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Achievable Potentialsearch for term

Potential that could be achieved through normal market forces, new state building codes, equipment efficiency, utility energy efficiency programs, and other policies.

Acid Rainsearch for term

Also called acid precipitation or acid deposition, acid rain is precipitation containing harmful amounts of nitric and sulfuric acids formed primarily by sulfur dioxide and nitrogen oxides released into the atmosphere when fossil fuels are burned. It can be wet precipitation (rain, snow, or fog) or dry precipitation (absorbed gaseous and particulate matter, aerosol particles or dust). Acid rain has a pH below 5.6. Normal rain has a pH of about 5.6, which is slightly acidic. The term pH is a measure of acidity or alkalinity and ranges from 0 to 14. (Source: EIA Glossary

Additionalitysearch for term

A framework for evaluating whether projects are deserving of offset credits in climate-change mitigation strategies. If a project would have been undertaken and financially attractive regardless of incentives of any kind, then offering incentives to the project is said to yield no “additionality.” Other financial incentives or offset credits should be offered only to projects that would not have happened but for the offering of credits.

Adjustable Speed Drivesearch for term

A device that varies motor speed by adjusting the frequency of current by mechanical or electronic measures.

Synonyms: adjustable speed drives, ASD, ASDs, variable speed drives, VSD, VSDs
Advanced Metering Infrastructuresearch for term

See Smart Meter.

Advanced Rate Designsearch for term

Rate structures that employ dynamic pricing, where the retail cost of electricity varies according to electric demand.

American Recovery and Reinvestment Act of 2009search for term

Also known as the “stimulus bill,” this legislation included the single largest investment in energy efficiency in history with approximately $20 billion specifically for efficiency. This legislation included funds for the Weatherization Assistance Project, State Energy Offices, and Energy Efficiency and Conservation Block Grants. A large proportion of the stimulus funds related to energy efficiency went to state and municipalities.

Synonyms: ARRA
American Society of Heating, Refrigerating and Air-Conditioning Engineerssearch for term

This is an organization of over 50,000 individuals in the air-conditioning, heating, refrigerating and ventilating fields. Supports the integration of increased energy efficiency in building design via technological enhancements of these systems.

Synonyms: ASHRAE
Auxiliary Power Unitsearch for term

An on-board power unit for a long-haul truck to provide power, cooling, and/or heating for the cab when the truck is parked for extended periods.

Behavior-Based Programssearch for term

Energy efficiency programs that utilize an understanding of how individuals interact with energy in order to decrease energy demand.

Blower Doorsearch for term

A home performance test conducted by a contractor (or energy auditor) to evaluate a home’s air-tightness. During this test a powerful fan mounts into the frame of an exterior door and pulls air out of the house in order to lower the inside air pressure. While the fan operates, the contractor can determine the house’s air infiltration rate and better identify specific leaks around the house.

Btusearch for term

British Thermal Unit: the amount of heat required to raise the temperature of 1 pound of liquid water by 1 degree Fahrenheit at the temperature at which water has its greatest density (approximately 39 degrees Fahrenheit).

Synonyms: British Thermal Unit
Building Commissioningsearch for term

Commissioning is a risk reduction or quality assurance process for new construction projects that operates from pre-design through design, construction, and operations. The purpose of commissioning is to ensure that all components of a building have been designed, installed, tested, and are capable of being operated and maintained in conformity with the design intent. (ASHRAE, 1996)

Bulk Power Systemsearch for term

The part of the overall electricity system that includes the generation of electricity and the delivery of that electricity over high-voltage transmission lines to distribution companies. This includes power generation facilities, transmission lines, interconnections between neighboring transmission systems, and associated equipment. It does not include the local distribution of the electricity to homes and businesses. Source:

Bureau of Economic Analysissearch for term

An agency in the United States Department of Commerce that provides important economic statistics including the gross domestic product of the United States. Its stated mission is to "promote a better understanding of the U.S. economy by providing the most timely, relevant, and accurate economic data in an objective and cost-effective manner."

Bus Rapid Transitsearch for term

A bus system that includes exclusive bus right-of-way in congested parts of the service area. BRT is designed to offer the flexibility of a bus service and the speed of light rail.

Synonyms: BRT
California Low-Emissions Vehiclesearch for term

Standards limiting vehicle tailpipe emissions, originally of criteria pollutants and more recently of greenhouse gas emissions as well.

Synonyms: LEV Program
Camless Valve Actuationsearch for term

An emerging engine technology in which valves are electronically controlled, rather than being opened and closed mechanically through a direct connection to the drive train. Can be used to further refine the combustion process to reduce emissions and improve efficiency.

Capacitorsearch for term

A device that maintains or increases voltage in power lines and improves efficiency of the system by compensating for inductive losses.

Capital Stock Turnover Ratesearch for term

Percentage of installed equipment or assets that is replaced either as it wears out or reaches the end of its economic life. Does not include retrofits.

Central Air Conditionerssearch for term

An HVAC system designed to cool the entire house, in which a large compressor unit located outside drives the process; an indoor coil filled with refrigerants cools air that is distributed through the house via ducts. The same duct system is used with a furnace for forced warm-air heating.

Synonyms: CAC
Chillersearch for term

One or more “chillers” are the heart of the air-conditioning system for most large buildings. Most chillers use a vapor-compression cycle, much like residential equipment, dehumidifiers, and common garden-variety refrigerators. The difference is that the chiller removes heat (cools) from a water or brine loop, which typically serves air handlers that cool zones or floors of the building. The chiller rejects the heat to another water loop, typically one connected to a cooling tower mounted on the roof or near the building.

Coincidental Peaksearch for term

The sum of two or more peak loads that occur in the same time interval.

Coincidental Peak Factorsearch for term

The ratio of annual peak demand savings (kW) from an energy efficiency measure to the annual energy savings (kWh) from the measure; also called Coincidence Factor.

Combined Heat and Powersearch for term

A system by which multiple usable energy outputs (both electricity and steam/heat) are derived from a single fuel supply using an integrated system.

Synonyms: CHP
Compact Fluorescent Lampsearch for term

For a given light output, CFLs use between 20 and 33 percent of the power of equivalent incandescent lamps.

Synonyms: CFL, CFLs, Compact Fluorescent Lamps
Compact Growthsearch for term

Land development in which buildings are grouped in areas of high density to facilitate transit access, permit non-motorized modes of transportation, and preserve open space.

Comprehensive Home Energy Auditssearch for term

An assessment of a home’s energy use that includes a visual inspection, diagnostic testing, analysis, and a list of proposed improvements, ending with guidance to complete the work, or actual completion of the work.

Control Groupsearch for term

A group that is statistically equivalent to the participant group, but does not participate in the experiment except by providing data.

Cooperative Electric Utilitysearch for term

An electric utility legally established to be owned by and operated for the benefit of those using its service. The utility company will generate, transmit, and/or distribute supplies of electric energy to a specified area not being serviced by another utility. Such ventures are generally exempt from federal income tax laws. Most electric cooperatives have been initially financed by the Rural Utilities Service (previously the Rural Electrification Administration), U.S. Department of Agriculture. (Source: EIA Glossary

Corporate Average Fuel Economy Standardssearch for term

Federal standards setting a minimum average miles-per-gallon requirement for all vehicles sold by a given manufacturer.

Synonyms: CAFE
Criteria Pollutantsearch for term

One of the six pollutants for which EPA is required to set National Ambient Air Quality Standards to protect human health and welfare. Criteria pollutants include ozone (ground-level), carbon monoxide, particulate matter, sulfur dioxide, lead, and nitrogen oxides. They are called “criteria” pollutants because the Clean Air Act required EPA to describe the criteria for setting or revising standards. (Source: EPA: America’s Children and the Environment Glossary

Synonyms: criteria pollutants
Critical Peak Pricingsearch for term

Rate structures that employ a high price that comes into effect during “critical peak” periods of high electricity demand, typically with some advance notice to the customer (as much as one day ahead or in some cases only a few hours ahead).

Cumulative Savingssearch for term

Sum of the total annual energy savings over a certain time frame. (For example, if we install a measure for each of two years, the cumulative savings would be the sum of the measure installed in the first year, plus the incremental savings from the savings installed in the second year plus the savings in the second year from the measure installed in the first year.)

Cylinder Deactivationsearch for term

A vehicle technology that saves energy by cutting off fuel to some cylinders when the engine is operating at part load.

Decouplingsearch for term

The separation of a utility's profit from its sales of electricity as a commodity. Instead, a utility's revenue is met by setting a revenue target, then electricity rates are regularly fine-tuned to meet that target.

Demand Destructionsearch for term

Reduction in industrial plant operation or plant closures that result in reductions in energy demand.

Demand Responsesearch for term

The reduction of customer energy usage at times of peak usage in order to help address system reliability, reflect market conditions and pricing, and support infrastructure optimization or deferral.

Demand-Side Managementsearch for term

The planning, implementation, and monitoring of utility activities designed to encourage consumers to modify patterns of electricity usage, including the timing and level of electricity demand. It refers to only energy and load-shape modifying activities that are undertaken in response to utility-administered programs. It does not refer to energy and load-shaped changes arising from the normal operation of the marketplace or from government-mandated energy efficiency standards. Demand-side management covers the complete range of load-shape objectives, including strategic conservation and load management, as well as strategic load growth. (Source: EIA Glossary

Synonyms: DSM
Department of Energysearch for term

A Cabinet-level Department tasked with “promoting America’s energy security through reliable, clean, and affordable energy.” Through the Office of Energy Efficiency and Renewable Energy (EERE), the agency runs programs to promote end-use efficiency, and R&D programs designed to advance energy efficiency technologies.

Synonyms: DOE
Diagnostic Home Energy Surveyssearch for term

An assessment of a home’s energy use that includes a visual inspection and diagnostic testing.

Distributed Energy Resourcesearch for term

Electrical power generation or storage located at or near the point of use, as well as demand side measures.

Synonyms: DER
Distributed Generationsearch for term

Electric power generation located at or near the point of use.

Synonyms: DG
Distributed Powersearch for term

Electrical power generation or storage located at or near the point of use.

Distribution Utilitysearch for term

A utility that is responsible for owning, operating, and maintaining the distribution part of the electric system within an area. (Source:

Dual-Fuel Loopholesearch for term

A provision in federal fuel economy (CAFE) standards allowing manufacturers to take credit toward compliance with the standard for sales of vehicles that can run on an alternative fuel, regardless of the availability of that fuel. These manufacturers receive a small miles-per-gallon credit for use of alternative fuels.

Duct Blastersearch for term

A tool used to diagnose duct leakage. It consists of a calibrated fan capable of blowing up to 1,500 cubic feet per minute (CFM) of air, a pressure tap, and flexible ducting for hook-up with a duct system.

Economic Potentialsearch for term

Potential based on both the technical potential and economic considerations (e.g., system cost, avoided cost of energy).

Efficiency Resource Assessmentsearch for term

An analysis that attempts to estimate potential for energy efficiency under given circumstances. These estimates generally fall into three categories: technical potential, which represents the potential for savings from all available technologies and practices independent of cost; economic potential, which represents the savings from all technologies and practices that are cost effective under some economic criteria; and achievable potential, which represents the savings that would be realized under a given set of market conditions.

Electricity Distributionsearch for term

Regulating voltage to distribution levels and distributing electricity to end-users from substations.

Electricity Generationsearch for term

Converting a primary energy source (e.g. coal, natural gas, or wind) into electricity.

Electricity Transmissionsearch for term

Transport of electricity from the generation source to a distribution substation, usually via power lines.

Emerging Technologysearch for term

A technology or practice that is not yet commercialized but is likely to be commercialized within a period (for example, within five years) or is already commercialized, but currently has a market share of less than about 2%.

Synonyms: ET
Energy Auditsearch for term

An assessment of a home's energy use. These include a number of different types of surveys, including (in increasing order of cost and complexity): online audits, in-home home energy surveys, diagnostic home energy surveys, and comprehensive home energy audits.

Energy Conservationsearch for term

Saving energy by doing with less or doing without (e.g., setting thermostats lower in winter and higher in summer; turning off lights; taking shorter showers; turning off air conditioners; etc.).

Energy Efficiency Measuresearch for term

A particular good or practice that provides an energy efficiency benefit. Upgraded insulation, energy efficient appliances, and adjusting a boiler’s limit control are examples of measures.

Energy Efficiency Potentialsearch for term

The amount of energy savings possible.

Energy Efficiency Resource Standardsearch for term

An Energy Efficiency Resource Standard is a simple, market-based mechanism to encourage more efficient use of electricity and natural gas. An EERS consists of electric and/or gas energy savings targets for utilities, often with flexibility to achieve the target through a market-based trading system. All EERS’s include end-user energy savings improvements that are aided and documented by utilities or other program operators. Some EERS’s include distribution system efficiency improvements. Sometimes used in conjunction with a Renewable Portfolio Standard (RPS).

Synonyms: EERS
Energy Independence and Security Act of 2007search for term

A law passed in 2007 that covered issues from fuel economy standards for cars and trucks to renewable fuel and electricity to training programs for a “green collar” workforce to the first federal mandatory efficiency standards for appliances and lighting. This legislation included many authorizations for the funding of programs and technologies but no actual appropriations, i.e. money. This will be the foundation for many future requests to have actual funding applied to the authorizations created by this law.

Energy Information Administrationsearch for term

Created by the Congress in 1977, EIA is the statistical agency of the U.S. Department of Energy and as such is the nation’s premier source of unbiased energy data, analysis and forecasting. By law, EIA’s products are prepared independently of Administration policy considerations. EIA neither formulates nor advocates any policy conclusions. The Energy Information Administration’s mission is to provide policy-neutral data, forecasts, and analyses to promote sound policy making, efficient markets, and public understanding regarding energy and its interaction with the economy and the environment.

Synonyms: EIA
Energy Management Systemsearch for term

A computerized system for fully automatic control of HVAC, lighting, refrigeration, and other commercial building subsystems in order to accurately manage and monitor indoor temperature, comfort, and environmental quality. An EMS often saves energy and money by operating systems only when needed and by allowing time-of-day scheduling and peak load shedding control.

Synonyms: EMS
Energy Policy Act of 1992search for term

The Energy Policy Act of 1992 was passed to reduce our nation's reliance on foreign petroleum and to improve air quality. Officially known as Public Law 102-486, EPAct includes provisions that address all aspects of energy supply and demand. Major revisions were passed in 2005 and 2007.

Synonyms: EPAct 1992
Energy Policy Act of 2005search for term

Energy Policy Act of 2005 was passed to address growing energy concerns. Officially known as Public Law 109-58, EPAct 2005 provides tax incentives and loan guarantees, new equipment efficiency standards, and other measures.

Synonyms: EPAct 2005
Energy Service Companysearch for term

An energy service company is a professional business providing a broad range of comprehensive energy solutions including designs and implementation of energy savings projects, energy conservation, energy infrastructure outsourcing, power generation and energy supply, and risk management. (Source: Wikipedia

Synonyms: Energy Service Companies, ESCo, ESCO, ESCOs
ENERGY STAR®search for term

ENERGY STAR is a joint EPA-DOE program that encourages energy by improving the energy efficiency of a wide range of consumer and commercial products, enhancing energy efficiency in buildings, and promoting energy management planning for businesses and other organizations. (

Environmental Protection Agencysearch for term

Founded in 1970, this independent agency was designed to “protect human health and safeguard the natural environment.” They regulate a variety of different types of emissions, including the greenhouse gases emitted in energy use. They run several national end-use programs, like EnergyStar, SmartWay, Smart Growth programs, and green communities programs.

Synonyms: EPA
Federal Energy Management Programsearch for term

A Department of Energy program that “works to reduce the cost and environmental impact of the Federal government by advancing energy efficiency and water conservation, promoting the use of distributed and renewable energy, and improving utility management decisions at Federal sites.” (

Synonyms: FEMP
Federal Energy Regulation Commissionsearch for term

A federal agency that has jurisdiction at the federal level (as opposed to jurisdiction at the state level) and “regulates and oversees energy industries in the economic, environmental, and safety interests of the American public.” FERC primarily regulates wholesale energy markets while states primarily regulate retail energy markets. (

Synonyms: FERC
Feebatesearch for term

A policy to strengthen the market for environmentally preferable vehicles by charging a fee or paying a rebate to purchasers, depending on features of the vehicle that affect environmental performance.

Flexible Fuel Vehiclesearch for term

A vehicle whose tank can accept petroleum and non-petroleum fuels. Flex-fuel vehicles in the U.S. today are those that can run on any gasoline-ethanol blend up to 85% ethanol (E85).

Synonyms: FFV
Focus Groupsearch for term

A focus group is a qualitative research technique in which researchers ask a group of people about their perceptions, opinions, beliefs and attitudes towards a product, service, advertisement, idea, etc.. Questions are asked in an interactive group setting where participants are free to talk with other group members. (Source: Wikipedia

Free Ridersearch for term

This evaluation term describes energy efficiency program participants who would have taken the recommended actions on their own, even if the program did not exist.

Fuel Cell Vehiclesearch for term

A vehicle that operates on an electric motor that generates its own electricity through a chemical process using hydrogen fuel and oxygen. FCVs that run on pure hydrogen emit only water and heat as by-products, while FCVs that run on a hydrogen-rich fuel emit small amounts of pollution.

Synonyms: FCV
Fuel Economysearch for term

The number of miles traveled by a given vehicle on a gallon of fuel. For light-duty vehicles, fuel economy is defined for purposes of CAFE compliance as a 55%/45% weighted average of city and highway fuel economies as measured in two EPA laboratory tests. Fuel economy values on the window sticker at the time of sale are generally about 20% lower and better reflect real-world driving.

Fuel Oilsearch for term

A refined liquid petroleum product used in a variety of applications such as space and water heating.

Furnacesearch for term

An HVAC system that works by blowing heated air through ducts that deliver warm air to rooms throughout the house via air registers or grills. Condensing furnaces have a second heat exchanger that recaptures heat from excess water vapor.

Gasoline-Gallon-Equivalentsearch for term

A quantity of fuel containing the amount of energy contained in a gallon of gasoline.

Gerrymanderingsearch for term

A form of boundary delimitation (redistricting) in which electoral district or constituency boundaries are deliberately modified for electoral purposes, thereby producing a contorted or unusual shape.

Global Warmingsearch for term

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

Green Buildingsearch for term

A building that utilizes design and construction practices that dramatically improve the efficiency of its use of resources — including energy, water, and materials — over the complete life cycle of the building, while improving human health and productivity.

Greenhouse Gassearch for term

Gases that trap heat in the atmosphere are often called greenhouse gases. Some, like carbon dioxide, occur naturally and are emitted through both natural processes and human activities, but other greenhouse gases (e.g., fluorinated gases) are created and emitted solely through human activities. The principal greenhouse gases that enter the atmosphere because of human activities are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases.

Synonyms: GHG, greenhouse gases
Heat Pumpsearch for term

An HVAC system that works as a two-way air conditioner, moving heat outside in the summer and scavenging heat from the cold outdoors with an electrical system in the winter. Most use forced warm-air delivery systems to move heated air throughout the house.

Heating, Ventilation, and Air Conditioningsearch for term

The mechanical systems that provide thermal comfort and air quality in an indoor space are often grouped together because they are generally interconnected. HVAC systems include: central air conditioners, heat pumps, furnaces, boilers, rooftop units, chillers, and packaged systems.

Synonyms: HVAC
Henry Hubsearch for term

The market price for natural gas is by convention set at the Henry Hub (which is a physical location in southern Louisiana where a number of pipelines from the Gulf of Mexico originate). Futures and spot market contracts for delivery of gas are traded on the New York Mercantile Exchange (NYMEX), with regional wholesale prices set at key hubs where pipelines originate or come together. These prices are set relative to the Henry Hub price with adders for transportation and congestion.

High Performance Buildingsearch for term

Building performance refers to how efficiently and effectively a building is designed, engineered and operated to serve the needs of its occupants. The term is often used interchangeably with “Green Building” but specifically emphasizes the energy (or water) efficiency and service quality associated with all major operational aspects of a building (HVAC, lighting, envelope, etc), as well as how these interact as one system.

Hot Water Distribution Systemssearch for term

Hot water distribution architecture is critical for water and energy efficiency. For small buildings, the traditional approach is a central water heater, with trunk and branches to serve fixtures. Because the water cools between uses rather often, these systems are associated with user dissatisfaction (long waits for hot water) and great waste of water and energy. Alternatives include structured plumbing, typically with grouped fixtures, pumped demand recirculation, and very small “twig” water lines to serve individual fixtures; “home run” architecture with each fixture served by its own small-diameter line, and point-of-use water heaters to serve remote fixtures. In contrast, hotels and similar hospitality buildings generally use recirculating loops to assure instant access to hot water at all locations. Too many commercial buildings, characterized by small uses of hot water, mimic these systems instead of point-of-use water heating.

In-Home Displaysearch for term

See Smart Meter.

In-Home Home Energy Surveyssearch for term

An assessment of a home's energy use. These include a number of different types of surveys, including (in increasing order of cost and complexity): online audits, in-home home energy surveys, diagnostic home energy surveys, and comprehensive home energy audits.

Incremental Annual Savingssearch for term

Energy savings in one year corresponding to the energy efficiency measures implemented in that same year.

Incremental Costsearch for term

The difference in cost relative to a base case, including equipment and labor cost.

Independent System Operatorsearch for term

Entity that controls and administers nondiscriminatory access to electric transmission in a region or across several systems, independent from the owners of facilities.

Indoor Air Qualitysearch for term

The level of indoor air pollutants in a building, including carbon dioxide (CO2), moisture, volatile organic compounds (VOCs), combustion products, and particulates.

Synonyms: IAQ
Indoor Environmental Qualitysearch for term

The entire indoor experience of a building. In addition to air quality and pollutant control, IEQ can include acoustics, lighting/glare, thermal comfort, building controls, and design.

Synonyms: IEQ
Induced Demandsearch for term

Demand for highway capacity that is generated by the construction of new lane miles.

Industrial Ecologysearch for term

The shifting of industrial process from linear (open loop) systems, in which resource and capital investments move through the system to become waste, to a closed loop system where wastes become inputs for new processes.

Integrated Resource Plansearch for term

A comprehensive and systematic blueprint developed by a supplier, distributor, or end-user of energy who has evaluated demand-side and supply-side resource options and economic parameters and determined which options will best help them meet their energy goals at the lowest reasonable energy, environmental, and societal cost. (Source:

Synonyms: IRP, integrated resource plans, integrated resource planning
Interconnectionsearch for term

For all distributed generation – solar, wind, CHP, fuel cells, etc. – interconnection with the local electric grid provides back-up power and an opportunity to participate in net-metering and sell-back schemes when they are available. It’s important to most distributed generation projects to be interconnected with the grid, but adding small generators at spots along an electric grid can produce a number of safety concerns and other operational issues for a utility. Utilities, then, generally work with their state-level regulatory bodies to develop interconnection standards that clearly delineate the manner in which distributed generation systems may be interconnected.

Investor-Owned Utilitysearch for term

Also known as a private utility, IOU's are utilities owned by investors or shareholders. IOU's can be listed on public stock exchanges.

Synonyms: IOU
kWsearch for term

Kilowatt: 1000 W (watts), or 1/1000th of a MW (megawatt), of power.

Synonyms: kilowatt
kWhsearch for term

Kilowatt-hour: A unit of energy used to measure electricity, measured as 1 kilowatt (1,000 watts) of power expended for 1 hour. One kWh is equivalent to 3,412 Btu (British Thermal Units).

Synonyms: kilowatt-hour
Leadership in Energy and Environmental Designsearch for term

A green building rating system, developed by the U.S. Green Building Council (USGBC) in 1998. It provides a suite of standards for environmentally sustainable construction in both residential and commercial building sectors based on a scoring system comprising a set of required "prerequisites" and a variety of "credits" in six major categories. The six categories are siting, water use, energy use and local emissions, materials, indoor environmental quality, and design process.

Synonyms: LEED
Lean-Burnsearch for term

In reference to a combustion process, using less fuel than a stoichiometric fuel-air mix requires. Virtually any diesel motor uses lean-burn combustion, while a lean-burn gasoline engine is an innovation now entering the vehicle market.

Levelized Costsearch for term

The level of payment necessary each year to recover the total investment and interest payments (at a specified interest rate) over the life of the measure.

Liquefied Natural Gassearch for term

Natural gas that is chilled to the point that it is a liquid at atmospheric pressure. Used when storing natural gas locally for extended periods or transporting it for long distances, usually by ship.

Load Managementsearch for term

Load management programs seek to lower peak demand during specific, limited time periods by temporarily curtailing electricity usage or shifting usage to other time periods. Load management reduces system peak demand very well, but can have little or no effect on total energy use. Its effects are temporary and of short duration.

Load Shiftingsearch for term

Policies and technologies that shift electricity consumption from periods of high demand to periods of low demand. These can include rate structures as well as technologies such as energy storage.

Local Distribution Companysearch for term

A legal entity engaged primarily in the retail sale and/or delivery of natural gas through a distribution system that includes mainlines (that is, pipelines designed to carry large volumes of gas, usually located under roads or other major right-of-ways) and laterals (that is, pipelines of smaller diameter that connect the end-user to the mainline). Since the restructuring of the gas industry, the sale of gas and/or delivery arrangements may be handled by other agents, such as producers, brokers, and marketers that are referred to as "non-LDC." (Source: EIA Glossary

Synonyms: LDC
Locational Marginal Pricingsearch for term

Under LMP, the price of energy at any location in a network is equal to the marginal cost of supplying an increment of load at that location.

Synonyms: LMP
Market Transformationsearch for term

The strategic process of intervening in a market to create lasting change in market behavior by removing identified barriers or exploiting opportunities to accelerate the adoption of all cost-effective energy efficiency as a matter of standard practice.

Synonyms: MT
Mcfsearch for term

One thousand cubic feet.

Millssearch for term

A monetary cost and billing unit used by utilities; it is equal to 1/1000 of the U.S. dollar (equivalent to 1/10 of 1 cent). (Source: EIA Glossary

Minimum Efficiency Standardssearch for term

Regulations carrying the force of law that prohibit sale or installation of products that fail to provide at least some specified level of energy performance, typically based on a ratio of service provided (such as warm air provided by a furnace) to energy input. A very specific test procedure or rating method is required for each efficiency standard, to assure consistency between manufacturers. Many programs are monitored by testing at third-party labs in trade association programs.

MMBtusearch for term

One million Btus (British Thermal Units).

Synonyms: Million British Thermal Units
Multimodal Transportationsearch for term

The integrated use of several means of passenger or freight transportation.

MWsearch for term

Megawatt: 1000 kW (kilowatts), or 1,000,000 W (watts) of power.

Synonyms: Million Watts
MWhsearch for term

Megawatt-hour: Equivalent to 1000 kWh (kilowatt-hours), or 1,000,000 Wh (watt-hours), of energy.

Synonyms: Million Watt-Hours
National Appliance Energy Conservation Act of 1987search for term

Officially known as Public Law 100-12, this legislation established minimum efficiency standards for many household appliances. These included: refrigerators, refrigerator-freezers, and freezers; room air conditioners; fluorescent lamp ballasts; incandescent reflector lamps; clothes dryers; clothes washers; dishwashers; kitchen ranges and ovens; pool heaters; and water heaters. Congress set initial federal energy efficiency standards and established schedules for DOE to review these standards.

National Highway Traffic Safety Administrationsearch for term

Part of the U.S. Department of Transportation, sets fuel economy (CAFE) standards, as well as vehicle safety requirements.

Synonyms: NHTSA
Natural Gas Vehiclesearch for term

A vehicle that runs on compressed or liquefied natural gas. These vehicles produce significantly fewer tailpipe and greenhouse gas emissions than vehicles that run on conventional gasoline or diesel.

Synonyms: NGV
Net-to-Grosssearch for term

Net-to-gross ratios are important in determining the actual energy savings attributable to a particular program, as distinct from energy efficiency occurring naturally (in the absence of a program). The net-to-gross ratio equals the net program load impact divided by the gross program load impact. This factor is applied to gross program savings to determine the program's net impact. Adapted from the California Public Utilities Commission Website:

North American Electric Reliability Corporationsearch for term

NERC’s mission is to improve the reliability and security of the bulk power system in North America. To achieve that, NERC develops and enforces reliability standards; monitors the bulk power system; assesses future adequacy; audits owners, operators, and users for preparedness; and educates and trains industry personnel. NERC is a self-regulatory organization that relies on the diverse and collective expertise of industry participants. As the Electric Reliability Organization, NERC is subject to audit by the U.S. Federal Energy Regulatory Commission and governmental authorities in Canada. (Source: NERC

Synonyms: NERC
North American Industry Classification Systemsearch for term

A coding classification system used in U.S. and Canada to group various companies or entities by their area of economic activity. See for details.

Synonyms: NAICS
Off-Peaksearch for term

Periods of relatively low system demand. These periods often occur in daily, weekly, and seasonal patterns; these off-peak periods differ for each individual electric utility. (Source: EIA Glossary

Online Auditsearch for term

A type of energy audit, specifically a Web-based interactive tool assessing home energy use.

Operation and Maintenancesearch for term

Activities undertaken during the normal operation of a facility in order to operate equipment and maintain it in good condition. Improving O&M practices are a low-cost measure for increasing energy efficiency in commercial buildings and industrial facilities.

Synonyms: O&M
Packaged Systemsearch for term

At minimum, an air conditioner in which all components are mounted in a single cabinet designed to be installed on the roof or adjacent to a building. Components include compressor, evaporator, condenser, fan, filter, and controls. Usually includes a heating section (resistance, heat pump, or “gas-pak”). May (should) include controllable ventilation capability to assure indoor air quality; frequently lacking in small systems.

Parking Cash-Outsearch for term

A workplace policy that offers employees the cash value of a parking space in exchange for their getting to work without driving.

Pay-As-You-Drive Insurancesearch for term

An insurance policy in which the premium is determined to a large extent by the number of miles traveled by the policy holder.

Synonyms: PAYD Insurance
Peak Demandsearch for term

The highest level of electricity demand during the year for a particular service area (e.g., customer, service territory, or state), measured in kilowatts (kW) or megawatts (MW).

Peak Shavingsearch for term

Technologies or programs that reduce electricity demand only during peak periods (sometimes combined with "valley filling" policies that seek to increase consumption to periods of low demand: the combination is referred to as load shifting.)

Plug-in Hybrid-Electric Vehiclesearch for term

A vehicle that can run on a battery that can be plugged into an electrical source for recharging. PHEVs, like other hybrid vehicles, have both an electric motor and an internal combustion engine. Non-plug-in hybrid batteries are recharged as the user drives.

Synonyms: PHEV
Post-Occupancy Evaluationsearch for term

A process of systematically evaluating the performance of buildings after they have been built and occupied for some time. POE differs from other evaluations of building performance in that it focuses on the requirements of building occupants, including health, safety, security, functionality, efficiency, psychological comfort, aesthetic quality, and satisfaction.

Synonyms: POE
Power Poolsearch for term

Two or more inter-connected electric systems planned and operated to supply power in the most reliable and economical manner for their combined load requirements and maintenance programs.

Public Benefit Programssearch for term

These programs are efficiency and/or low-income customer assistance activities at the state level that are funded by relatively small charges added to utility bills. Utilities, state agencies, and/or private contractors administer the programs; state agencies oversee them. (Adapted from WRAP:

R&Dsearch for term

Research and Development. Refers to creative work undertaken on a systematic basis in order to increase the stock of knowledge—including knowledge of humans, culture, and society—and the use of this stock of knowledge to devise new applications. R&D is critical to advancing energy efficiency by promoting the creation, development, and commercialization of new, energy-efficient technologies and practices.

Synonyms: RD&D, RD&DD, Research, Development and Deployment, Research, Development, Deployment, and Demonstration
Rate Casesearch for term

A proceeding, usually before a regulatory commission, involving the rates to be charged for a public utility service. (Source: EIA Glossary

Ratepayer Impact Measure Testsearch for term

This cost-effectiveness test measures what happens to customer bills or rates due to changes in utility revenues and operating costs caused by the program. The test excludes other benefits such as reliability, environmental effects, non-economic benefits, and avoided collection costs. (Adapted from the California Public Utilities Commission Standard Practice Manual:

Synonyms: RIM Test
Real Time Pricingsearch for term

Rate structure under which rates vary continuously according to the wholesale price of electric power.

Rebound Effectsearch for term

The tendency for a motorist to increase her/his annual miles driven upon obtaining a more efficient vehicle. Rebound is therefore one manifestation of the elasticity of driving with respect to fuel costs, which has been shown to fall in recent years in the range of -0.05 to -0.1 in the short term, meaning that for each one percent increase in fuel costs, miles driven falls by 0.05 to 0.1%.

Recycled Energysearch for term

Thermal or mechanical energy that is recovered from an existing system with out the need for additional fuel. Also referred to as “recovered waste energy.” Examples of recycled energy include: steam generated from heat recovery from a steel blast furnace; mechanical power generated from replacing a pressure reducing valve with a backpressure turbine; and mechanical energy recovered by an elevator as it descends.

Regional Greenhouse Gas Initiativesearch for term

A cooperative cap-and-trade initiative undertaken by the Northeastern and Mid-Atlantic states to reduce carbon dioxide emissions. To address the important climate (greenhouse gas reductions) issue, the RGGI participating states developed and are implementing a regional program for reducing emissions through the implementation of a multi-state market-based emissions trading system. Similar initiatives are being planned in the Midwest, through the Midwestern Greenhouse Gas Accord, and in the West, through the Western Climate Initiative.

Synonyms: RGGI
Regional Reliability Councilsearch for term

Regional entities representing members from all segments of the electric generation sector in a region. These councils work with NERC to develop and enforce reliability standards. There are eight RRCs in North America.

Synonyms: RRC
Regional Transmission Organizationsearch for term

An independent regional transmission operator and service provider that meets certain criteria, including those related to independence and market size.

Synonyms: RTO
Renewable Generationsearch for term

Electric power generation from a renewable energy source such as wind, solar, sustainably harvested biomass, or geothermal.

Replace-on-Burnoutsearch for term

Replacing equipment when it fails in normal operation with a more energy-efficient technology. Cost basis is the incremental cost of choosing a more efficient technology over a less efficient one.

Retrocommissioningsearch for term

Retrocommissioning, or existing building commissioning, is a systematic process for identifying and implementing operational and maintenance improvements in a building and ensuring continued performance over time. Retrocommissioning intends to optimize the operation and maintenance of building subsystems as well as how the systems function together. The RCx process focuses on O&M improvements and diagnostic testing rather than capital improvements (although some needed capital improvements may be recommended as a result).

Synonyms: RCx
Retrofitsearch for term

A retrofit involves the installation of new, usually more efficient equipment into an existing building or process prior to the existing equipment's failure or end of its economic life. In buildings, retrofits may involve either structural enhancements to increase strength, or replacing major equipment central to the building's functions, such as HVAC or water heating systems. In industrial applications, retrofits involve the replacement of functioning equipment with new equipment.

Retrofit Measuresearch for term

Replacing currently functioning equipment with a more energy-efficient technology before its end of life. Cost basis is the full cost of the new technology, including labor.

Roof-Top Unitsearch for term

Packaged heating, ventilating, and air-conditioning unit that generally provides air-conditioning and ventilating services for zones in low-rise buildings. RTUs often include a heating section, either resistance electric, heat pump, or non-condensing gas (the latter are called “gas-paks”). RTUs are the most prevalent comfort conditioning systems for smaller commercial buildings. Generally small (<10 ton) commodity products, but very sophisticated high efficiency versions are available, as are units larger than 50 tons.

Synonyms: RTU
Rulemakingsearch for term

The authority delegated to administrative agencies by Congress or state legislative bodies to make rules that have the force of law. Frequently, statutory laws that express broad terms of a policy are implemented more specifically by administrative rules, regulations, and practices. (Source: EIA Glossary

Rural Electric Cooperativesearch for term

Nonprofit, cooperative utilities that provide electricity to rural areas and are owned by all customers of that utility.

Satisficingsearch for term

The act of meeting a base need and achieving a desired/optimum level of need. Energy efficiency efforts should aim to yield an equal or higher level of satisficing versus what was done before the efficiency efforts were deployed. Sacrifice should not be required.

Single-Action Biassearch for term

The belief that one solution will solve a particular problem. Once one action is taken to solve a problem, there is a reluctance to take more action beyond the first attempt.

Smart Metersearch for term

An advanced electricity meter that uses real time sensors to provide information on power consumption and price. (Adapted from Mondaq: United States: Glossary of Key Climate Change Terms:

SmartWay Programsearch for term

A voluntary program of the Environmental Protection Agency that aims to reduce transportation-related emissions by identifying practices and products (such as vehicles) that reduce emissions of greenhouse gases and criteria pollutants. The SmartWay Program targets shippers and carriers, and manufacturers of light-duty vehicles.

Social Marketingsearch for term

A targeted message that is sent to a particular set of individuals with similar tastes, interests and demographics, in the interest of motivating a particular behavioral outcome toward improving a social good.

Social Normssearch for term

The appropriate and inappropriate expectations and behaviors within a group of individuals. These norms influence how human beings interact and make decisions within their surroundings.

Social Rationalizationsearch for term

How an individual values the decisions and actions that s/he has made as an individual given his/her identity and social norms.

Societal Cost Testsearch for term

The benefit-cost test that evaluates programs from a broad societal perspective. It is identical to the Total Resource Cost test except that the benefits include beneficial externalities and the costs can include negative externalities. Benefits can include avoiding environmental or social externalities (e.g., reduced pollutant emissions) and “non-price” benefits enjoyed by participants (improved comfort, aesthetic qualities, etc.). (Source: Glossary of Selected Terms Used in Utility Deregulation

South-Central Partnership for Energy Efficiency as a Resourcesearch for term

The Sourth-central Partnership for Energy Efficiency as a resource (SPEER) is the regional energy efficiency organization (REEO) that promotes the adoption of advanced building systems and energy efficient products and services in Texas and Oklahoma (

Synonyms: SPEER
Spilloversearch for term

This evaluation term describes energy efficiency program participants who take the recommended actions, but never claim the incentives.

Standard Industrial Classification Systemsearch for term

Standard Industrial Classification system was used prior to NAICS to classify the areas of economic activity for a firm or entity. The SIC system was superseded by NAICS in 1997, but is still in frequent use by many utilities and other groups. Because of fundamental differences between the structure of the two systems, it is not possible to do a direct translation from one system to another. (Condordance between SIC and NAICS codes)

Synonyms: SIC System
Supply-Sidesearch for term

In the utility industry, the term “supply-side” refers to new sources of energy (including both renewable sources and fossil fuels). These resources are sometimes contrasted with the “demand-side” resources that utilities can access through energy efficiency programs.

System Benefits Chargesearch for term

A charge on a consumer's bill from an electric distribution company that helps pay for the costs of certain public benefits program such as low-income assistance, energy efficiency programs, and public interest R&D efforts.

Technical Potentialsearch for term

Potential based on technological limitations only (no economic or other considerations).

Thermal Envelopesearch for term

The conceptual and physical boundary between the parts of a building that are heated and cooled vs. those in which temperature and humidity are not intentionally controlled.

Tier 2 Standardssearch for term

Federal standards for vehicles and fuels for the purpose of reducing criteria pollutant emissions. Vehicles on sale in the United States must be certified to either Tier 2 standards or California low emissions vehicle (LEV) standards.

Time of Use Ratessearch for term

Rate structure that employs standard differentiated prices for electricity consumed during on-peak and off-peak periods, which are generally consistent throughout the year. In some cases TOU rates also include seasonal price differentiation.

Synonyms: TOU Rates
Total Annual Savingssearch for term

Energy savings occurring in a single year from the energy efficiency measures implemented in that year and from measures installed in prior years that are continuing to provide benefits. Sum of all Incremental Annual Savings.

Total Resource Cost Testsearch for term

A benefit-cost test that includes both the participants' and the utility's costs. The benefits for the TRC are avoided energy supply costs. Avoided credit and collection costs should also be included, as they are system costs. The costs in this test are the program costs (including equipment costs) paid by both the utility and the participants, plus the increase in supply costs for any period in which load has been increased. Sometimes includes externalities: see Societal Cost test (Source:

For more information, see the California Public Utilities Commission Standard Practice Manual:

Synonyms: TRC Test
Transformersearch for term

Electrical device that changes the voltage in circuits, commonly used to lower the voltage from high-voltage transmission lines to low-voltage distribution lines.

Truck Stop Electrificationsearch for term

A system of electric connections at truck stop spaces that either allow truckers to plug in their vehicles or provide heating and cooling to eliminate long-term idling to power accessory systems.

Turbochargingsearch for term

Increasing the compression ratio of an internal combustion engine using energy captured by passing exhaust gases through a turbine.

Utility Cost Testsearch for term

A benefit-cost test that measures the net costs of a program based on the costs incurred by the utility (including incentive costs) and excluding any net costs incurred by the participant. The benefits for the Utility Cost Test are the avoided supply costs of energy and demand. Avoided credit and collection costs should also be included, as they are system costs. The costs for the Utility Cost test are the program costs incurred by the utility, the incentives paid to the customer, and any increased supply costs. (Source: Glossary of Selected Terms Used in Utility Deregulation

Utility Restructuringsearch for term

The process of changing the structure of the electric power industry from one of guaranteed monopoly over service territories, as established by the Public Utility Holding Company Act of 1935, to one of open competition between power suppliers for customers in any area. (Source: Electro Industries Glossary

Variable Valve Timingsearch for term

Advancing or delaying the opening or closing of engine valves to refine the combustion process, thereby reducing fuel consumption.

Vertical Integrationsearch for term

Refers to the traditional electric utility structure, whereby a company has direct control over its transmission, distribution, and generation facilities and can offer a full range of power services.

Weatherizationsearch for term

The activity of making a building (generally a residential structure) more energy efficient by reducing air infiltration, improving insulation, and taking other actions to reduce the energy consumption required to heat and/or cool the building. In practice, “weatherization programs” may also include other measures to reduce energy used for water heating, lighting, and other end uses.

Wholesale Competitionsearch for term

A system in which a distributor of power would have the option to buy its power from a variety of power producers, and the power producers would be able to compete to sell their power to a variety of distribution companies.

Wholesale Electricitysearch for term

Power that is bought and sold among utilities, non-utility generators, and other wholesale entities, such as municipalities.

Wholesale Power Marketsearch for term

The purchase and sale of electricity from generators to resellers (that sell to retail customers) along with the ancillary services needed to maintain reliability and power quality at the transmission level.