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industry acronyms


Tri-County Regional Energy Network

Description: 3C-REN (Tri-County Regional Energy Network) is a partnership between the Counties of San Luis Obispo, Santa Barbara and Ventura established to deliver energy-saving programs and industry trainings that help reduce energy use, strengthen local job markets, and support efforts to achieve climate goals.


American Council for an Energy-Efficient Economy

Description: Nonprofit research organization

Function: Develops transformative policies to reduce energy waste & combat climate change


Air Changes Per Hour

Description: Measurement related ventilation

Function: Used to quantify fresh air in buildings

Notes: Determine air infiltration = how tight or leaky the building envelope is.


Avoided-Energy Supply Costs

Description: Incremental cost to a utility of generating or purchasing electric energy or capacity, or both, in an amount equal to that purchased from the qualifying facility


Advanced Metering Infrastructure

Description: Integrated system of smart meters, communications networks, and data management systems

Function: Enables two-way communication between utilities and customers


American National Standards Institute

Description: Private non-profit organization that administers and coordinates the US voluntary standards and conformity assessment system

Function: Identifies, develops standards-conformance-based solutions to national & global priorities


Air Quality Management District

Description: Defined geographical areas where air pollution levels are, or are likely to, exceed national air quality objectives

Function: Identify and monitor where the public may be exposed to harmful air pollution over a period of time e.g. residential homes, schools etc.


American Recovery and Reinvestment Act

Description: Stimulus package enacted by Congress, signed into law by President Obama in Feb 2009

Function: A greater increase in poverty was averted by ARRA which provided funds to create, preserve jobs, extend or expand unemployment insurance, other safety net programs


Air-source Heat Pump

Description: Type of heat pump that can absorb heat from outside a structure and release it inside using vapor-compression refrigeration process, in reverse


Bay Area Air Quality Management District

Description: The California Legislature created the Air District in 1955 as the first regional air pollution control agency in the country.

Function: The Air District is tasked with regulating stationary sources of air pollution in the nine counties that surround San Francisco Bay: Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, southwestern Solano, and southern Sonoma counties.


Bay Area Regional Energy Network

Description: The Bay Area Regional Energy Network is a coalition of the Bay Area’s nine counties — a network of local governments partnering to promote resource efficiency at the regional level, focusing on energy, water and greenhouse gas reduction.


Building Decarbonization Coalition

Description: The Building Decarbonization Coalition aligns critical stakeholders on a path to transform the nation’s buildings through clean energy, using policy, research, market development and public engagement.


Building Performance Association

Description: Member organization

Function: Represents EE industry

Notes: Merger of HPC, HEM, EFN and BPI


Building Performance Institute

Description: Education and training

Function: Certifications

Notes: Part of BPA


Behavior, Retro Commissioning, and Operational Efficiencies

Description: EE savings, not directly from equipment

Function: Considers impacts of complete solutions

Notes: Much of this is related to behavior


British Thermal Unit

Description: A measure of heat  energy

Function: Determine heating capacity or needs

Notes: Roughly equal to the heat output of one wooden match


California Energy Efficiency Coordinating Committee

Description: Provides a venue for stakeholders to discuss energy efficiency matters under the purview of the CPUC while ensuring transparent access to information and opportunities to get involved.


California Independent Systems Operator

Description: Independent grid operator

Function: Load manager for the CA electrical grid

Notes: Predicts demand and directs resources across the 26k miles of electrical distribution lines in CA


California Air Resources Board

Description: Regulatory body

Function: Oversees Air Quality Districts

Notes: Responsible for protecting the public from the harmful effects of air pollution


Community Choice Aggregator

Description: A local government entity that provides consumers an option to IOUs

Function: Provide the public choice over their energy sources

Notes: AB 117 passed in 2002 allowing CCAs – also known as CCEs


Community Choice Energy

Description: A local government entity that provides consumers an option to IOUs

Function: Provide the public choice over their energy sources

Notes: AB 117 passed in 2002 allowing CCEs – also known as CCAs


Carbon Capture and Storage

Description: Process in which stream of industrial carbon dioxide is separated, treated, transported to a long-term storage location


Comprehensive Design Approach

Description: A unique interdisciplinary approach to housing design

Function: Design to maximize occupants’ well-being, minimize environmental load


Clean Energy Connection

Description: EFCA Contractor Directory

Function: Our contractor directory allows homeowners to connect with local, vetted contractors with proven expertise and trustworthiness on clean energy and electrification projects.


California Energy Commission

Description: State agency

Function: Responsible for building codes and enforcement

Notes: Located in Sacramento


Cubic Feet per Minute

Description: A measurement of flow

Function: Quantify volume

Notes: Can be applied to liquids and gasses


CFM @ 25 Pascals

Description: A reference pressure measurement

Function: Standard pressure reference for Air Duct testing

Notes: Allows you to quantify how leaky duct systems are


CFM @ 50 Pascals

Description: A reference pressure measurement

Function: Standard pressure reference used for Blower Door testing

Notes: Allows you to quantify building envelope (shell) infiltration (air leaks)



Description: Natural occurring gas

Function: Main component of Natural Gas

Notes: GWP of 28-36


Carbon Dioxide

Description: Natural occurring gas

Function: Used as baseline in GHG conversations


Coefficient of Performance

Description: Ratio of useful heating or cooling provided to work required

Function: Higher COPs equate to higher efficiency, lower energy consumption, lower operating costs


California Public Utilities Commission

Description: State agency

Function: Regulatory body

Notes: Provide oversite of investor owned utilities (regulated monopolies). Main office in SF


Distributed Energy Resources

Description: Electricity production and storage from small grid connected sources

Function: Simple term to describe non-utility produced electricity

Notes: Renewables, Wind, solar, etc


Deep Energy Retrofit

Description: Categorized as an energy conservation measure in an existing building

Function: Leading to an overall improvement in the building performance


Distributed Energy Resource Management

Description: Software solutions that control, coordinate a variety of DERs

Function: DERs are energy types such as Solar, Wind, battery storage, amongst others


Department of Energy Resources

Description: Massachusetts DOER’s mission: develop, implement policies, programs ensuring the adequacy, security, diversity, cost-effectiveness of the Commonwealth’s energy supply

Function: To create a clean, affordable and resilient energy future for all residents, businesses, communities, institutions


U.S. Department of Transportation

Description: Mission: Deliver world’s leading transportation system

Function: Serving the American people and economy through the safe, efficient, sustainable, and equitable movement of people and goods


Demand Response

Description: Remote control of appliances in response to loads

Function: Third party controls to reduce load during peak demand

Notes: A grid loss management tool. Typically controlled by a Utility to reduce loads during high demand periods


Energy Distribution Company

Description: Responsible for getting electricity from the supplier to your home or business

Function: They own and operate the powerlines, substations and cables that transfer energy


Energy Efficiency

Description: Short for Energy Efficiency

Function: Often used in policy conversations related to EE


Energy Efficiency Advisory Council

Description: Guides the progress of energy efficiency ensuring our continuing leadership in implementation, integration, innovation


Energy Efficiency Ratio

Description: Ratio of a heating or cooling system’s output, per hour, in British thermal units to the input in watts

Function: Used to measure the system’s efficiency


Efficiency First California

Description: Member organization

Function: Represents EE and Clean Energy Industries

Notes: Was a chapter of EFN – which merged into BPA in 2019


Efficiency First National

Description: Member organization

Function: Represents EE

Notes: Merged with 3 other organizations to form BPA


Electric & Gas Industries Association

Description: An industry-leading nonprofit organization helping contractors achieve success through education, training, services, tools


Energy Information Administration

Description: Collects, analyzes, disseminates independent impartial energy info to promote sound policymaking, efficient markets, and public understanding of energy and its interaction with the economy and environment


Environmental Impact Statement

Description: Document, under USA environmental law required by the 1969 National Environmental Policy Act for certain actions “significantly affecting the quality of the human environment”

Function: An EIS is a tool for decision making


Energy Independence and Security Act

Description: EISA reinforced the federal energy reduction goals in Executive Order 13423 & introduced more aggressive requirements

Function: Three key provisions: Corporate Average Fuel Economy Standards, Renewable Fuel Standard, Appliance/lighting efficiency standards


Envelope/Enclosure Leakage Ratio

Description: The area of an orifice that would produce the same amount of leakage as the building envelope at the reference pressure

Function: In climate zone 2 the ELR must be 5 Air Changes per Hour or less, tested at 50 Pascals (ACH50). In climate zones 3 and 4 the ACH50 must be 3 or less


Evaluation, Measurement, and Verification

Description: Incentive program analysis

Function: Used to determine effectiveness of incentives

Notes: Often used after a program has been in operation to determine effectiveness


U.S. Environmental Protection Agency

Description: EPA’s mission is to protect human health and the environment


Electric Power Research Institute

Description: Delivers independent, objective thought leadership, industry expertise to help the energy sector identify issues, technology gaps, and broader needs that can be addressed through effective, collaborative research and development programs

Function: Collaborates with more than 450 companies in 45 countries, driving innovation to ensure the global public has clean, safe, reliable, affordable, equitable access to electricity


Electric Reliability Council of Texas

Description: Serve the public by ensuring a reliable grid, efficient electricity markets, open access and retail choice


Federal Housing Administration

Description: Part of the USA Department of Housing and Urban Development, provides mortgage insurance on loans made by FHA-approved lenders

Function: FHA mortgage insurance protects lenders against losses; because lenders have less risk, they can offer more mortgages to homebuyers


Grid-Enhancing Technologies

Description: Set of technologies designed to allow existing grid infrastructure to transport more electricity

Function: Most common: dynamic line ratings (DLRs), advanced power flow controls, and topology optimization


Green House Gas

Description: Gas that contributes to global warming

Function: Identify gases causing global warming

Notes: CO2 ia s GHG, Methane and many others are too


Grid Modernization Plan

Description: Focuses on development of new architectural concepts, tools, technologies that measure, analyze, predict, protect, control the grid of the future

Function: Enabling the institutional conditions for more rapid development and widespread adoption of these tools and technologies


Gallons per minute

Description: Measurement of the volume of fluid moved over time

Function: Measure flow of liquids

Notes: Typically used in reference to water but applies to all liquids


Ground-source Heat Pump

Description: Building heating/cooling system that uses a type of heat pump to transfer heat to or from the ground

Function: Takes advantage of the relative constancy of temperatures of the earth through the seasons


Gas Service Representative

Description: Gas Utility employee

Function: Field technician

Notes: Primary responder for Natural  Gas related issues


Giga Watt Hours

Description: Unit of energy representing one billion (1,000,000,000) watt hours, equivalent to one million kilowatt hours

Function: Gigawatt hours are often used as a measure of the output of large electricity power stations


Global Warming Potential

Description: A scale used to compare impacts of GHG gasses

Function: Used to measure impacts on ozone layer

Notes: CO2 has GWP of 1, Methane GWP 28-36,


Global Warming Solutions Act

Description: Global Warming Solutions Act of 2006, (Assembly Bill 32), is a CA State Law that fights global warming

Function: Reduces greenhouse gas emissions from all sources throughout the state by establishing a comprehensive program


Home Energy Rating System

Description: Program is designed to identify, fix issues, recognize areas for improvement, and compare the energy efficiency of California’s homes

Function: HERS Index is the industry standard for measuring a home’s energy efficiency


Home Performance Contractors

Description: Contractors committed to clean energy initiatives, including electrification and home performance services


Heat Pump Space Heating

Description: Using a heat pump to provide heat

Function: Electric heating option

Notes: Most efficient way to heat building


Heat Pump Water Heating

Description: Using a heat pump to provide hot water

Function: Electric water heating option

Notes: Most efficient way to heat water


Indoor Air Quality

Description: A measurement of particulates and other factors

Function: Used as a metric to determine health impacts of indoor air

Notes: Humidity, ventilation, particulates, combustion by products, off gassing, are all factors that affect IAQ


Investor Owned Utility

Description: Regulated Monopolies

Function: Provide Natural Gas or Electricity

Notes: There are 4 IOUs in California



Description: Spectrum of light. Outside the range of human vision

Function: IR cameras can be used to see heat

Notes: Often used as part of an Energy Audit


Inflation Reduction Act

Description: IRA will make a historic investment in domestic energy production and manufacturing, and reduce carbon emissions by roughly 40 percent by 2030


Independent System Operators

Description: Independent organization for electric grid operations, market facilitation for certain electric markets, and bulk electric system planning

Function: ISOs were created to facilitate competitive wholesale electric markets


Inches of water column

Description: A measurement unit for measuring static pressure; a key metric for determining how much resistance air must overcome in order to reach the area it’s supposed to heat or cool

Function: Excessive static pressure will prevent an HVAC from operating as efficiently or effectively as it should



Description: A measure of 1,000 watts of electrical power


Kilowatt Hours

Description: A kilowatt-hour is a unit of energy: one kilowatt of power for one hour, equal to 3.6 megajoules

Function: Kilowatt-hours are a common billing unit for electrical energy delivered to consumers by electric utilities


Lawrence Berkeley National Laboratory

Description: A U.S. Department of Energy National Laboratory Managed by the University of California, the nation’s leading public university

Function: Berkeley Lab’s collective purpose is to serve humankind through science


Leadership in Energy and Environmental Design

Description: The most widely used green building rating system

Function: LEED certification is a globally recognized symbol of sustainability achievement


Liquefied Natural Gas

Description: Natural gas that has been cooled down to liquid form for ease and safety of non-pressurized storage or transport

Function: It takes up about 1/600th the volume of natural gas in the gaseous state


Liquefied Propane

Description: Also known as liquefied petroleum gas (LPG) propane is a clean-burning alternative fuel

Function: It is the world’s third most common transportation fuel, behind gasoline and diesel, and is considered an alternative fuel under the Energy Policy Act of 1992


Memorandum of Agreement

Description: Legal document describing a business partnership between two parties that have agreed to cooperate to meet an agreed objective or complete a project

Function: MOAs establish common legal terms for a conditional agreement where the transfer of funds for services are anticipated


Memorandum of Understanding

Description: Document that describes the broad outlines of an agreement that two or more parties have reached

Function: MOUs tend to be used for simple common-cause agreements which are not legally binding


Mega Volt Amps

Description: Measure of active and reactive electrical power equal to one million volt-amperes

Function: Equal to 1000 Kilovolt-Amperes


National Association of Home Builders

Description: NAHB is a Federation of state and local home builder associations

Function: 140,000 NAHB members: 32% are home builders/remodelers, 68% work in related fields: subcontracting, sales & marketing, financial services


North American Technician Excellence

Description: Nation’s largest non-profit certification organization for heating, ventilation, air conditioning and refrigeration technicians


National Comfort Institute

Description: Organization that provides heating, air conditioning, plumbing and electrical contractors with a focused offering of services and tools to help them improve their businesses


Non-Energy Benefits

Description: Secondary benefits from EE upgrades

Function: Support EE as having more value than dollars saved

Notes: Typically these are – Comfort, Health, Durability, Safety, IAQ, etc.


New England Clean Energy Council

Description: Voice of businesses building clean energy hub in Northeast USA; includes Northeast Clean Energy Council (nonprofit member organization), NECEC Institute (nonprofit for industry research, innovation, policy development, communications initiatives)


National Energy Education Development

Description: 1980 National Educational Program that currently encompasses a curriculum portfolio of 100+ teacher and student guides designed to engage and teach teachers and students about energy


Northeast Energy Efficiency Partnerships

Description: Non-profit founded in 1996 to accelerate energy efficiency in the Northeast and Mid-Atlantic states

Function: One of six Regional Energy Efficiency Organizations (REEOs) funded, in part, by US Department of Energy to support state efficiency policies and programs


Non-energy impact

Description: An additional benefit (positive or negative) for participants in energy efficiency beyond the energy savings gained from installing energy efficient measures


National Institute of Standards and Technology

Description: One of the nation’s oldest physical science laboratories, founded in 1901 and now part of the US Department of Commerce

Function: To promote US innovation, industrial competitiveness by advancing measurement science, standards, technology that enhance economic security, improve quality of life


National Resource Defense Coalition

Description: Works to safeguard the earth—its people, its plants and animals, and the natural systems on which all life depends

Function: Global coalition of 3,000,000 members and online activists with 700 scientists, lawyers, policy advocates working to ensure the rights of all people to the air, the water, and the wild


National Renewable Energy Laboratory

Description: National laboratory of the US Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy LLC

Function: Advances the science and engineering of energy efficiency, sustainable transportation, and renewable power technologies and provides the knowledge to integrate and optimize energy system


Net Zero Energy

Description: A building that balances its energy needs with energy produced from renewable, zero-emission sources



Description: A measurement of pressure

Function: Used by many building diagnostic tools

Notes: The pressure a pad of butter applies to a table. Metric equivalent of PSI


Pacific Gas & Electric

Description: Utility

Function: Natural Gas and Electricity

Notes: 1 of 4 CA – IOUs, Largest utility in the country


Peak Load Management Alliance

Description: Nonprofit organization founded in 1999 as the voice of load management practitioners

Function: Currently includes 155 member organizations: private & publicly owned utilities, technology companies, energy & energy solution providers, equipment manufacturers, research & academic organizations, consultants


Pacific Northwest National Laboratory

Description: Pacific Northwest National Laboratory is a leading center for scientific discovery in chemistry, data analytics, and Earth science, and for technological innovation in sustainable energy and national security.


Pressure Relief Valve

Description: Safety valve used to control or limit the pressure in a system

Function: Excessive pressure might otherwise build up and create a process upset, instrument or equipment failure, explosion, or fire


Pounds Per Square Inch

Description: A measurement of pressure

Function: Used to measure pressure

Notes: Measures the pressure per square inch in pounds


Photo Voltaics

Description: Solar panels that produce electricity

Function: Site generated power source

Notes: Can be used to supply all of the buildings energy needs – see ZNE


Resilient Electric Grid

Description: US Federal Energy Regulatory Commission (FERC) definition: Ability to withstand and reduce the magnitude and/or duration of disruptive events, which includes the capability to anticipate, absorb, adapt to, and/or rapidly recover from such an event


Regional Energy Network

Description: Network of local governments partnering to promote resource efficiency at the regional level, focusing on energy, water and greenhouse gas reduction

Function: Goal of a REN is to implement and administer energy efficiency programs the current IOUs cannot or do not have the available resources to implement within their service territory


Green Hydrogen

Description: Hydrogen generated by renewable energy or from low-carbon power

Function: Has significantly lower carbon emissions than grey hydrogen, produced by steam reforming of natural gas


Request For Info

Description: Common business process whose purpose is to collect written information about the capabilities of various suppliers

Function: Primarily used to gather comparative info to help make a next-step decision


Request for Proposal

Description: Document that solicits proposals from potential suppliers, often through a bidding process, by an agency or company interested in procurement of a commodity, service, or valuable asset


Regional Greenhouse Gas Initiative

Description: Cooperative effort among twelve Eastern states to reduce CO2 emissions from power plants within each participating state

Function: Market-based cap-and-invest initiative: within the RGGI states, regulated power plants must acquire one RGGI CO2 allowance for every short ton of CO2 they emit


Relative Humidity

Description: Ratio, expressed in percent, of the amount of atmospheric moisture present relative to the amount that would be present if the air were saturated


Southern California Edison

Description: Utility

Function: Electric only

Notes: 3 of 4 CA – IOUs


Southern California Gas Company

Description: Utility

Function: Natural Gas

Notes: 2 of 4 CA – IOUs, Owned by Sempura – Frequently referred to as So Cal Gas


San Diego Building Electrification Coalition

Description: Alliance of community, labor, business, faith, justice, environmental organizations working to advance electrification in residential and commercial buildings


San Diego Gas and Electric

Description: Utility

Function: Natural Gas and Electricity

Notes: 4 of 4 CA – IOUs, Owned by Sempura


DOE’s Solar Energy Technologies Office

Description: An Office of the US Department of Energy working to build a clean energy economy that benefits all Americans

Function: Eleven technology offices work toward the mission: Advanced Manufacturing, Bioenergy, Buildings, Hydrogen and Fuel Cells, Geothermal, Solar Energy, Vehicles, Water Power, Wind Energy, and the Federal Energy Management and Weatherization and Intergovernmental programs.


Solar Renewable Energy Credit

Description: A form of US Renewable Energy Certificate or “Green tag”

Function: The additional income received from selling SRECs increases the economic value of a solar investment and assists with the financing of solar technology

Notes: In conjunction with state and federal incentives, solar system owners can recover their investment in solar by selling their SRECs through spot market sales or long-term sales


Total Energy Pathways

Description: NEEP


Time Of Use

Description: Electric rate structure

Function: Encourages reduced electricity use during peak periods to manage load on the grid

Notes: Rates go up during peak grid load, typically 4pm to 9pm


Total Resource Cost

Description: EE rebate program cost evaluation tool

Function: A formula used to determine the cost effectiveness of EE programs

Notes: A TRC of 1.0 = One dollar saved for every dollar spent on running the program


Total System Benefit

Description: EE – Considers other benefits of upgrades

Function: Used to value all of the savings from EE

Notes: Non-energy benefits and avoided costs from not using energy – Negawattts


Thermal Expansion Valve

Description: Component in vapor-compression refrigeration and air conditioning systems that controls the amount of refrigerant released into the evaporator

Function: Intended to regulate the superheat of the refrigerant that flows out of the evaporator to a steady value


Utility Distribution Company

Description: Electric utility or subsidiary of an electric utility that distributes electricity to customers


U.S. Green Building Council

Description: Committed to transforming how buildings are designed, constructed and operated through LEED, the green building system with more than 100,000 buildings participating today


Vermont Energy Investment Corporation

Description: Nonprofit organization, whose mission is to reduce the economic and environmental costs of energy use


Virtual Power Plants

Description: Cloud-based distributed power plant that aggregates the capacities of heterogeneous distributed energy resources

Function: For the purposes of enhancing power generation, trading or selling power on the electricity market, and demand side options for load reduction


Variable Refrigerant Flow

Description: A type of compressor used in heat pump and air conditioning systems

Function: Matches output to load

Notes: Much more efficient than single speed or two stage systems


Weatherization Assistance Program

Description: Program that enables low-income families to reduce their energy bills by making their homes more energy efficient

Function: Funds are used to improve the energy performance of dwellings families in need, using the most advanced technologies and testing procedures available in the housing industry


Zero Net Energy

Description: A term for a building that produces as much energy as it uses

Function: Increases resilience and does not rely on 3rd party energy sources

Notes: Many ZNE building are still connected to the grid to provide energy when the PV can’t meet all of the buildings needs