reading also known as Automatic Meter Reading
• AMRA—Automatic Meter Reading
  Automatic meter reading
  Automatic meter reading, or AMR, is the technology of automatically collecting consumption, diagnostic, and status data from water meter or energy metering devices and transferring that data to a central database for billing, troubleshooting, and analyzing.This technology mainly saves utility...
  
   Association
• ANGTA—Alaskan Natural Gas Transportation Act of 1977 to build the Alaska gas pipeline
• ANGTS—Alaskan Natural Gas Transportation System
• ANSI—American National Standards Institute
  American National Standards Institute
  The American National Standards Institute is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organization also coordinates U.S. standards with international...
  
  
• AOS—Authorized Overrun Service
• APA—Administrative Procedure Act
  Administrative Procedure Act
  The Administrative Procedure Act , , is the United States federal law that governs the way in which administrative agencies of the federal government of the United States may propose and establish regulations. The APA also sets up a process for the United States federal courts to directly review...
  
  
  • —Alaska Power Administration
• APE—Area of potential effect (electricity)
• API—American Petroleum Institute
  American Petroleum Institute
  The American Petroleum Institute, commonly referred to as API, is the largest U.S trade association for the oil and natural gas industry...
  
   (oil)
• APPA—American Public Power Association (electricity)
• APR—Actual peak reduction (e.g. in demand response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   systems) (electricity)
• AQCR—Air Quality Control Region (US) (environment)
• ARA—(in shipping) ports of Amsterdam
  Amsterdam
  Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...
  
   – Rotterdam
  Rotterdam
  Rotterdam is the second-largest city in the Netherlands and one of the largest ports in the world. Starting as a dam on the Rotte river, Rotterdam has grown into a major international commercial centre...
  
   – Antwerp  (oil)
• ASCC—Alaskan System Coordination Council
• ASE—Alliance to Save Energy
  Alliance to Save Energy
  The Alliance to Save Energy is a coalition consisting largely of industrial, technological, and energy corporations. The Alliance states that its mission is to "support energy efficiency as a cost-effective energy resource under existing market conditions and advocate energy-efficiency policies...
  
  
• ASTM—American Society for Testing and Materials
• ATC—Available transfer capability
• AVR—Automatic Voltage Regulator (electricity)

B

• BA—Balancing Authority
• BA—Biological Assessment
• BACT—Best Available Control Technology
  Best Available Control Technology
  Best available control technology is a pollution control standard mandated by the United States Clean Air Act. The U.S. Environmental Protection Agency determines what air pollution control technology will be used to control a specific pollutant to a specified limit...
  
  
• BBL/D—Barrel per day
• BBL/SD—Barrel per day, on stream days
• BBL—barrel (42 gallons)
  • —Balgzand Bacton Line (BBL Pipeline)
    BBL Pipeline
    The BBL Pipeline is the first natural gas pipeline between the Netherlands and the United Kingdom.-History:Laying the pipeline between the North Holland compressor station at Grasweg in Anna Paulowna and Bacton Gas Terminal started on 14 July 2006...
    
    
• BCD—Barrel per day, on calendar days
• BCF—billion cubic feet
• BCP—Blackstart
  Blackstart
  The Blackstart, Cercomela melanura, is a chat found in desert regions in North Africa, the Middle East and the Arabian Peninsula.It is a 14–16 cm long bird named for its black tail, which is frequently fanned; the rest of its plumage is bluish-grey or grey-brown...
  
   Capability Plan
• BES—Bulk electric system (Electricity transmission)
• BfP—Bureau Fédéral du Plan
  Federal Planning Bureau
  The Federal Planning Bureau is a Belgian independent public agency. It makes studies and projections on economic, social and environmental policy issues and on their integration within the context of sustainable development...
  
   (Belgium). (Has responsibilities over economic, social and environmental policy
• BIA—Bureau of Indian Affairs
  Bureau of Indian Affairs
  The Bureau of Indian Affairs is an agency of the federal government of the United States within the US Department of the Interior. It is responsible for the administration and management of of land held in trust by the United States for Native Americans in the United States, Native American...
  
   (US)
• bl—Barrel
  Barrel
  A barrel or cask is a hollow cylindrical container, traditionally made of vertical wooden staves and bound by wooden or metal hoops. Traditionally, the barrel was a standard size of measure referring to a set capacity or weight of a given commodity. A small barrel is called a keg.For example, a...
  
  
• BLM—Bureau of Land Management
  Bureau of Land Management
  The Bureau of Land Management is an agency within the United States Department of the Interior which administers America's public lands, totaling approximately , or one-eighth of the landmass of the country. The BLM also manages of subsurface mineral estate underlying federal, state and private...
  
   of United States Department of the Interior
  United States Department of the Interior
  The United States Department of the Interior is the United States federal executive department of the U.S. government responsible for the management and conservation of most federal land and natural resources, and the administration of programs relating to Native Americans, Alaska Natives, Native...
  
  
• BLS—Bureau of Labor Statistics
  Bureau of Labor Statistics
  The Bureau of Labor Statistics is a unit of the United States Department of Labor. It is the principal fact-finding agency for the U.S. government in the broad field of labor economics and statistics. The BLS is a governmental statistical agency that collects, processes, analyzes, and...
  
   of United States Department of Labor
  United States Department of Labor
  The United States Department of Labor is a Cabinet department of the United States government responsible for occupational safety, wage and hour standards, unemployment insurance benefits, re-employment services, and some economic statistics. Many U.S. states also have such departments. The...
  
  
• BOE—Barrel of oil equivalent
  Barrel of oil equivalent
  The barrel of oil equivalent is a unit of energy based on the approximate energy released by burning one barrel of crude oil. The US Internal Revenue Service defines it as equal to 5.8 × 106 BTU...
  
   (international)
• BPA—Bonneville Power Administration
  Bonneville Power Administration
  The Bonneville Power Administration is an American federal agency based in the Pacific Northwest. BPA was created by an act of Congress in 1937 to market electric power from the Bonneville Dam located on the Columbia River and to construct facilities necessary to transmit that power...
  
   (US)
• BPL—Broadband over power line
• BPS—Bulk Power System (Electricity transmission)
• BTU—British thermal unit
  British thermal unit
  The British thermal unit is a traditional unit of energy equal to about 1055 joules. It is approximately the amount of energy needed to heat of water, which is exactly one tenth of a UK gallon or about 0.1198 US gallons, from 39°F to 40°F...
  
  (s)
• BTX—from BTX process, a mixture of benzene
  Benzene
  Benzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....
  
  , toluene
  Toluene
  Toluene, formerly known as toluol, is a clear, water-insoluble liquid with the typical smell of paint thinners. It is a mono-substituted benzene derivative, i.e., one in which a single hydrogen atom from the benzene molecule has been replaced by a univalent group, in this case CH3.It is an aromatic...
  
  , xylene
  Xylene
  Xylene encompasses three isomers of dimethylbenzene. The isomers are distinguished by the designations ortho- , meta- , and para- , which specify to which carbon atoms the two methyl groups are attached...
  
   (oil)
• BuRec—United States Bureau of Reclamation
  United States Bureau of Reclamation
  The United States Bureau of Reclamation , and formerly the United States Reclamation Service , is an agency under the U.S...
  
   (government)
• BWR—Boiling water reactor
  Boiling water reactor
  The boiling water reactor is a type of light water nuclear reactor used for the generation of electrical power. It is the second most common type of electricity-generating nuclear reactor after the pressurized water reactor , also a type of light water nuclear reactor...
  
   (nuclear)

C

• C&I—Commercial and industrial customers (Electricity transmission)
• CA—Carbon Abatement- increasing carbon neutral
  Carbon neutral
  Carbon neutrality, or having a net zero carbon footprint, refers to achieving net zero carbon emissions by balancing a measured amount of carbon released with an equivalent amount sequestered or offset, or buying enough carbon credits to make up the difference...
  
  ity
  • —Control area (EU) – The portion of the generation and transmission system controlled by a single transmission system operator. (See also TSO
    Transmission system operator
    File:Electricity grid simple- North America.svg|thumb|380px|right|Simplified diagram of AC electricity distribution from generation stations to consumersrect 2 243 235 438 Power stationrect 276 317 412 556 Transformer...
    
    ).
• CAA—Clean Air Act
  Clean Air Act
  A Clean Air Act is one of a number of pieces of legislation relating to the reduction of airborne contaminants, smog and air pollution in general. The use by governments to enforce clean air standards has contributed to an improvement in human health and longer life spans...
  
   (US)
• CAEM—Center for the Advancement of Energy Markets (US)
• CAFE—Corporate Average Fuel Economy
  Corporate Average Fuel Economy
  The Corporate Average Fuel Economy are regulations in the United States, first enacted by the U.S. Congress in 1975, and intended to improve the average fuel economy of cars and light trucks sold in the US in the wake of the 1973 Arab Oil Embargo...
  
   standards (US)
• CAISO—California Independent System Operator Corporation, a Regional Transmission Organization
  Regional Transmission Organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
  . (US)
• CAP—Capacity market programs
• CAPM—Capital asset pricing model
  Capital asset pricing model
  In finance, the capital asset pricing model is used to determine a theoretically appropriate required rate of return of an asset, if that asset is to be added to an already well-diversified portfolio, given that asset's non-diversifiable risk...
  
  
• CARB—California Air Resources Board
  California Air Resources Board
  The California Air Resources Board, also known as CARB or ARB, is the "clean air agency" in the government of California. Established in 1967 in the Mulford-Carrell Act, combining the Bureau of Air Sanitation and the Motor Vehicle Pollution Control Board, CARB is a department within the...
  
  
• CBL—Customer Baseline Load
• CBM—Capacity Benefit Margin
• CBOB—Conventional Gasoline Blendstock for Oxygenate
  Oxygenate
  Oxygenated chemical compounds contain oxygen as a part of their chemical structure. The term usually refers to oxygenated fuels. Oxygenates are usually employed as gasoline additives to reduce carbon monoxide that is created during the burning of the fuel....
  
   Blending (Motor Gasoline Blending Component)
• CC—Combined cycle
  Combined cycle
  In electric power generation a combined cycle is an assembly of heat engines that work in tandem off the same source of heat, converting it into mechanical energy, which in turn usually drives electrical generators...
  
   see also CCPP and CCGT
• CC—Combined cycle
  Combined cycle
  In electric power generation a combined cycle is an assembly of heat engines that work in tandem off the same source of heat, converting it into mechanical energy, which in turn usually drives electrical generators...
  
   Gas turbine
  Gas turbine
  A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between....
  
   electricity generator
• CCIP—Centre for Critical Infrastructure Protection
  Centre for Critical Infrastructure Protection
  The Centre for Critical Infrastructure Protection is an organisational unit of New Zealand's Government Communications Security Bureau...
  
   (New Zealand)
• CCLIP—Conditional Credit Line for Investment Projects
• CCPG—Colorado Coordinated Planning Group
• CCPP—Combined cycle
  Combined cycle
  In electric power generation a combined cycle is an assembly of heat engines that work in tandem off the same source of heat, converting it into mechanical energy, which in turn usually drives electrical generators...
  
   power plant
• CD—Contract Demand
• CDD—Cooling degree day
  Heating degree day
  Heating degree day is a measurement designed to reflect the demand for energy needed to heat a home or business. It is derived from measurements of outside air temperature. The heating requirements for a given structure at a specific location are considered to be directly proportional to the...
  
  , a qualitative index used to reflect the demand for energy to cool a business
• CDM—Clean Development Mechanism
  Clean Development Mechanism
  The Clean Development Mechanism is one of the "flexibility" mechanisms defined in the Kyoto Protocol . It is defined in Article 12 of the Protocol, and is intended to meet two objectives: to assist parties not included in Annex I in achieving sustainable development and in contributing to the...
  
  
• CEA—Country Environmental Analysis
• CEC—California Energy Commission
  California Energy Commission
  The California Energy Commission is California’s primary energy policy and planning agency. Created in 1974 and headquartered in Sacramento, the Commission has responsibility for activities that include forecasting future energy needs, promoting energy efficiency through appliance and building...
  
  
  • —Commission for Environmental Cooperation
    Commission for Environmental Cooperation
    The Commission for Environmental Cooperation was established by Canada, Mexico, and the United States to implement the North American Agreement on Environmental Cooperation , the environmental side accord to the North American Free Trade Agreement...
    
    
  • —Council of the European Communities
• CEEC—Central
  Central Europe
  Central Europe or alternatively Middle Europe is a region of the European continent lying between the variously defined areas of Eastern and Western Europe...
  
   and Eastern Europe
  Eastern Europe
  Eastern Europe is the eastern part of Europe. The term has widely disparate geopolitical, geographical, cultural and socioeconomic readings, which makes it highly context-dependent and even volatile, and there are "almost as many definitions of Eastern Europe as there are scholars of the region"...
  
  an Countries
• CEP—Country Environmental Profile
  • —Clean Energy Partnership
    Clean Energy Partnership
    Clean Energy Partnership is a joint project for world's most versatile hydrogen demonstration. It is aiming for emission-free mobility and has several hydrogen stations.As of May 2010 the CEP is a consortium of thirteen partners:...
    
    , a joint hydrogen-project in Europe.
• CEPS—Centre for European Policy Studies
  Centre for European Policy Studies
  The Centre for European Policy Studies is a think tank based in Brussels, Belgium that undertakes research "leading to solutions to the challenges facing Europe today"...
  
  
• CEPII—Centre d'Etudes Prospectives et d'Informations Internationales Economics think tank
• CEQ—Council on Environmental Quality
  Council on Environmental Quality
  The Council on Environmental Quality is a division of the Executive Office of the President that coordinates federal environmental efforts in the United States and works closely with agencies and other White House offices in the development of environmental and energy policies and initiatives...
  
  
• CER—Certified Emission Reduction
  Certified Emission Reduction
  Certified Emission Reductions are a type of emissions unit issued by the Clean Development Mechanism Executive Board for emission reductions achieved by CDM projects and verified by a DOE under the rules of the Kyoto Protocol...
  
  
• CERA—Cambridge Energy Research Associates
  Cambridge Energy Research Associates
  Cambridge Energy Research Associates is a consulting company in the United States that specializes in advising governments and private companies on energy markets, geopolitics, industry trends, and strategy...
  
  
• CERCLA—Comprehensive Environmental Response, Compensation, and Liability Act "Superfund" (US)
• CERCLIS—Comprehensive Environmental Response, Compensation, and Liability  Information System (US)
• CERTS—Consortium for Electric Reliability Technology Solutions sposored by the United States Department of Energy
  United States Department of Energy
  The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
  
   and California Energy Commission
  California Energy Commission
  The California Energy Commission is California’s primary energy policy and planning agency. Created in 1974 and headquartered in Sacramento, the Commission has responsibility for activities that include forecasting future energy needs, promoting energy efficiency through appliance and building...
  
   (US)
• CfD—Contract for difference
  Contract for difference
  In finance, a contract for difference is a contract between two parties, typically described as "buyer" and "seller", stipulating that the buyer will pay to the seller the difference between the current value of an asset and its value at contract time...
  
  
• CFS—cubic feet per second
• CFTC—Commodity Futures Trading Commission
  Commodity Futures Trading Commission
  The U.S. Commodity Futures Trading Commission is an independent agency of the United States government that regulates futures and option markets....
  
  
• CH₄—Methane
  Methane
  Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
  
  
• CHP—Combined heat and power
  Combined Heat and Power
  Combined Heat and Power may refer to:* Cogeneration* Combined Heat and Power Solar...
  
  
• CIAC—Contributions in Aid of Construction
• CIP—Critical Infrastructure Protection
  Critical Infrastructure Protection
  Critical infrastructure protection is a concept that relates to the preparedness and response to serious incidents that involve the critical infrastructure of a region or nation....
  
   (US)
• —see also EPCIP European Programme for Critical Infrastructure Protection
  European Programme for Critical Infrastructure Protection
  The European Programme for Critical Infrastructure Protection refers to the doctrine and programmes created to identify and protect critical infrastructure that, in case of fault, incident or attack, could seriously impact both the country where it is hosted and at least one other European Member...
  
  
• CCIP—Centre for Critical Infrastructure Protection
  Centre for Critical Infrastructure Protection
  The Centre for Critical Infrastructure Protection is an organisational unit of New Zealand's Government Communications Security Bureau...
  
   (New Zealand)
• CMVE—Competitive Market Value Estimate
• CNG—Compressed natural gas
  Compressed natural gas
  Compressed natural gas is a fossil fuel substitute for gasoline , diesel, or propane/LPG. Although its combustion does produce greenhouse gases, it is a more environmentally clean alternative to those fuels, and it is much safer than other fuels in the event of a spill...
  
  
• CO—Carbon monoxide
  Carbon monoxide
  Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...
  
  
• CO₂—Carbon dioxide
  Carbon dioxide
  Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
  
  
• COC—Cost of capital
  Cost of capital
  The cost of capital is a term used in the field of financial investment to refer to the cost of a company's funds , or, from an investor's point of view "the shareholder's required return on a portfolio of all the company's existing securities"...
  
  
• COE—U.S. Army Corps of Engineers
• CP—Coincident Peak
  • —Certificate Proceeding
• CPA—California Power Authority
• CPI—Consumer Price Index
  Consumer price index
  A consumer price index measures changes in the price level of consumer goods and services purchased by households. The CPI, in the United States is defined by the Bureau of Labor Statistics as "a measure of the average change over time in the prices paid by urban consumers for a market basket of...
  
  
• CPP—Critical Peak Pricing
• CPP-F—Critical peak fixed
• CPP-F—Critical peak variable
• CPS—Control Performance Standard
  • —Cycles per second (hertz)
• CPUC—California Public Utilities Commission
  California Public Utilities Commission
  The California Public Utilities Commission is a regulatory agency which regulates privately owned public utilities in the state of California, including electric power, telecommunications, natural gas and water companies...
  
  
• CREF—Caribbean Renewable Energy Facility
• CRP—Conservation Reserve Program
  Conservation Reserve Program
  The Conservation Reserve Program is a cost-share and rental payment program under the United States Department of Agriculture , and is administered by the USDA Farm Service Agency . Technical assistance for CRP is provided by the USDA Forest Service and the USDA Natural Resources Conservation...
  
   (US)
• CRT—Capacity Reservation Tariff
• CSD—Commission for Sustainable Development (UN)
• CSEM—Center for the Study of Energy Markets (US)
• CSP—Country Strategy Paper
  • —Curtailment service provider
• CT—Combustion turbine (electricity)
• CZMA—Coastal Zone Management Act
  Coastal Zone Management Act
  The Coastal Zone Management Act of 1972 is an Act of Congress passed in 1972 to encourage coastal states to develop and implement coastal zone management plans...
  
  

D

• DADRP—Day Ahead Demand Response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   Program
• DANIDA—Danish International Development Agency
• DA-RTP—RTP Day ahead real time pricing (regarding Electricity meter
  Electricity meter
  An electricity meter or energy meter is a device that measures the amount of electric energy consumed by a residence, business, or an electrically powered device....
  
  ing)
• DC—Direct current
  Direct current
  Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
  
  
• DCLM—Direct control load management
  Load management
  Load management is the process of balancing the supply of electricity on the network with the electrical load by adjusting or controlling the load rather than the power station output...
  
  
• DCS—Disturbance Control Standard
• DEFG—Distributed Energy Financial Group (US)
• DEIS—Draft Environmental Impact Statement
  Environmental impact statement
  An environmental impact statement , under United States environmental law, is a document required by the National Environmental Policy Act for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making...
  
   (US)
• DF—Distribution Factor
• DG—Distributed generation
  Distributed generation
  Distributed generation, also called on-site generation, dispersed generation, embedded generation, decentralized generation, decentralized energy or distributed energy, generates electricity from many small energy sources....
  
   (electricity)
  • —Directorate-General
    Directorate-General
    A Directorate-General is a branch of an administration dedicated to a specific field of expertise.* The European Commission: Commission Directorates-General are each headed by a European Commissioner;* The European Patent Office: EPO Directorates-General;...
    
      (EU) (government)
• DIIS—Danish Institute for International Studies (organization)
• DLC—Direct load control (regarding Load management
  Load management
  Load management is the process of balancing the supply of electricity on the network with the electrical load by adjusting or controlling the load rather than the power station output...
  
  )
• DME—Disturbance Monitoring Equipment
• DO—Dissolved oxygen
• DOE—United States Department of Energy
  United States Department of Energy
  The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
  
   (government)
• DOE/FE—United States Department of Energy
  United States Department of Energy
  The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
  
    Office of Fossil Energy (government)
• DOI—United States Department of the Interior
  United States Department of the Interior
  The United States Department of the Interior is the United States federal executive department of the U.S. government responsible for the management and conservation of most federal land and natural resources, and the administration of programs relating to Native Americans, Alaska Natives, Native...
  
   (government)
• DOT—United States Department of Transportation
  United States Department of Transportation
  The United States Department of Transportation is a federal Cabinet department of the United States government concerned with transportation. It was established by an act of Congress on October 15, 1966, and began operation on April 1, 1967...
  
   (government)
• DR—Demand response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
  
• DRAM—Demand Response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   and Advanced Metering Coalition
• DRB—Demonstrated reserve base
• DRCC—Demand Response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   Coordinating Council (coalition)
• DRR—Demand Response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   resources
• DRRC—Demand Response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   Research Center (California)
• DSM—Demand side management
• DSO—Distribution system operator (regarding electricity distribution
  Electricity distribution
  File:Electricity grid simple- North America.svg|thumb|380px|right|Simplified diagram of AC electricity distribution from generation stations to consumers...
  
  
• Dth—Dekatherm (defined as British thermal unit
  British thermal unit
  The British thermal unit is a traditional unit of energy equal to about 1055 joules. It is approximately the amount of energy needed to heat of water, which is exactly one tenth of a UK gallon or about 0.1198 US gallons, from 39°F to 40°F...
  
  s, also written "MMBtu") (measurement)
• DTW—dealer tank wagon (as in, "oil companies setting regional dealer tank wagon pricing") (Oil)

E

• E&D—Exploration and development expenses
• E85—E85 fuel
  E85
  E85 is an abbreviation for an ethanol fuel blend of up to 85% denatured ethanol fuel and gasoline or other hydrocarbon by volume. E85 is commonly used by flex-fuel vehicles in the US, Canada, and Europe. Some of the benefits of E85 over conventional gasoline powered vehicles include the potential...
  
  : A fuel containing a mixture of 85 percent ethanol and 15 percent gasoline
• E95—like E85 fuel
  E85
  E85 is an abbreviation for an ethanol fuel blend of up to 85% denatured ethanol fuel and gasoline or other hydrocarbon by volume. E85 is commonly used by flex-fuel vehicles in the US, Canada, and Europe. Some of the benefits of E85 over conventional gasoline powered vehicles include the potential...
  
   but with less gasoline. A fuel containing a mixture of 95 percent ethanol and 5 percent gasoline
• EA—Environmental assessment as in an Environmental impact assessment
  Environmental impact assessment
  An environmental impact assessment is an assessment of the possible positive or negative impact that a proposed project may have on the environment, together consisting of the natural, social and economic aspects....
  
  
• EAR—Estimated additional resources, as in Considering reserves of uranium deposits
• EC—European Commission
  European Commission
  The European Commission is the executive body of the European Union. The body is responsible for proposing legislation, implementing decisions, upholding the Union's treaties and the general day-to-day running of the Union....
  
  
• ECAR—East Central Area Reliability Coordination Agreement (US)
• EPCIP—European Programme for Critical Infrastructure Protection
  European Programme for Critical Infrastructure Protection
  The European Programme for Critical Infrastructure Protection refers to the doctrine and programmes created to identify and protect critical infrastructure that, in case of fault, incident or attack, could seriously impact both the country where it is hosted and at least one other European Member...
  
  
• ECPA—Electric Consumers Protection Act (US)
• EdF—Electricité de France
  Électricité de France
  Électricité de France S.A. is the second largest French utility company. Headquartered in Paris, France, with €65.2 billion in revenues in 2010, EDF operates a diverse portfolio of 120,000+ megawatts of generation capacity in Europe, Latin America, Asia, the Middle East and Africa.EDF is one of...
  
  
• EDRP—Emergency demand response
  Demand response
  In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
  
   program
• EE—Energy efficiency
  Energy conversion efficiency
  Energy conversion efficiency is the ratio between the useful output of an energy conversion machine and the input, in energy terms. The useful output may be electric power, mechanical work, or heat.-Overview:...
  
  
• EEI—Edison Electric Institute
  Edison Electric Institute
  The Edison Electric Institute is the association of United States shareholder-owned electric power companies. Its members serve 95 percent of the ultimate customers in the shareholder-owned segment of the industry, and represent approximately 70 percent of the U.S. electric power industry...
  
  
• EHV—Extra high voltage
• EIA—Energy Information Administration
  Energy Information Administration
  The U.S. Energy Information Administration is the statistical and analytical agency within the U.S. Department of Energy. EIA collects, analyzes, and disseminates independent and impartial energy information to promote sound policymaking, efficient markets, and public understanding of energy and...
  
   (US)
  • —Environmental impact assessment
    Environmental impact assessment
    An environmental impact assessment is an assessment of the possible positive or negative impact that a proposed project may have on the environment, together consisting of the natural, social and economic aspects....
    
     (international)
• EIB—European Investment Bank
  European Investment Bank
  The European Investment Bank is the European Union's long-term lending institution established in 1958 under the Treaty of Rome. A policy-driven bank, the EIB supports the EU’s priority objectives, especially European integration and the development of economically weak regions...
  
  
• EIPP—Eastern Interconnection
  Eastern Interconnection
  The Eastern Interconnection is one of the two major alternating current power grids in North America. The other major interconnection is the Western Interconnection...
  
   Phasor Project
• EIS—Environmental Impact Statement
  Environmental impact statement
  An environmental impact statement , under United States environmental law, is a document required by the National Environmental Policy Act for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making...
  
   (US)
• ELCON—Electricity Consumers Resources Council
• EMF—Electro magnetic field
• EMP—Environmental Management Plan
• EOR—Enhanced oil recovery
  Enhanced oil recovery
  Enhanced Oil Recovery is a generic term for techniques for increasing the amount of crude oil that can be extracted from an oil field...
  
  
• EPA—United States Environmental Protection Agency
  United States Environmental Protection Agency
  The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
  
  
• EPAct—Energy Policy Act of 1992
  Energy Policy Act of 1992
  The Energy Policy Act is a United States government act.It was passed by Congress and addressed energy efficiency, energy conservation and energy management , natural gas imports and exports , alternative fuels and requiring certain fleets to acquire alternative fuel vehicles, which are capable of...
  
   (US)
  • —Energy Policy Act of 2005
    Energy Policy Act of 2005
    The Energy Policy Act of 2005 is a bill passed by the United States Congress on July 29, 2005, and signed into law by President George W. Bush on August 8, 2005, at Sandia National Laboratories in Albuquerque, New Mexico...
    
     (US)
• EPRI—Electric Power Research Institute
  Electric Power Research Institute
  The Electric Power Research Institute conducts research on issues related to the electric power industry in USA. EPRI is a nonprofit organization funded by the electric utility industry. EPRI is primarily a US based organization, receives international participation...
  
   (US)
• EQR—Electric Quarterly Report
• ERA—Economic Regulatory Administration (part of United States Department of Energy
  United States Department of Energy
  The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
  
  
• ERCOT—Electric Reliability Council of Texas, Inc, a Regional Transmission Organization
  Regional Transmission Organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
  . (US)
• ERGEG—European Regulators Group for Electricity and Gas
• ERO—Electric Reliability Organization. The US designated NERC as its ERO.
• ERRA - Energy Regulators Regional Association
  Energy Regulators Regional Association
  The Energy Regulators Regional Association is a voluntary organization of independent energy regulatory bodies primarily from the Central European and Eurasian regions, with affiliates from Africa, Asia and the Middle East and the United States....
  
  
• ESCO—Energy service company
• ESI—Environmental Sustainability Index
  Environmental Sustainability Index
  The Environmental Sustainability Index ' was a composite index published from 1999 to 2005 that tracked 21 elements of environmental sustainability covering natural resource endowments, past and present pollution levels, environmental management efforts, contributions to protection of the global...
  
  
• ESMAP—Energy Sector Management Assistance Programme
• ESS—Energy Storage System, as in grid energy storage
  Grid energy storage
  Grid energy storage refers to the methods used to store electricity on a large scale within an electrical power grid. Electrical energy is stored during times when production exceeds consumption and the stores are used at times when consumption exceeds production...
  
   (electricity)
• ETBE—ethyl tertiary butyl ether
• ETSO—European Transmission System Operator
  Transmission system operator
  File:Electricity grid simple- North America.svg|thumb|380px|right|Simplified diagram of AC electricity distribution from generation stations to consumersrect 2 243 235 438 Power stationrect 276 317 412 556 Transformer...
  
  s association
• EU—European Union
  European Union
  The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
  
  
• EUEF—European Union Energy Facility
• EUEI—European Union Energy Initiative

F

• FAC—Fuel Adjustment Clause
• FACTS—Flexible Alternating Current Transmission System
• FASB—Financial Accounting Standards Board
  Financial Accounting Standards Board
  The Financial Accounting Standards Board is a private, not-for-profit organization whose primary purpose is to develop generally accepted accounting principles within the United States in the public's interest...
  
  
• FBR—fast breeder reactor
• FCITC—First Contingency Incremental Transfer Capability
• FEIS—Final Environmental impact statement
  Environmental impact statement
  An environmental impact statement , under United States environmental law, is a document required by the National Environmental Policy Act for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making...
  
   (US)
• FELCC—Firm Energy Load Carrying Capability
• FERC—Federal Energy Regulatory Commission
  Federal Energy Regulatory Commission
  The Federal Energy Regulatory Commission is the United States federal agency with jurisdiction over interstate electricity sales, wholesale electric rates, hydroelectric licensing, natural gas pricing, and oil pipeline rates...
  
   (U.S.)
• FGD—Flue gas desulfurization
  Flue gas desulfurization
  Sulfur dioxide is one of the elements forming acid rain. Tall flue-gas stacks disperse emissions by diluting the pollutants in ambient air and transporting them to other regions....
  
  
• FINESSE—Financing Energy Services for Small Scale Users
• Fishway—Fish ladder
  Fish ladder
  A fish ladder, also known as a fishway, fish pass or fish steps, is a structure on or around artificial barriers to facilitate diadromous fishes' natural migration. Most fishways enable fish to pass around the barriers by swimming and leaping up a series of relatively low steps into the waters on...
  
  
• FLPMA—Federal Land Policy and Management Act
  Federal Land Policy and Management Act
  Federal Land Policy Management Act, or FLPMA , is a United States federal law that governs the way in which the public lands administered by the Bureau of Land Management are managed. The law was enacted in 1976 by the 94th Congress. Congress recognized the value of the public lands, declaring...
  
   (US)
• FME—Free market economics
• FONSI—Finding of no significant impact. See Environmental impact statement
  Environmental impact statement
  An environmental impact statement , under United States environmental law, is a document required by the National Environmental Policy Act for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making...
  
   (US)
• FPA—Federal Power Act
  Federal Power Act
  The Federal Power Act is a law appearing in Chapter 12 of Title 16 of the United States Code, entitled "Federal Regulation and Development of Power". Enacted as the Federal Water Power Act on June 10, 1920, and amended many times since, its original purpose was to more effectively coordinate the...
  
   (US)
• FPC—Federal Power Commission
  Federal Power Commission
  The Federal Power Commission was an independent commission of the United States government, originally organized on June 23, 1930, with five members nominated by the president and confirmed by the Senate...
  
   (US)
• FPS—Firm peaking service. See Peaking power plant
  Peaking power plant
  Peaking power plants, also known as peaker plants, and occasionally just "peakers," are power plants that generally run only when there is a high demand, known as peak demand, for electricity.-Peak hours:...
  
  
• FRCC—Florida Reliability Coordinating Council
  Florida Reliability Coordinating Council
  The Florida Reliability Coordinating Council is one of 8 Regional Entities delegated authority to insure reliability by North American Electric Reliability Corporation in North American and was formed on September 16, 1996. The area served by FRCC was previously served by SERC Reliability...
  
   (US)
• FRS—Financial Reporting System
• FT—Firm Transportation Service
• FTC—Federal Trade Commission
  Federal Trade Commission
  The Federal Trade Commission is an independent agency of the United States government, established in 1914 by the Federal Trade Commission Act...
  
   (US)
• FTR—Firm Transmission Rights
• FTS—Firm transportation service
• FUA—The Fuel Use Act (US)
• FUCO—Foreign Utility Company
• FWPA—Federal Water Power Act (US)

G

• G&T—Generation
  Electricity generation
  Electricity generation is the process of generating electric energy from other forms of energy.The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday...
  
   and transmission
  Electric power transmission
  Electric-power transmission is the bulk transfer of electrical energy, from generating power plants to Electrical substations located near demand centers...
  
   utility cooperative
  Utility cooperative
  A utility cooperative is a type of cooperative that is tasked with the delivery of a public utility such as electricity, water or telecommunications to its members...
  
   (electricity)
• GAL—gallon
  Gallon
  The gallon is a measure of volume. Historically it has had many different definitions, but there are three definitions in current use: the imperial gallon which is used in the United Kingdom and semi-officially within Canada, the United States liquid gallon and the lesser used United States dry...
  
   (measurement)
• GAO—Government Accountability Office
  Government Accountability Office
  The Government Accountability Office is the audit, evaluation, and investigative arm of the United States Congress. It is located in the legislative branch of the United States government.-History:...
  
   (General Accounting Office) (US) (government)
• GATT—General Agreement on Tariffs and Trade
  General Agreement on Tariffs and Trade
  The General Agreement on Tariffs and Trade was negotiated during the UN Conference on Trade and Employment and was the outcome of the failure of negotiating governments to create the International Trade Organization . GATT was signed in 1947 and lasted until 1993, when it was replaced by the World...
  
   (government)
• GDP—gross domestic product
  Gross domestic product
  Gross domestic product refers to the market value of all final goods and services produced within a country in a given period. GDP per capita is often considered an indicator of a country's standard of living....
  
   (economics)
• GEF—Global Environmental Facility (environment)
• Genco—Any company doing electricity generation (US) (electricity)
• GFN—Global Footprint Network
• GFSE—Global Forum on Sustainable Energy (organization)
• GHC—Gross Inland (energy) Consumption (EU) (energy)
• GHG—Greenhouse gas
  Greenhouse gas
  A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in the Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone...
  
   (climate)
• GIC—Gas Inventory Charge (natural gas)
• GISB—Gas Industry Standards Board (now NAESB) (US) (natural gas)
• GLDF—Generator to Load Distribution Factor. See Load balancing
  Load balancing (electrical power)
  Load balancing refers to the use of various techniques by electrical power stations to store excess electrical power during low demand periods for release as demand rises....
  
   (electricity)
• Gm³—Billion cubic metre
  Cubic metre
  The cubic metre is the SI derived unit of volume. It is the volume of a cube with edges one metre in length. An alternative name, which allowed a different usage with metric prefixes, was the stère...
  
  s (measurement – gas)
• GMO—Genetically modified organism
  Genetically modified organism
  A genetically modified organism or genetically engineered organism is an organism whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one...
  
  
• GMP—Green Mountain Power (US) (electricity)
• GNP—gross national product (economics)
• GNSED— Global Network for Sustainable Energy Development
• GRI—Gas Research Institute (US) (natural gas)
• GridCo—Any company running a transmission grid (electricity)
  Grid (electricity)
  An electrical grid is a vast, interconnected network for delivering electricity from suppliers to consumers. It consists of three main components: 1) generating plants that produce electricity from combustible fuels or non-combustible fuels ; 2) transmission lines that carry electricity from power...
  
  . Also known as a TransCo (US) (electricity)
• GSF—Generator to Load Distribution Factor. See Load balancing
  Load balancing (electrical power)
  Load balancing refers to the use of various techniques by electrical power stations to store excess electrical power during low demand periods for release as demand rises....
  
   (electricity)
• GSR—Gas Supply Realignment (natural gas)
• Gt—Gigaton  (1 billion tons) (measurement)
• GTCC—Gas Turbine Combined Cycle (electricity)
• GTI—Gas Technology Institute
  Gas Technology Institute
  The Gas Technology Institute is an American non-profit research and development organization which develops, demonstrates, and licenses new energy technologies for private and public clients, with a particular focus on the natural gas industry. GTI is located in Des Plaines, Illinois.-History:The...
  
   (US)
• Gtoe—One billion tons of oil equivalent
  Ton of oil equivalent
  The tonne of oil equivalent is a unit of energy: the amount of energy released by burning one tonne of crude oil, approximately 42 GJ .The toe is sometimes used for large...
  
  (EU) (measurement- oil)
• GVEP—Global Village Energy Partnership (organization)
• GVW—gross vehicle weight (transportation)
• GW—Gigawatt  (one billion watts) (measurement- elect)
• GWE—Gigawatt of electric energy (measurement- elect)
• Gwh—Gigawatt hour (one billion watt hours) (measurement- elect)
• GWP—global warming potential
  Global warming potential
  Global-warming potential is a relative measure of how much heat a greenhouse gas traps in the atmosphere. It compares the amount of heat trapped by a certain mass of the gas in question to the amount of heat trapped by a similar mass of carbon dioxide. A GWP is calculated over a specific time...
  
   (climate)

H

• HCA—Host Control Area (electricity)
• HDD—Heating degree day
  Heating degree day
  Heating degree day is a measurement designed to reflect the demand for energy needed to heat a home or business. It is derived from measurements of outside air temperature. The heating requirements for a given structure at a specific location are considered to be directly proportional to the...
  
  s a qualitative index used to reflect the demand for energy to heat a business (conservation)
• HERS—Home energy rating standard (conservation)
• HHI—Hirschman Herfindahl Index (markets)
• HID—high intensity discharge (electricity)
• hp—Horsepower
  Horsepower
  Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...
  
   (measurement)
• HTGR—high temperature gas cooled reactor (nuclear)
• HVAC
  HVAC
  HVAC refers to technology of indoor or automotive environmental comfort. HVAC system design is a major subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer...
  
  —Heating, ventilation
  Ventilation (architecture)
  Ventilating is the process of "changing" or replacing air in any space to provide high indoor air quality...
  
  , and air conditioning
  Air conditioning
  An air conditioner is a home appliance, system, or mechanism designed to dehumidify and extract heat from an area. The cooling is done using a simple refrigeration cycle...
  
   (conservation)
  • —High voltage
    High voltage
    The term high voltage characterizes electrical circuits in which the voltage used is the cause of particular safety concerns and insulation requirements...
    
     alternating current
    Alternating current
    In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
    
     (electricity)
• HVAR—Highly Valued Aquatic Resource
• HVDC—High Voltage Direct Current

I

• I/C—Interruptible /Curtailable (electricity)
• ICAP—Installed Capacity (electricity)
• ICAP-SCR—Installed capacity special case resources (electricity)
• ICE—Internal combustion engine
  Internal combustion engine
  The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
  
   (transportation)
• ICT—Independent Coordinator of Transmission (US) (electricity)
  • —Information and Communication Technology
• IDC—Interchange Distribution Calculator (electricity)
• IEA—International Energy Agency
  International Energy Agency
  The International Energy Agency is a Paris-based autonomous intergovernmental organization established in the framework of the Organisation for Economic Co-operation and Development in 1974 in the wake of the 1973 oil crisis...
  
   (Paris)
• IEM—Internal electricity market (electricity)
• IEEE—Institute of Electrical and Electronics Engineers
  Institute of Electrical and Electronics Engineers
  The Institute of Electrical and Electronics Engineers is a non-profit professional association headquartered in New York City that is dedicated to advancing technological innovation and excellence...
  
  
• IEPE—Institute of Energy Policy and Economics (France)
• IER—Incremental Energy Rate
• IET—International emission trading (policy)
• IGCC—Integrated coal gasification
  Coal gasification
  Coal gasification is the process of producing coal gas, a type of syngas–a mixture of carbon monoxide , hydrogen , carbon dioxide and water vapour –from coal...
  
   combined cycle
• IGIC—Interim gas inventory charge (natural gas)
• IGSC—Interim gas supply charge (natural gas)
• IGT—Institute of Gas Technology (natural gas)
• IHR—Incremental Heat Rate- plant monitoring (electricity)
• IIASA—International Institute for Applied System Analysis
• IJC—International Joint Commission
  International Joint Commission
  The International Joint Commission is an independent binational organization established by the United States and Canada under the Boundary Waters Treaty of 1909.The Commission has responsibilities related to the following treaties and agreements:...
  
  
• ILP—Integrated Licensing Process
• INGAA—Interstate Natural Gas Association of America
• IOS—Interconnected Operations Services (electricity)
• IOU—Investor owned utility (electricity)
• IPAA—Independent Petroleum Association of America (oil)
• IPCC—Intergovernmental Panel on Climate Change
  Intergovernmental Panel on Climate Change
  The Intergovernmental Panel on Climate Change is a scientific intergovernmental body which provides comprehensive assessments of current scientific, technical and socio-economic information worldwide about the risk of climate change caused by human activity, its potential environmental and...
  
   (climate)
• IPP—Independent Power Producer
  Independent Power Producer
  An Independent Power Producer is an entity, which is not a public utility, but which owns facilities to generate electric power for sale to utilities and end users...
  
   (electricity)
• IPS/UPS—Integrated Power System/United Power System
  IPS/UPS
  The IPS/UPS is a wide area synchronous transmission grid of some CIS countries with a common mode of operation and centralized supervisory control. It has an installed generation capacity of 300 gigawatts, and produces 1,200 terawatt-hours per year for its 280 million customers...
  
  , consisting of Independent Power Systems of 12 countries bordering Russia and the Unified Power System of Russia
• IROL—Interconnection Reliability Operating Limit (electricity)
• IRP—Integrated Resource Planning
• IRR—Internal Rate of Return
  Internal rate of return
  The internal rate of return is a rate of return used in capital budgeting to measure and compare the profitability of investments. It is also called the discounted cash flow rate of return or the rate of return . In the context of savings and loans the IRR is also called the effective interest rate...
  
   (finance)
• ISO—Independent System Operator (US) (see also TSO
  Transmission system operator
  File:Electricity grid simple- North America.svg|thumb|380px|right|Simplified diagram of AC electricity distribution from generation stations to consumersrect 2 243 235 438 Power stationrect 276 317 412 556 Transformer...
  
  ) Responsible for grid management, but does not own assets. (electricity)
• ISO-NE—Independent System Operator of New England
  ISO New England
  ISO New England Inc. is an independent, non-profit Regional Transmission Organization , serving Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island and Vermont....
  
  , a Regional Transmission Organization
  Regional Transmission Organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
  . (US) (electricity)
• ISO—NE ISO New England, Inc. (electricity)
• ISS—Interruptible Sales Service
• IT—Interruptible Transportation is gas shipment via pipeline whose delivery may be interrupted in favor of "firm shipment" contracts if there is lack of capacity. (natural gas)
• ITC—Investment tax credit (policy)
• ITS—"Interruptible Transportation Service" is gas shipment via pipeline whose delivery may be interrupted in favor of "firm shipment" contracts if there is lack of capacity. (natural gas)

K

• koe—One kilogram oil equivalent
  Kilogram oil equivalent
  Kilogram of oil equivalent is a normalised unit of energy. By convention it is equivalent to the approximate amount of energy that can be extracted from one kilogram of crude oil...
  
   (EU) (measurement)
• kV—Kilovolt  (one thousand volts) (measurement)
• KVA—One thousand volt Ampere (measurement)
• kvar—one thousand vars (measurement)
• Kw—Kilowatt (one thousand watts) (measurement)
• KWE—kilowatt electric (measurement)
• kWh—Kilowatt hour (one thousand watt hours) (measurement)

L

• LaaR—Load acting as a resource (ERCOT category) (electricity)
• LBNL—Lawrence Berkeley National Laboratory
  Lawrence Berkeley National Laboratory
  The Lawrence Berkeley National Laboratory , is a U.S. Department of Energy national laboratory conducting unclassified scientific research. It is located on the grounds of the University of California, Berkeley, in the Berkeley Hills above the central campus...
  
   (US)
• LDC—Local Distribution Company (electricity)
• LEVP—Low Emissions Vehicle Program
• LHV—lower heating value
• LIHEAP—Low Income Home Energy Assistance Program
• LIPA—Long Island Power Authority
  Long Island Power Authority
  The Long Island Power Authority or LIPA [ "lie-pah" ], a municipal subdivision of the State of New York, was created under the Long Island Power Act of 1985 to acquire the Long Island Lighting Company 's assets and securities...
  
   (US) (electricity)
• LMP—Locational marginal price/pricing. See explanation in electricity markets.
• LNG—Liquified Natural Gas
• LODF—Line Outage Distribution Factor (electricity)
• LOLE—Loss of Load Expectation (electricity)
• LPG—liquefied petroleum gas
• LPN—Lender Participation Notes
• LRG—liquefied refinery gases
• LSE—Load serving entity
• LSF—Load Shift Factor
• lsfo—Low sulfur fuel oil
• LWR—light water reactor
  Light water reactor
  The light water reactor is a type of thermal reactor that uses normal water as its coolant and neutron moderator. Thermal reactors are the most common type of nuclear reactor, and light water reactors are the most common type of thermal reactor...
  
  

M

• MAAC—Mid Atlantic Area Council (US- geographically within PJM)
• MADRI—Mid Atlantic Distributed Resources Initiative (US)
• MAIN—Mid America Interconnected Network (US)
• MAOP—Maximum allowable operating pressure
  Maximum allowable operating pressure
  Maximum allowable operating pressure or MAOP refers to the wall strength of a pressurized cylinder such as a pipeline or storage tank and how much pressure the walls may safely hold in normal operation....
  
  
• MAPP—Mid Continent Area Power Pool (US)
• MBD—million barrels per day
• MBOED—One million barrels of oil equivalent
  Barrel of oil equivalent
  The barrel of oil equivalent is a unit of energy based on the approximate energy released by burning one barrel of crude oil. The US Internal Revenue Service defines it as equal to 5.8 × 106 BTU...
  
  (EU)
• MBR—Market based Rates
• MBS—Macro economic Budget Support
• Mcf—Roman numeral "M" for one thousand cubic feet (measurement of natural gas)
• MDD—Maximum Daily Delivery Obligations
• MDDQ—Maximum Daily Delivery Quantity
• MDM—Meter Data Management
  Meter Data Management
  Meter Data Management refers to a key component in the Smart Grid infrastructure that is in the process of being evolved and adopted by utility companies. An MDM system performs long term data storage and management for the vast quantities of data that are now being delivered by smart metering...
  
  
• MDQ—Maximum Daily Quantities
• MECS—Manufacturing Energy Consumption Survey
• MEDREP—Mediterranean Renewables Energy Partnership
• MER—Maximum efficient rate
• MERC—Mobile Emission Reduction Credit (MERC)
  Mobile Emission Reduction Credit (MERC)
  A mobile emission reduction credit is an emission reduction credit generated within the transportation sector. The term “mobile sources” refers to motor vehicles, engines, and equipment that move, or can be moved, from place to place...
  
   (US)
• MFV—Modified fixed variable rate
• MISO—Midwest Independent Transmission System Operator
  Midwest Independent Transmission System Operator
  The Midwest Independent Transmission System Operator, Inc. is an Independent System Operator and the Regional Transmission Organization that provides open-access transmission service and monitors the high voltage transmission system throughout the Midwest United States and Manitoba, Canada...
  
  , Inc. A Regional Transmission Organization
  Regional Transmission Organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
  . (US)
• MLP—Maximum lawful price
• MLRA—Major Land Resource Areas
  Major Land Resource Areas
  In United States conservation policy, Major Land Resource Areas are geographically associated land resource units delineated by the Natural Resources Conservation Service and characterized by a particular pattern that combines soils, water, climate, vegetation, land use, and type of farming. ...
  
  
• MM—Used to denote million in gas usage
• MMbbl/d—one million barrels of oil per day
• MMBtu—1 million British thermal unit
  British thermal unit
  The British thermal unit is a traditional unit of energy equal to about 1055 joules. It is approximately the amount of energy needed to heat of water, which is exactly one tenth of a UK gallon or about 0.1198 US gallons, from 39°F to 40°F...
  
  s, same as dekatherm
• MMC—Market Monitoring Center
• MMCF—one million cubic feet (measurement of natural gas)
• MMCFD—one million cubic feet per day
• MMGAL—one million gallons
• MMGAL/D—one million gallons per day
• MMS—Mineral Management Service (US)
• MMST—one million short ton
  Short ton
  The short ton is a unit of mass equal to . In the United States it is often called simply ton without distinguishing it from the metric ton or the long ton ; rather, the other two are specifically noted. There are, however, some U.S...
  
  s
• MODFLOW—model of groundwater flow
• MOU—Memorandum of Understanding
  Memorandum of understanding
  A memorandum of understanding is a document describing a bilateral or multilateral agreement between parties. It expresses a convergence of will between the parties, indicating an intended common line of action. It is often used in cases where parties either do not imply a legal commitment or in...
  
  
• MOX—mixed oxide fuel (nuclear)
• MPG—Miles per gallon
• MRO—Midwest Reliability Organization
  Midwest Reliability Organization
  The Midwest Reliability Organization began operations on January 1, 2005, as the successor to the Mid-continent Area Power Pool , which was formed in 1965. MRO is one of nine regional electric reliability councils under North American Electric Reliability Corporation authority...
  
   (US)
• MSA—metropolitan statistical area
• MSHA—Mine Safety and Health Administration
  Mine Safety and Health Administration
  The Mine Safety and Health Administration is an agency of the United States Department of Labor which administers the provisions of the Federal Mine Safety and Health Act of 1977 to enforce compliance with mandatory safety and health standards as a means to eliminate fatal accidents, to reduce...
  
   (US)
• msl—Mean sea level
• MSW—Municipal solid waste
  Municipal solid waste
  Municipal solid waste , commonly known as trash or garbage , refuse or rubbish is a waste type consisting of everyday items we consume and discard. It predominantly includes food wastes, yard wastes, containers and product packaging, and other miscellaneous inorganic wastes from residential,...
  
  
• Mt—one million ton
  Ton
  The ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of weight, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.It is derived from...
  
  s (ambiguous as to whether short tons or metric tons)
  • —one Metric ton
• MTBE—methyl tertiary butyl ether
• MTEF—Medium Term Expenditure Framework
• MTEP—Midwest ISO Transmission Expansion Plan 2005 (US)
• Mtoe—One million tons of oil equivalent
  Ton of oil equivalent
  The tonne of oil equivalent is a unit of energy: the amount of energy released by burning one tonne of crude oil, approximately 42 GJ .The toe is sometimes used for large...
  
  (EU)
• Muni—Municipality
  Municipality
  A municipality is essentially an urban administrative division having corporate status and usually powers of self-government. It can also be used to mean the governing body of a municipality. A municipality is a general-purpose administrative subdivision, as opposed to a special-purpose district...
  
  
• MVA—Megavolt amperes (one million volt amperes)
• MW—Megawatt (one million watts)
• MWE—megawatt electric
• MWh—Megawatt hour (one million watt hours)

N

• N₂O—nitrous oxide
  Nitrous oxide
  Nitrous oxide, commonly known as laughing gas or sweet air, is a chemical compound with the formula . It is an oxide of nitrogen. At room temperature, it is a colorless non-flammable gas, with a slightly sweet odor and taste. It is used in surgery and dentistry for its anesthetic and analgesic...
  
  
• NAAQS—National Ambient Air Quality Standards
  National Ambient Air Quality Standards
  The National Ambient Air Quality Standards are standards established by the United States Environmental Protection Agency under authority of the Clean Air Act that apply for outdoor air throughout the country...
  
   (US)
• NAESB—North American Energy Standards Board (formerly GISB)
• NAFTA—North American Free Trade Agreement
  North American Free Trade Agreement
  The North American Free Trade Agreement or NAFTA is an agreement signed by the governments of Canada, Mexico, and the United States, creating a trilateral trade bloc in North America. The agreement came into force on January 1, 1994. It superseded the Canada – United States Free Trade Agreement...
  
  
• NAICS—North American Industry Classification System
• NAP—National Action Plan
• NARUC—National Association of Regulatory Utility Commissioners (US) http://www.naruc.org
• NAS—United States National Academy of Sciences
  United States National Academy of Sciences
  The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...
  
  
• NASPI—North American Synchrophasor
  Synchrophasor
  A phasor measurement unit is a device which measures the electrical waves on an electricity grid, using a common time source for synchronization. Time synchronization allows synchronized real-time measurements of multiple remote measurement points on the grid...
  
   Initiative
• NASUCA—National Association of Utility Consumer Advocates(US)
• NATC—Non Recallable Available Transfer Capability
• NBS—National Bureau of Standards (US)
• NCD—Non coincidental Demand
• NCEP—National Council on Electricity Policy (US) http://www.ncouncil.org
• NCSL—National Conference of State Legislatures
  National Conference of State Legislatures
  The National Conference of State Legislatures is a bipartisan non-governmental organization established in 1975 to serve the members and staff of state legislatures of the United States...
  
   (US)
• NEA—The National Energy Act
  National Energy Act
  The National Energy Act of 1978 was a legislative response by the U.S. Congress to the 1973 energy crisis. It includes the following statutes:* Public Utility Regulatory Policies Act * Energy Tax Act * National Energy Conservation Policy Act...
  
   of 1978 (US)
• NEB—National Energy Board
  National Energy Board
  The National Energy Board is an independent economic regulatory agency created in 1959 by the Government of Canada to oversee "international and inter-provincial aspects of the oil, gas and electric utility industries"...
  
   (Canada)
• NEDRI—New England Distributed Resources Initiative (US)
• NEPA—National Environmental Policy Act
  National Environmental Policy Act
  The National Environmental Policy Act is a United States environmental law that established a U.S. national policy promoting the enhancement of the environment and also established the President's Council on Environmental Quality ....
  
   (US)
• NEPOOL—New England Power Pool
• NERC—North American Electric Reliability Council
  North American Electric Reliability Council
  The North American Electric Reliability Corporation , a nonprofit corporation based in Atlanta, GA, was formed on March 28, 2006, as the successor to the North American Electric Reliability Council...
  
  
• NGA—Natural Gas Act (US)
• NGAA—Natural Gasoline Association of America (US)
• NGL—natural gas
  Natural gas
  Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
  
   liquids
• NGPA—Natural Gas Policy Act of 1978 (US)
• NGPL—Natural gas
  Natural gas
  Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
  
   plant liquids
• NGPSA—Natural Gas Pipeline Safety Act of 1968 (US)
• NGSA—Natural Gas Supply Association (US)
• NGV—Natural gas vehicle
  Natural gas vehicle
  thumb|right|200px|2009 [[Honda Civic GX]] hooked up to Phill refueling system.A natural gas vehicle or NGV is an alternative fuel vehicle that uses compressed natural gas or liquefied natural gas as a clean alternative to other fossil fuels...
  
  
• NHPA—National Historic Preservation Act (US)
• NIETC—National Interest Electric Transmission Corridor
  National Interest Electric Transmission Corridor
  A National Interest Electric Transmission Corridor corridor is a geographic region designated by the United States Department of Energy where electricity transmission limitations are adversely affecting American citizens...
  
   (US)
• NITC—Normal Incremental Transfer Capability
• NIMBY—Not in my backyard
  NIMBY
  NIMBY or Nimby is an acronym for the phrase "not in my back yard". The term is used pejoratively to describe opposition by residents to a proposal for a new development close to them. Opposing residents themselves are sometimes called Nimbies...
  
   regarding siting of energy generation and transmission infrastructure.
• NOAA—National Oceanic and Atmospheric Administration
  National Oceanic and Atmospheric Administration
  The National Oceanic and Atmospheric Administration , pronounced , like "noah", is a scientific agency within the United States Department of Commerce focused on the conditions of the oceans and the atmosphere...
  
   (US)
• NOI—Notice of Intent or Notice of Inquiry or Notice of Investigation
• NOPR—Notice of Proposed Rulemaking
  Notice of proposed rulemaking
  A notice of proposed rulemaking is a public notice issued by law when one of the independent agencies of the United States government wishes to add, remove, or change a rule or regulation as part of the rulemaking process. It is an important part of United States administrative law which...
  
   (US)
• NORDEL—association of Nordic electric system operators, comprising Denmark, Finland, Norway, Sweden
• NOx—nitrogen oxides
• NPCC—Northeast Power Coordinating Council
  Northeast Power Coordinating Council
  The Northeast Power Coordinating Council was formed January 19, 1966, as a successor to the Canada–United States Eastern Interconnection . NPCC is one of nine regional electric reliability councils under North American Electric Reliability Corporation authority. NERC and the regional...
  
   (US)
• NPV—Net Present Value
  Net present value
  In finance, the net present value or net present worth of a time series of cash flows, both incoming and outgoing, is defined as the sum of the present values of the individual cash flows of the same entity...
  
  
• NRC—Nuclear Regulatory Commission
  Nuclear Regulatory Commission
  The Nuclear Regulatory Commission is an independent agency of the United States government that was established by the Energy Reorganization Act of 1974 from the United States Atomic Energy Commission, and was first opened January 19, 1975...
  
   (US)
• NRCS—National Resource Conservation Service (US)
• NRECA—National Association of Rural Electric Cooperatives (US)
• NREPA—National Resource and Environmental Protection Act (US)
• NRI—National Rivers Inventory (US)
• NSA—Noise sensitive area
• NTAC—Northwest Transmission Assessment Committee (US)
• NUG—Non Utility Generator
• NURE—national uranium resource evaluation (US)
• NYDER—New York Department of Environmental Resources
• NYISO—New York Independent System Operator, Inc. (US)
• NYMEX—New York Mercantile Exchange
  New York Mercantile Exchange
  The New York Mercantile Exchange is the world's largest physical commodity futures exchange. It is located at One North End Avenue in the World Financial Center in the Battery Park City section of Manhattan, New York City...
  
  
• NYPSC—New York Public Service Commission
  New York Public Service Commission
  The New York Public Service Commission is a government agency that regulates the various utilities of the state of New York. The commission also oversees the cable industry.The commission consists of up to five members, led by a commissioner...
  
  
• NYSERDA—New York State Energy Research and Development Authority

O

• O&M—Operation and Maintenance Expenses
• O₃—Ozone
  Ozone
  Ozone , or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope...
  
  
• OASIS—Open Access Same-Time Information System
  Open Access Same-Time Information System
  The Open Access Same-Time Information System , is an Internet-based system for obtaining services related to electric power transmission in North America. It is the primary means by which high-voltage transmission lines are reserved for moving wholesale quantities of electricity...
  
  
• OATT—Open Access Transmission Tariff (US)
• OCS—Outer Continental Shelf
  Outer Continental Shelf
  The Outer Continental Shelf is a peculiarity of the political geography of the United States and is the part of the internationally recognized continental shelf of the United States which does not fall under the jurisdictions of the individual U.S...
  
   (oil)
• OCSLA—Outer Continental Shelf Lands Act (oil)
• OECD—Organization for Economic Cooperation and Development
• OEM—original equipment manufacturers
• OFO—Operational Flow Order
• OMP—Operation and Maintenance Plan
• Ontario—IESO Ontario Independent Electricity System Operator (Canada)
• OPEC—Organization of Petroleum-Exporting Countries (oil)
• OPRG—oxygenated fuels program reformulated gasoline (oil)
• ORNL—Oak Ridge National Laboratory (U.S.) (nuclear)
• OSHA—U.S. Department of Labor Occupational Safety and Health Administration
• OTAG—Ozone Transport Assessment Group
• OTDF—Outage Transfer Distribution Factor
• OTEC—ocean thermal energy conversion
  Ocean thermal energy conversion
  Ocean Thermal Energy Conversion uses the difference between cooler deep and warmer shallow or surface ocean waters to run a heat engine and produce useful work, usually in the form of electricity....
  
   (electricity)

P

• PA—Planning Authority
  • —Programmatic Agreement
• PADD—Petroleum Administration for Defense Districts (US)
• PBR—pebble bed reactor
  Pebble bed reactor
  The pebble bed reactor is a graphite-moderated, gas-cooled, nuclear reactor. It is a type of very high temperature reactor , one of the six classes of nuclear reactors in the Generation IV initiative...
  
   (nuclear)
  • —performance based rates (electricity)
  • —Performance Based Regulation
• PCB—polychlorinated biphenyl
  Polychlorinated biphenyl
  Polychlorinated biphenyls are a class of organic compounds with 2 to 10 chlorine atoms attached to biphenyl, which is a molecule composed of two benzene rings. The chemical formula for PCBs is C12H10-xClx...
  
  
• PCM—Project Cycle Management
• PCT—Programmable Communicating Thermostat
  Programmable Communicating Thermostat
  The term programmable communicating thermostat is used by the California Energy Commission to describe programmable thermostats that can receive information wirelessly....
  
   (electricity)
• PD—Preliminary Determination
• PDC—Phasor data concentrator. See description in phasor measurement unit article. (electricity)
• PDCI—Pacific Direct Current Intertie (US) (electricity)
• PEM—Proton Exchange Membrane
  Proton exchange membrane
  A proton exchange membrane or polymer electrolyte membrane is a semipermeable membrane generally made from ionomers and designed to conduct protons while being impermeable to gases such as oxygen or hydrogen...
  
  
• PFC—perfluorocarbons
• PG&E—Pacific Gas & Electric (US) (electricity)
• PGA—Purchased gas adjustment
• PHA—Production Handling Agreement
• PHFFU—Plant held for future use
• PIDX—Petroleum Industry Data Exchange (oil)
• PIER—Public Interest Energy Research (CEC)
• PIFUA—Powerplant and Industrial Fuel Use Act of 1978
• PJM—PJM Interconnection
  PJM Interconnection
  PJM Interconnection LLC is a Regional Transmission Organization which is part of the Eastern Interconnection grid operating an electric transmission system serving all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee,...
  
  , LLC, a Regional Transmission Organization
  Regional Transmission Organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
  . (US) (electricity)
• PLC—Power line communication
  Power line communication
  Power line communication or power line carrier , also known as power line digital subscriber line , mains communication, power line telecom , power line networking , or broadband over power lines are systems for carrying data on a conductor also used for electric power transmission.A wide range...
  
   (electricity)
• PLMA—Peak Load Management Association (US) (electricity)
• PM—Particulate matter
• PM&E—Protection, mitigation and enhancement
• PMA—Power Marketing Administration or Fed. Power Marketing Agency (US) (electricity)
• PMU—Phasor measurement unit (electricity)
• PNNL—Pacific Northwest National Laboratory (DOE) (US)
• POD—Point of Delivery
  Point of Delivery
  A point of delivery, or POD, is "a module of network, compute, storage, and application components that work together to deliver networking services. The POD is a repeatable pattern, and its components maximize the modularity, scalability, and manageability of data centers." The concept of a design...
  
  
• POLES—Prospective On Long Term Energy Systems
• POLR—Provider of last resort (electricity)
• PPA—Power Purchase Agreement
  Power Purchase Agreement
  Power Purchase Agreements are contracts between two parties, one who generates electricity for the purpose of sale and one who is looking to purchase electricity . There are various forms of Power Purchase Agreements; these are differentiated by the source of energy harnessed...
  
   (electricity)
• PPI—producer price index
  Producer price index
  A Producer Price Index measures average changes in prices received by domestic producers for their output. It is one of several price indices.Its importance is being undermined by the steady decline in manufactured goods as a share of spending....
  
  
• ppmv—Parts Per Million by Volume
• ppp—Purchasing power parity
  Purchasing power parity
  In economics, purchasing power parity is a condition between countries where an amount of money has the same purchasing power in different countries. The prices of the goods between the countries would only reflect the exchange rates...
  
  
• PPR—Potential peak reduction
• PREP—Pacific Regional Energy Programme
• PRESSEA—Promotion of Renewable Energy Sources in South East Asia (PRESSEA)
• Prim—Primary (electricity) nuclear, hydro, geothermal, wind, solar
• PSC—Public Service Commission
  Public Utilities Commission
  A Utilities commission, Utility Regulatory Commission , Public Utilities Commission or Public Service Commission is a governing body that regulates the rates and services of a public utility...
  
  
• PSD—Prevention of Significant Deterioration
• PSE—Puget Sound Energy
  Puget Sound Energy
  Puget Sound Energy is Washington state's oldest local energy utility providing electrical power and natural gas in the Puget Sound region of the northwest United States...
  
   (US) (electricity)
• PTDF—Power Transfer Distribution Factor (electricity)
• PTP—Point to Point Transmission Service (electricity)
• PUC—Public Utility Commission (electricity)
• PUD—Public Utility District
  Public utility district
  In the United States, a public utility district is a special-purpose district or other governmental jurisdiction that provides public utilities to the residents of that district.PUDs are created by a local government body, such as a city, county, or...
  
   (electricity)
• PUHCA—Public Utility Holding Company Act of 1935
  Public Utility Holding Company Act of 1935
  The Public Utility Holding Company Act of 1935 , , also known as the Wheeler-Rayburn Act, was a law that was passed by the United States Congress to facilitate regulation of electric utilities, by either limiting their operations to a single state, and thus subjecting them to effective state...
  
   (US) (electricity)
• PURPA—Public Utility Regulatory Policies Act of 1978 (US) (electricity)
• PV—photovoltaic (solar)
• PVC—photovoltaic cell (solar)
• PVC—polyvinyl chloride
  Polyvinyl chloride
  Polyvinyl chloride, commonly abbreviated PVC, is a thermoplastic polymer. It is a vinyl polymer constructed of repeating vinyl groups having one hydrogen replaced by chloride. Polyvinyl chloride is the third most widely produced plastic, after polyethylene and polypropylene. PVC is widely used in...
  
  
• PWR—pressurized water reactor
  Pressurized water reactor
  Pressurized water reactors constitute a large majority of all western nuclear power plants and are one of three types of light water reactor , the other types being boiling water reactors and supercritical water reactors...
  
   (nuclear)
• PX—Power exchange
  Electricity market
  In economic terms, electricity is a commodity capable of being bought, sold and traded. An electricity market is a system for effecting purchases, through bids to buy; sales, through offers to sell; and short-term trades, generally in the form of financial or obligation swaps. Bids and offers use...
  
  

Q

• QF—qualifying facility
• QSE—Qualifying scheduling entity
• QUAD—10¹⁵ Btu
  British thermal unit
  The British thermal unit is a traditional unit of energy equal to about 1055 joules. It is approximately the amount of energy needed to heat of water, which is exactly one tenth of a UK gallon or about 0.1198 US gallons, from 39°F to 40°F...
  
   (a quadrillion in the short scale)

R

• R/P—Reserve on Production
  • —Reserves to Production
• RAB—Regional Advisory Body (US)
• RAC—Refiners' acquisition cost
• RAP—Regulatory Assistance Project
• RAR—Reasonable assured resources
• RAS—Remedial Action Scheme
• RATC—Recallable Available Transmission Capability
• RBMK—Russian: Реактор Большой Мощности Канальный = "High Power Channel Type Reactor" (RU)
• RBOB—reformulated gasoline blendstock for oxygenate blending
• RC—Reliability Coordinator
• RCIS—Reliability Coordinator Information System
• RCRA—Resource Conservation and Recovery Act
  Resource Conservation and Recovery Act
  The Resource Conservation and Recovery Act , enacted in 1976, is the principal Federal law in the United States governing the disposal of solid waste and hazardous waste.-History and Goals:...
  
   (US)
• RDF—refuse derived fuel (electricity)
• REA—Rural Electrification Administration (US)
• RECS—Residential Energy Consumption Survey (US)
• REEEP—Renewable Energy and Energy Efficiency Partnership
  Renewable Energy and Energy Efficiency Partnership
  The Renewable Energy and Energy Efficiency Partnership is a Vienna-based non-profit organisation that aims to accelerate the marketplace for renewable energy and energy efficiency with a particular emphasis on the emerging markets and developing countries.The organisation funds small-to-medium...
  
  
• RES—Renewable energy source
• RET/EE—IAF Renewable Energy Technology & Energy Efficiency Investment Advisory Facility
• RF—Radio frequency
  Radio frequency
  Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
  
  
• RFA—Regulatory Flexibility Act (US)
• RFC—ReliabilityFirst Corporation (US) (electricity)
• RFG—reformulated gasoline (oil)
• RFI—Request for Interchange
• RFP—Request for proposals
• RM—Rulemaking
  Rulemaking
  In administrative law, rulemaking refers to the process that executive and independent agencies use to create, or promulgate, regulations. In general, legislatures first set broad policy mandates by passing statutes, then agencies create more detailed regulations through rulemaking.By bringing...
  
  
• RMATS—Rocky Mountain Area Transmission Study (US) (electricity)
• RMR—Reliability Must Run (electricity)
• RMU—Removal Units
  Removal Units
  A Removal Unit is a tradable carbon credit or 'Kyoto unit' representing an allowance to emit one metric tonne of greenhouse gases absorbed by a removal or Carbon sink activity in an Annex I country....
  
  
• ROA—Return of Assets (finance)
• ROE—Return of Equity (finance)
• ROFR—Right of First Refusal
  Right of first refusal
  Right of first refusal is a contractual right that gives its holder the option to enter a business transaction with the owner of something, according to specified terms, before the owner is entitled to enter into that transaction with a third party...
  
   (finance)
• ROI—Return on Investment
  Return on investment
  Return on investment is one way of considering profits in relation to capital invested. Return on assets , return on net assets , return on capital and return on invested capital are similar measures with variations on how “investment” is defined.Marketing not only influences net profits but also...
  
  
• ROW—Right of Way
  Right of Way
  Right of Way is a 1983 television film drama starring Bette Davis and James Stewart, and directed by George Schaefer.The TV movie stars film veterans Davis and Stewart as an elderly long-married couple who must decide how to deal with the situation of one of them being diagnosed with a terminal...
  
  
• RPM—Reliability Pricing Model. See explanation in electricity markets#Electricity market experience. (electricity)
• RRO—Regional reliability organization (US)
• RSE—Revenue Stream Estimate (finance)
• RSE—relative standard error
• RTEP—Regional transmission expansion plan
• RTG—Regional Transmission Group (US)
• RTO—Regional transmission organization
  Regional transmission organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
   (US)
• RTP—Real time Pricing
• RTU—Remote Terminal Unit
• RUS—Rural Utilities Service
  Rural Utilities Service
  is an agency of the United States Department of Agriculture , one of the federal executive departments of the United States government charged with providing public utilities to rural areas in the United States via public-private partnerships...
  
  
• RVP—Reid Vapor Pressure
  Reid Vapor Pressure
  Reid vapor pressure is a common measure of the volatility of gasoline. It is defined as theabsolute vapor pressure exerted by a liquid at 100 °F as determined by the test method ASTM-D-323...
  
  

S

• SCADA—Supervisory control and data acquisition a remote control and telemetry system used to monitor and control the electrical system
• SCE—Southern California Edison
  Southern California Edison
  Southern California Edison , the largest subsidiary of Edison International , is the primary electricity supply company for much of Southern California, USA. It provides 14 million people with electricity...
  
   (US)
• scf—Standard cubic foot
  Standard cubic foot
  A standard cubic foot is a measure of quantity of gas, equal to a cubic foot of volume at 60 degrees Fahrenheit and either 14.696 psi or 14.73 psi of pressure.A standard cubic foot is thus not a unit of volume but of quantity, and the conversion to normal cubic metres is...
  
  
• SCO—Stranded Cost Obligation (finance)
• SCR—Special Case Resources (US- NYISO category)
• SDG&E—San Diego Gas & Electric
  San Diego Gas & Electric
  San Diego Gas & Electric is the utility that provides natural gas and electricity to San Diego County and southern Orange County in southwestern California, United States...
  
   (US)
• SEA—Strategic Environmental Assessment
  Strategic Environmental Assessment
  Strategic environmental assessment is a system of incorporating environmental considerations into policies, plans, and programmes. It is sometimes referred to as strategic environmental impact assessment. The specific term strategic environmental assessment relates to European Union policy...
  
  
• SEC—Securities and Exchange Commission (US)
• SEER—seasonal energy efficiency ratio
  Seasonal energy efficiency ratio
  The efficiency of air conditioners is often rated by the Seasonal Energy Efficiency Ratio which is defined by the Air Conditioning, Heating and Refrigeration Institute in its standard ARI 210/240, Performance Rating of Unitary Air-Conditioning and Air-Source Heat Pump Equipment.The SEER rating of...
  
  
• SEFI—Sustainable Energy Finance Initiative
• SEIA—Sustainable Energy Industry Association
• SERC—Southeastern Electric Reliability Council (US)
• SF₆—sulfur hexafluoride
  Sulfur hexafluoride
  Sulfur hexafluoride is an inorganic, colorless, odorless, and non-flammable greenhouse gas. has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. It is a hypervalent molecule. Typical for a nonpolar gas, it is poorly soluble in water but soluble in...
  
  
• SFC—Solid oxide fuel cell  (transportation)
• SFEIS—Supplemental Final Environmental Impact Statement (US)
• SFV—Straight Fixed Variable
• SGR—State game refuge (US)
• SHPO—State Historic Preservation Office (US)
• SI—International System of Units (Système international d'unités)
• SIC—Standard Industrial Classification
  Standard Industrial Classification
  The Standard Industrial Classification is a United States government system for classifying industries by a four-digit code. Established in 1937, it is being supplanted by the six-digit North American Industry Classification System , which was released in 1997; however certain government...
  
  
• SMPs—Special Marketing Programs
• SNG—Synthetic Natural Gas or Substitute Natural Gas
• SO₂—Sulfur dioxide
  Sulfur dioxide
  Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...
  
  
• SOL—System Operating Limit
• SPCC—Spill Prevention, Containment and Countermeasure Plan
  • SPM—Synchronized phasor measurement- a WAMS network with synchrophasor
    Synchrophasor
    A phasor measurement unit is a device which measures the electrical waves on an electricity grid, using a common time source for synchronization. Time synchronization allows synchronized real-time measurements of multiple remote measurement points on the grid...
    
     sensors (PMUs). (electricity)
• SPP—Southwest Power Pool
  Southwest Power Pool
  The Southwest Power Pool is the oldest North American Reliability Organization still in operation. SPP's story began in the early days of WWII, when America was furiously ramping up production of weapons and military supplies. After entering the War, the USA had an immediate and crucial need to...
  
   Inc., a Regional Transmission Organization
  Regional Transmission Organization
  A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
  
   (US)
  • —Statewide Pricing Pilot (US-California)
  • —Small power producer (electricity)
• SPR—Strategic Petroleum Reserve
  Strategic Petroleum Reserve
  The Strategic Petroleum Reserve is an emergency fuel storage of oil maintained by the United States Department of Energy.- United States :The US SPR is the largest emergency supply in the world with the current capacity to hold up to ....
  
   (US)
• SPS—Special Protection System
• SR—Speculative resources For example, regarding uranium deposits. (nuclear)
• SRP—Salt River Agricultural Improvement & Power District (US) (electricity)
• SSG—WI PWG Seams Steering Group of Western Interconnection PlanningWork Group (US) (electricity)
• SSM—Synchronized system measurement-a WAMS with synchronous sensors in addition to PMUs. See Phasor networks.
• STEP—Southwest Transmission Expansion Plan group (US) (electricity)
• SVC—Static VAR compensator
  Static VAr compensator
  A static var compensator is an electrical device for providing fast-acting reactive power on high-voltage electricity transmission networks. SVCs are part of the Flexible AC transmission system device family, regulating voltage and stabilising the system...
  
   (electricity)
• SWAT—Southwest Area Transmission (US) (electricity)
• SWU—Separative work unit

T

• TAME—Tertiary amyl methyl ether
  Tertiary amyl methyl ether
  tert-Amyl methyl ether is an ether used as a fuel oxygenate. It has an ethereous odor. Unlike most ethers, does not form peroxides on storage.-Uses:...
  
  
• TAPS—Trans-Alaska Pipeline System
  Trans-Alaska Pipeline System
  The Trans Alaska Pipeline System , includes the Trans Alaska Pipeline, 11 pump stations, several hundred miles of feeder pipelines, and the Valdez Marine Terminal. TAPS is one of the world's largest pipeline systems...
  
   (natural gas)
• TBA—tertiary butyl alcohol
• TBL—Transmission business line (electricity)
• TBS—Town border station
• Tcf—Trillion cubic feet (measurement)
• TCR—Transition Cost Recovery (Mechanism)
• TDU—Transmission Dependent Utility (electricity)
• TEFRA—Tax Equity and Fiscal Responsibility Act of 1985
• TEN—Trans-European Networks
  Trans-European Networks
  The Trans-European Networks were created by the European Union by Articles 154-156 of the Treaty of Rome , with the stated goals of the creation of an internal market and the reinforcement of economic and social cohesion...
  
   (electricity)
• TLR—Procedures Transmission Line Loading Relief Procedures (electricity)
• TO—Transmission owner (electricity)
• toe—Ton of oil equivalent
  Ton of oil equivalent
  The tonne of oil equivalent is a unit of energy: the amount of energy released by burning one tonne of crude oil, approximately 42 GJ .The toe is sometimes used for large...
  
   (EU)
• TOP—Transmission Operator (electricity)
• TOU—Time of use (rate) (electricity)
• Transco—Transmission Company (US) (electricity)
  • —Transcontinental Pipeline
    Transcontinental Pipeline
    Transcontinental Pipeline is a natural gas pipeline which brings gas from the Gulf coast of Texas, Louisiana, Mississippi, and Alabama, through Georgia, South Carolina, North Carolina, Virginia, Maryland, and Pennsylvania to deliver gas to the New Jersey and New York City area. It is owned by the...
    
     (US) (natural gas)
  • —National Transmission Corporation
    National Transmission Corporation
    The National Transmission Corporation is a Philippine government corporation created in 2001 by the Electric Power Industry Reform Act currently operating the nation's power grid...
    
     (Philippines)
• TRM—Transmission Reliability Margin (electricity)
• TSO—Transmission System Operator
  Transmission system operator
  File:Electricity grid simple- North America.svg|thumb|380px|right|Simplified diagram of AC electricity distribution from generation stations to consumersrect 2 243 235 438 Power stationrect 276 317 412 556 Transformer...
  
  ) (electricity)
• TTC—Total Transfer Capability (electricity)
• TVA—Tennessee Valley Authority
  Tennessee Valley Authority
  The Tennessee Valley Authority is a federally owned corporation in the United States created by congressional charter in May 1933 to provide navigation, flood control, electricity generation, fertilizer manufacturing, and economic development in the Tennessee Valley, a region particularly affected...
  
   (US) (electricity)
• TW—terawatt (one trillion watts) (measurement)
• TWH—terawatt-hour (one trillion watt hours)

U

• U.S.C.—United States Code
  United States Code
  The Code of Laws of the United States of America is a compilation and codification of the general and permanent federal laws of the United States...
  
  
• U₃O₈—triuranium octaoxide
  Triuranium octaoxide
  Triuranium octoxide is a compound of uranium. It is present as an olive green to black, odorless solid. In spite of its color, it is one of the more popular forms of yellowcake and is shipped between mills and refineries in this form....
  
   (nuclear)
• UAE—United Arab Emirates
  United Arab Emirates
  The United Arab Emirates, abbreviated as the UAE, or shortened to "the Emirates", is a state situated in the southeast of the Arabian Peninsula in Western Asia on the Persian Gulf, bordering Oman, and Saudi Arabia, and sharing sea borders with Iraq, Kuwait, Bahrain, Qatar, and Iran.The UAE is a...
  
   (oil)
• UCTE—Union for the Coordination of the Transport of Electricity, the power transmission system of continental Europe
• UF₆—uranium hexaflouride (nuclear)
• UFLS—Under frequency load shedding (electricity)
• UHVAC—Ultra High Voltage Alternating Current (electricity)
• UHVDC—Ultra High Voltage Direct Current (electricity)
• ULCC—Ultra Large Crude Carrier (oil)
• UMTRA—Uranium Mill Tailings Radiation Control Act of 1978 (US)
• UNCCD—United Nations Convention to Combat Desertification
  United Nations Convention to Combat Desertification
  The United Nations Convention to Combat Desertification in Those Countries Experiencing Serious Drought and/or Desertification, Particularly in Africa is a Convention to combat desertification and mitigate the effects of drought through national action programs that incorporate long-term strategies...
  
  
• UNDESA—UN Department of Economic and Social Affairs
• UNDP—United Nations Development Programme
  United Nations Development Programme
  The United Nations Development Programme is the United Nations' global development network. It advocates for change and connects countries to knowledge, experience and resources to help people build a better life. UNDP operates in 177 countries, working with nations on their own solutions to...
  
  
• UNDP—United Nations Development Programme
  United Nations Development Programme
  The United Nations Development Programme is the United Nations' global development network. It advocates for change and connects countries to knowledge, experience and resources to help people build a better life. UNDP operates in 177 countries, working with nations on their own solutions to...
  
  
• UNECE—United Nations Economic Commission for Europe
  United Nations Economic Commission for Europe
  The United Nations Economic Commission for Europe was established in 1947 to encourage economic cooperation among its member states. It is one of five regional commissions under the administrative direction of United Nations headquarters. It has 56 member states, and reports to the UN Economic and...
  
  
• UNEP—United Nations Environment Programme
  United Nations Environment Programme
  The United Nations Environment Programme coordinates United Nations environmental activities, assisting developing countries in implementing environmentally sound policies and practices. It was founded as a result of the United Nations Conference on the Human Environment in June 1972 and has its...
  
  
• UNFCCC—United Nations Framework Convention on Climate Change
• UO₂—uranium dioxide
  Uranium dioxide
  Uranium dioxide or uranium oxide , also known as urania or uranous oxide, is an oxide of uranium, and is a black, radioactive, crystalline powder that naturally occurs in the mineral uraninite. It is used in nuclear fuel rods in nuclear reactors. A mixture of uranium and plutonium dioxides is used...
  
   (nuclear)
• UO₃—uranium trioxide
  Uranium trioxide
  Uranium trioxide , also called uranyl oxide, uranium oxide, and uranic oxide, is the hexavalent oxide of uranium. The solid may be obtained by heating uranyl nitrate to 400 °C. Its most commonly encountered polymorph, γ-UO3, is a yellow-orange powder.-Production and use:There are three methods...
  
   (nuclear)
• UO₄—uranyl peroxide
  Uranyl peroxide
  Uranyl peroxide or uranium peroxide hydrate is a pale-yellow, soluble peroxide of uranium. It is found present at one stage of the enriched uranium fuel cycle and in yellowcake prepared via the in situ leaching and resin ion exchange system. This compound, also expressed as:UO3··, is very similar...
  
   (nuclear)
• UOX—uranium oxide
  Uranium oxide
  Uranium oxide is an oxide of the element uranium.The metal uranium forms several oxides:* Uranium dioxide or uranium oxide * Uranium trioxide or uranium oxide...
  
   (nuclear)
• URR—Ultimate Recoverable Resources
• USBR—United States Bureau of Reclamation
  United States Bureau of Reclamation
  The United States Bureau of Reclamation , and formerly the United States Reclamation Service , is an agency under the U.S...
  
  
• USCE—United States Army Corps of Engineers
  United States Army Corps of Engineers
  The United States Army Corps of Engineers is a federal agency and a major Army command made up of some 38,000 civilian and military personnel, making it the world's largest public engineering, design and construction management agency...
  
  
• US DOE—United States Department of Energy
  United States Department of Energy
  The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
  
  
• USGS—United States Geological Survey
  United States Geological Survey
  The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology,...
  
  
• UVLS—Under voltage load shedding (electricity)

V

• V—Volt
  Volt
  The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
  
   (measurement)
• VA—Volt-ampere
  Volt-ampere
  A volt-ampere is the unit used for the apparent power in an electrical circuit, equal to the product of root-mean-square voltage and RMS current. In direct current circuits, this product is equal to the real power in watts...
  
   (measurement)
• var—Volt-ampere reactive (measurement)
• VAWT—vertical axis wind turbine
  Vertical axis wind turbine
  Vertical-axis wind turbines are a type of wind turbine where the main rotor shaft is set vertically and the main components are located at the base of the turbine...
  
   (wind)
• VIN—vehicle identification number
  Vehicle identification number
  A Vehicle Identification Number, commonly abbreviated to VIN, is a unique serial number used by the automotive industry to identify individual motor vehicles. VINs were first used in 1954...
  
   (US) (transportation)
• VLCC—very large crude carrier (oil)
• VMT—vehicle miles traveled (transportation)
• VOC—volatile organic compound
  Volatile organic compound
  Volatile organic compounds are organic chemicals that have a high vapor pressure at ordinary, room-temperature conditions. Their high vapor pressure results from a low boiling point, which causes large numbers of molecules to evaporate or sublimate from the liquid or solid form of the compound and...
  
  
• VPP—Variable peak pricing (electricity)
• VSA—Voltage stability analysis

W

• W—Watt
  Watt
  The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
  
  
• WACOG—weighted average cost of gas
• WAMS—Wide area measurement system- see description in phasor measurement unit article. (electricity)
• WCMC—World Conservation Monitoring Centre
  World Conservation Monitoring Centre
  The United Nations Environment Programme's World Conservation Monitoring Centre is an executive agency of the United Nations Environment Programme, based in Cambridge in the United Kingdom. UNEP-WCMC has been part of UNEP since 2000, and has responsibility for biodiversity assessment and support...
  
  
• WCRE—World Commission on Renewable Energy
• WEA—World Energy Assessment
• WEC—World Energy Council
  World Energy Council
  The World Energy Council is a global and inclusive forum for thought-leadership and tangible engagement with headquarters in London. Its mission is 'To promote the sustainable supply and use of energy for the greatest benefit of all people'....
  
  
• WECC—Western Electricity Coordinating Council
  Western Electricity Coordinating Council
  The Western Electricity Coordinating Council was formed on April 18, 2002, from the merger of the Western Systems Coordinating Council which itself was formed on August 14, 1967, the Southwest Regional Transmission Association , and Western Regional Transmission Association...
  
   (US)
• WEEA—World Energy Efficiency Organization
• WH—watthour (measurement)
• WHO—World Health Organisation
• WIRAB—Western Interconnection Regional Advisory Body (US)
• WRI—World Resources Institute
  World Resources Institute
  The World Resources Institute is an environmental think tank founded in 1982 based in Washington, D.C. in the United States.WRI is an independent, non-partisan and nonprofit organization with a staff of more than 100 scientists, economists, policy experts, business analysts, statistical analysts,...
  
  
• WSCC—Western Systems Coordinating Council (US)
• WSPP—Western Systems Power Pool (US)
• WSSD—World Summit on Sustainable Development
• WTG—Wind turbine generator (wind)
• WTI—West Texas Intermediate
  West Texas Intermediate
  West Texas Intermediate , also known as Texas light sweet, is a grade of crude oil used as a benchmark in oil pricing. It is a light and sweet crude oil...
  
   (US)
• WTP—Willingness to pay
  Willingness to pay
  In economics, the willingness to pay is the maximum amount a person would be willing to pay, sacrifice or exchange in order to receive a good or to avoid something undesired, such as pollution...
  
  
• WY—Water Year
  Water year
  A water year is term commonly used in hydrology to describe a time period of 12 months. It is defined as the period between October 1st of one year and September 30th of the next....
  
   (measurement)

Appendix: Residential energy abbreviations

• AFUE—annual fuel utilization efficiency
• BTL—building tightness limit (building tightness)
• CDH—cooling degree hours (climate)
• CFL—compact fluorescent light
• COP—coefficient of performance
• CRI—color rendering index
• EEM—Energy Efficient Mortgage
• EER—energy efficiency ratio
• EF—energy factor (clothes washers)
• EIM—Energy Improvement Mortgage
• ERV—energy-recovery ventilator
• HDD—heating degree day
• HHI—home heating index
• HID—high-intensity discharge
• HRV—heat-recovery ventilator
• HSPF—heating seasonal performance factor
• HVI—Home Ventilating Institute
• IECC—International Energy Conservation Code
• K-value—thermal conductance
• Low-e—low emissivity
• LEED—Leadership in Energy and Environmental Design
  Leadership in Energy and Environmental Design
  Leadership in Energy and Environmental Design consists of a suite of rating systems for the design, construction and operation of high performance green buildings, homes and neighborhoods....
  
  , standard for Green Building design
• MEF—modified energy factor (clothes washers)
• MINHERS—Mortgage Industry National Home Energy Rating Systems Standards
• MVG—minimum ventilation guideline (building tightness)
• MVL—minimum ventilation level (building tightness)
• NAECA—National Appliance Energy Conservation Act
  National Appliance Energy Conservation Act
  The National Appliance Energy Conservation Act is a 1975 piece of legislation by the United States Congress which regulates energy consumption of specific household appliances in the United States. Though minimum Energy Efficiency Standards were first established by the United States Congress in...
  
  
• ODS—oxygen depletion sensor
• RESNET—Residential energy services network
• R-value—thermal resistance
• SC—shading coefficient (windows)
• SEER—seasonal E efficiency ratio
• SHGC—solar heat gain coefficient
• SIR—savings-to-investment ratio (energy conservation investments)
• SLA—Specific leakage area
• SPB—Simple Payback (energy conservation investments)
• SSE—steady-state efficiency
• U-value—thermal transmittance (also called U-factor)
• WF—water factor (clothes washers)