You are here:

Green-e Glossary

This document is intended to help explain and define terms used in Green-e® governing documents. It functions as Green-e® Energy Appendix I, Green-e® Climate Appendix I, and Green-e® Marketplace Appendix E. A separate Appendix F: Green-e® Renewable Fuels Glossary is available here.

An abbreviated version of this glossary is also available in Chinese.

Last updated December 12, 2022.


A criterion applied to greenhouse gas (GHG) projects stipulating that project-based GHG reductions may only be quantified if the project or project activity "would not have happened anyway," i.e. that the project or project activity (or the same technologies or practices it employs) would not have been implemented in the baseline or status quo scenario and/or that project activity emissions are lower than baseline emissions. For more information on additionality requirements of Green-e® Climate, see the Green-e® Climate Standard.

Additionality Tests

Methods for the determination or demonstration of additionality. See Section 5.1.c(g) of the Green-e® Climate Standard for combinations of additionality tests required by Green-e®.

Agreed Upon Procedures Report

The report supplied to CRS prepared by the Auditor detailing the results of the annual verification audit by performing the procedures stipulated in the Annual Verification Audit Protocol. The Green-e® Climate program and the Green-e® Energy program have separate audit procedures and protocol.

Approved Registry

A carbon offset project registry that has been approved by Green-e®. Also see "Carbon Offset Project Registry."


An independent public accountant or certified internal auditor that performs the Green-e® Verification Audit and reports on agreed-upon procedures.

Auditor Attestation

An attestation to be completed by the Auditor signing the Agreed-Upon Procedures Report, which states that the Auditor has followed certain practices when reviewing Participant's verification materials and preparing the Agreed-Upon Procedures Report. It is available as an appendix of the Verification Audit Protocol.

Automatic Recurring Purchases

Purchases of Certified Offsets continuously over time through automatic renewals of a purchasing agreement or sustained enrollment in a purchasing plan.

Biological Carbon Sequestration

The uptake and storage of CO2 by plants and organisms.

Biological Carbon Stocks

The carbon contained in identified forest biomass categories, such as above and below ground biomass, at a specific point in time.

Bundled Carbon Offset Products

Certified carbon offsets may be sold bundled with other products and services, such as natural gas, for example.


A baseline or status quo scenario.

California Greenhouse Gas Cap-and-Trade Program

As one of the strategies to meet California's Global Warming Solutions Act (AB32), California has implemented a cap-and-trade program for greenhouse gas emissions arising from the electricity sector and other sources, commencing January 1, 2012. See Appendix A.5 of the Green-e® Renewable Energy Standard for Canada and the United States for more information and the resulting Green-e® Energy policy.

Carbon Dioxide Equivalent (CO2e)

The common unit of measurement for Greenhouse Gases that reflects the different Global Warming Potential of different greenhouse gases.

Carbon Offset

A reduction of greenhouse gases measured in tons of carbon dioxide avoided, sequestered or destroyed. Also see "GHG Emissions Reduction Credit."

Carbon Offset Content Label

A disclosure document showing the emissions reduction project type, project location, Endorsed Program, and proportions in a standardized form. Green-e® Climate requires all participants making Fixed and Customized Mix Sales of carbon offsets to provide their customers with a Carbon Offset Content Label. Participants making sales by project must provide their customers with project-specific information.

Carbon Offset Customized Mix

A carbon offset option in which the buyer can choose the proportions of different combinations of the project type, project location, and Endorsed Program.

Carbon Offset Fixed Mix

A carbon offset option in which the proportions of different combinations of project type, project location and Endorsed Program are fixed.

Carbon Offset Project

A single activity or combined program of activities that reduces, avoids, or sequesters Greenhouse Gas emissions beyond a baseline or business-as-usual scenario and at which measurement, reporting, and verification of emissions reductions can occur.

Carbon Offset Project Baseline Emissions

An estimate of GHG emissions, removals, or storage associated with a baseline scenario.

Carbon Offset Project Baseline Scenario

The scenario or emissions that would most likely have occurred in the absence of the carbon offset project or emission reduction activity.

Carbon Offset Project Crediting Period

The time period over which baseline emission estimates, derived from a baseline scenario or performance standard, are considered valid for the purpose of quantifying GHG emissions reductions. Once the crediting period for the baseline scenario expires, either no further GHG emissions reductions are recognized for the project or project activity, or a new (revised) baseline scenario or performance standard must be identified.

Carbon Offset Project Development Documents

Documents maintained by Carbon Offset Project Standards and Registries addressing a GHG emissions reduction project activity or program of activities that include a general project description, as well as validation, monitoring, and verification documentation and reports, and attestations and statements from project owners, developers, standards, and registries.

Carbon Offset Project List

The current list or portfolio of carbon offset projects being used by a Seller to supply carbon offsets. See the Green-e® Climate Code of Conduct for format and delivery requirements for Project Lists.

Carbon Offset Project Standard ("GHG Program")

A standard or program of standards that includes methodologies or protocols for carbon offset projects that specify technical, procedural, contractual and accounting requirements and qualifications. Can also refer to a program that oversees the validation of projects against methodologies or protocols, approves and registers validated projects, enforces monitoring of projects, and oversees the verification, crediting and issuance of GHG emission reduction credits for registered projects in accordance with program rules. See the Green-e® Climate Standard for requirements for Carbon Offset Project Standards and GHG Programs.

Carbon Offset Project Type

The type of project activity that reduces GHG emissions and supplies emissions reduction credits for a carbon offset. Examples of carbon offset project types include: renewable energy, energy efficiency, forestry, landfill methane capture, transportation, fuel switching, industrial gas destruction, and others.

Carbon Offset Project Validation

The assessment and approval of documents describing a project's conformance with project eligibility requirements of a GHG Program, including, as applicable, information on project design, the baseline scenarios, the demonstration of additionality, and an appropriate monitoring plan. Validation of a project or project activity typically occurs prior to the verification of GHG emissions reductions.

Carbon Offset Quality Criteria

The suite of internationally accepted criteria for carbon offsets that include: permanent, additional, verified, enforceable, and real.

Carbon Offset Registry

An electronic system for issuance, tracking, and retirement of GHG emission reduction credits.

Carbon Offset Sales by Project ("Project-specific sales")

A carbon offset option in which GHG emissions reductions from specific eligible projects are sold to customers based on their preference.

Center for Resource Solutions

CRS is a national nonprofit with global impact. It develops expert responses to climate change issues with the speed and effectiveness necessary to provide real-time solutions. Its leadership through collaboration and environmental innovation builds policies and consumer-protection mechanisms in renewable energy, greenhouse gas reductions, and energy efficiency that foster healthy and sustained growth in national and international markets. Administrator of the Green-e® certification programs.


The independent verification and provision of quality assurances for a product or service relative to a standard or set of requirements.

Certified Offset

A carbon offset sold as Green-e® Climate Certified. Green-e® Climate will certify carbon offsets sold by project or in mixes of project type, location, and Endorsed Program. A Certified Offset is a GHG emissions reduction that has been certified and issued by an eligible Endorsed Program under an eligible protocol or methodology, and the sale and marketing of which meets the requirements of this Code of Conduct, and the exclusive and correct delivery of which has been verified in accordance with the Green-e® Climate Code of Conduct and the Green-e® Climate Verification Audit Protocol.

Community Renewables Facility

Generally, Green-e® relies on State definitions of community renewables programs and facilities, issued by the Department of Energy, the Department of the Environment, Public Utilities Commission, municipal government or other government agency where the projects exist. Usually community renewables are in close geographic proximity to the customer, such as in the same city or county. At a minimum, community renewables should be within the electric service territory or within the same state as the customer, and the renewable output should be sold to the customer on a generation facility-specific basis, typically as a share of total output or capacity. Community renewables are typically smaller generation units, commonly less than 3MW.

Community Renewables Program

Generally, Green-e® relies on State definitions of community renewables programs and facilities, issued by the Department of Energy, the Department of the Environment, Public Utilities Commission, municipal government or other government agency where the projects exist. Such programs are supplied by community renewables facilities.


When two or more fuels are used in a single generator together to generate electricity. For Green-e® Energy, co-firing comes into play when an eligible fuel type is used together with an ineligible fuel, requiring calculations to show how much electricity was derived from the eligible fuel. Co-firing facilities must be pre-approved by Green-e® Energy before they may be used to supply certified sales. See Section II.B of the Green-e® Renewable Energy Standard for Canada and the United States.

Competitive Electricity Supplier

Also known as an electric service provider (ESP) or power marketer, a competitive power supplier sells electricity in the retail market.

Compliance Market for Renewable Energy

The Compliance Market refers to the purchase of renewable energy in order to comply with a specific law or mandate. The compliance market is primarily comprised of sales made to meet Renewable Portfolio Standards (RPS) requirements that many states have implemented. Also see "Renewable Portfolio Standard."

Content Label

Much like a nutrition label, the content label includes critical information about the composition of the product being purchased that Green-e® has identified as necessary for a customer to make an informed decision. (For renewable energy products see "Product Content Label." For sales of carbon offset see "Carbon Offset Content Label".)


The process of the review of a verification report and subsequent approval under Green-e® Climate that Certified Offsets offered by a participating Seller meet all program requirements as specified in this and related Green-e® Climate documents.

Default Electricity Mix (or "System Mix")

The mix of energy resource types used to generate the electricity that a customer is allocated by their electric service provider, if the customer does not purchase renewable energy.

Deregulated Utility Markets

Competitive markets (including electricity and gas) where consumers have a choice of which company they may purchase their electricity or gas from. The opposite of a regulated or monopoly market for these services.

Direct Purchaser

Purchasers who have achieved Green-e® certification for renewable energy or carbon offsets not purchased from sellers participating in the Green-e® Energy or Green-e® Climate programs.

Direct Purchasing

A purchase of Green-e® certified renewable energy or carbon offsets made directly from renewable energy generators and carbon offset projects, as an alternative to purchasing from a utility, competitive electricity provider, renewable energy certificate marketer, wholesale seller, or carbon offset provider/retailer participating in the Green-e® Energy and Green-e® Climate programs.

Distributed Generation

Small, modular, decentralized, grid-connected or off-grid energy systems located in or near the place where energy is used.

Double Claiming

A situation prohibited under Green-e® Climate in which more than one end-user claims the same GHG emissions reduction benefits.

Double Counting

A situation prohibited under Green-e® Climate in which the same GHG emissions reduction is counted more than once in any of the following: a GHG registry, towards a regulatory or voluntary GHG emissions reduction target, by an end user.

Double Issuance

A situation in which an attribute or benefit is credited or issued more than once or to more than one party at the time of issuance or along a transaction chain

Double Sale

A situation prohibited under Green-e® Climate in which the same GHG emissions reduction is sold to more than one party, resulting in a situation of double claiming or double counting.

Electric Utility

In a regulated electric market, the entity that owns and/or operates facilities for the generation, transmission, and/or distribution of electricity. In a deregulated market, this entity becomes an electric distribution company responsible for transmission and distribution only, and provides default electrical service to consumers that elect not to switch to an ESP.

Electricity Distribution and Transmission System

The system of power lines, poles, substations and transformers, directly connected to homes and businesses. The distribution company is the electric utility that delivers electricity to homes or businesses over these wires. The utility reads meters, maintains local wires and poles and restores power in the event of an outage.

Electricity Grid

The grid is a term used to describe the network of wires and cables which transport electricity from power plants to end users.

Eligible Emissions Reduction Credits

Greenhouse gas emissions reductions or credits that are eligible to supply a Green-e® certified carbon offset. Emissions reductions that have been credited and issued by an Endorsed Program and that are derived from a carbon offset project that falls within an eligible project type category for that Endorsed Program and is not excluded due to eligibility restrictions for that Endorsed Program (as specified in the Green-e® Climate Code of Conduct).

Eligible Renewable Resource

As defined in the Green-e®​ Renewable Energy Standard for Canada and the United States

Emissions Allowance (or Emissions Permit)

A legal documentation of the right to emit a specific quantity of a pollutant, for example GHGs under a GHG Cap-and-trade Program. Emissions Allowances can be transacted and potentially sold in the voluntary market where retirement of the allowance by or on behalf of a voluntary buyer eliminates the right to emit the quantified amount within the designated Cap-and-trade Program and results in a real overall reduction of emissions within the capped sector or region (see Regulatory GHG Cap-and-trade Emission Allowance Program and Voluntary GHG Cap-and-trade Emission Allowance Program). See the Green-e® Climate Standard for requirements for Emission Allowance Programs.

Emissions Allowance Program

A regulatory or voluntary program that issues Emissions Allowances, for example, a cap-and-trade program.

Emissions Categories (Scopes)

See World Resources Institute for definition

Endorsed Program

A GHG Project Certification Program or Standard identified by stakeholders and the Green-e® Governance Board as meeting the requirements set forth in the Green-e® Climate Standard and related documents, and which has been endorsed by the Board as an eligible source of reductions (supply) under the Green-e® Climate Program.


Applies to the issuance, ownership and transfer of emissions reduction credits, certificates, benefits or attributes (for example, emissions reduction credits or RECs) and indicates that issuance and ownership of benefits and attributes are backed by contracts or legal instruments that define their creation and ensure exclusive ownership.

Facility Online Date

The date a generator or generating facility was placed into service.

Fossil Fuel Resources

Conventional electricity generation using natural gas, oil, coal, or petroleum coke or other petroleum based fuels.

Gas Offset Program or Product

A natural gas product in which the natural gas is “bundled” or sold along with carbon offsets in order to neutralize the GHG emissions associated with the combustion of the natural gas.


A facility that physically generates electricity. The term is also used here to denote the owner of such a facility.

Geothermal Energy

Natural heat and steam from within the earth that is captured to generate electric power. Geothermal energy can also be used for space heating or industrial steam.

GHG Emissions Reduction

A reduction, removal or permanent storage of GHGs produced by: (1) projects or project activities or programmes of activities that have been validated and registered according to the requirements of an Endorsed Program; or, (2) the retirement of one or more GHG emission allowances from an Endorsed Program. GHG emissions reductions must originate from projects, or from emission allowances, that meet the principles and criteria contained in the Green-e® Climate Standard. They must meet the requirements of real, verifiable, permanent and enforceable. They may not be claimed or registered by more than one end-user.

GHG Emissions Reduction Credit

An independently issued, certified, and enforceable instrument representing a unique, verified and permanent reduction, removal, or sequestration of a specified quantity of greenhouse gases that has occurred at additional and registered project activity or program of activities.

GHG Emissions Reduction Type

Any unique combination of project type, project location, and Endorsed Program from which the GHG emissions reductions are sourced.

GHG Project Certification Program (GHG Program

A program composed of requirements, a Program Administrator and related governance entities that provides oversight for the production, verification and certification of GHG emissions reductions according to: (1) procedural and technical standards for the validation, monitoring, and verification of GHG emissions reduction projects; (2) contractual standards for information disclosure and avoidance of double-issuance and double-sales of GHG emissions reductions; (3) accounting standards that specify consistent methods for quantifying baseline emissions and GHG reductions, and accounting for emissions leakage; and (4) eligibility criteria including project additionality and permanence (see “Endorsed Program”).

GHG Subcommittee

A subcommittee of the Green-e® Governance Board that provides guidance on matters related to GHGs and carbon offsets.

Global Climate Change

Changes in the climate due to an enhanced greenhouse effect and a resulting rise in global average temperature.

Green Pricing

Green pricing refers to an optional utility service that enables customers of traditional utilities to support a greater level of utility investment in renewable energy by paying a premium on their electric bill to cover any above-market costs of acquiring renewable energy resources.

Green-e® Climate

A program of the Center for Resource Solutions, a retail standard and third-party certification program for carbon offsets sold in the voluntary market. Visit for more information.

Green-e® Climate Annual Verification Audit Instructions (Instructions)

A Green-e® document that provides instructions for participating Sellers of Green-e® certified carbon offsets on how to report annual sales and complete other obligations for the annual Green-e® verification audit.

Green-e® Climate Annual Verification Submission (Annual Verification Submissions)

The suite of required materials, including the final Agreed-upon Procedures Report, required to be submitted annually to the Center for Resource Solutions as part of the requirements of Green-e® certification of carbon offsets.

Green-e® Climate Certified Carbon Offsets

Carbon offsets that have been certified by Green-e® to meet the Green-e® Climate Standard and include Eligible Emission Reduction Credits and/or retired Emissions Allowances, the sale and exclusive delivery of which have been independently verified, and the sale of which has met the marketing and customer disclosure requirements specified in the the Green-e® Climate Code of Conduct.

Green-e® Climate Code of Conduct

The Green-e® governing document containing program requirements for Sellers of Green-e® certified carbon offsets, including the ethical guidelines, certification categories, eligible supply, and disclosure and verification requirements.

Green-e® Climate Logo

The certification mark, registered and owned by the Center for Resource Solutions, representing a Certified Offset, conforming with and used in conformance with the requirements of this Code of Conduct.

Green-e® Climate Standard

The Green-e® governing document containing the principles and criteria for Carbon Offset Projects, Carbon Offset Project Standards, GHG Emission Reduction Credits, and Emission Allowance Programs.

Green-e® Energy

A program of the Center for Resource Solutions, a third-party certification program for renewable energy sold in the North American voluntary market. Visit for more information.

Green-e® Energy Annual Getting Started Guide ("Guide")

Provides instructions for Participants in Green-e® Energy on how to fill in the Green-e® Energy Verification Bulk Upload Worksheet and what materials to assemble for the Auditor to complete the Agreed-Upon Procedures Report.

Green-e® Energy Annual Verification Audit Protocol ("Protocol")

Provides instructions for the Auditor on the procedures to perform in order to verify a Participant's annual sales and supply of renewable energy and/or RECs.

Green-e® Energy Certified Product

A renewable electricity program or REC product that meets all requirements of the Green-e® Energy program and that is sold or transacted by an entity contractually allowed to do so by Center for Resource Solutions. The Green-e® Energy certifies three product types: REC products, electricity products sold in deregulated markets, and electricity product sold in regulated non-competitive markets.

Green-e® Energy Code of Conduct

A governing document for Green-e® Energy eligibility and certification, containing product disclosure requirements.

Green-e® Renewable Energy Standard for Canada and the United States

A governing document for Green-e® Energy eligibility and certification. It is available on the Green-e® Energy website at Green-e® Energy Documents.

Green-e®  Governance Board (The Board)

The independent, standard-setting body made up of a diverse group of industry experts and stakeholder representatives that provides oversight over the development of the Green-e® Renewable Energy Standard for Canada and the United States and the Green-e® Climate Standard, as well as guidance to Green-e® staff on other program requirements and areas of interest.

Green-e®​ Logo

This is a registered certification mark, owned by the Center for Resource Solutions. The logo represents that a renewable energy product or carbon offset option is certified, or that a purchaser of these products has met minimum Green-e® Marketplace usage requirements. (See definition of "Certification.") Only participants in the Green-e® programs and having contracts with the Center may use the logo. The logo must be used in the manner described in relevant Green-e® Program's Code of Conduct and/or the "Green-e® Logo Use Guidelines."

Green-e® Marketplace

A promotion and claims certification program for qualified renewable energy users, run by the nonprofit Center for Resource Solutions. Visit

Green-e® Verification Process

The Green-e® Verification Process is an annual process to determine that program participants are sourcing appropriate quality and quantity of RECs or Offsets to back up any marketing statements they may have made. It is composed of an initial unaudited process as well as and audited agreed upon procedures report, typically due June 1 of the year following the year of sale. The Green-e® Energy and Green-e® Climate programs have separate verification processes.

Greenhouse Gas (GHG)

Gases that trap heat in the atmosphere and are emitted through natural processes and human activities. Green-e® Climate addresses GHG emissions reductions that originate from any gas that has been determined by the Intergovernmental Panel on Climate Change (IPCC) to have a radiative forcing effect on the atmosphere, including but not necessarily limited to the six principal GHGs included in the Kyoto Protocol: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride (CO2, N2O, CH4, HFCs, PFCs and SF6).

Historical Product Content Label

A primary disclosure document required for all sales of Green-e® Energy certified renewable energy and REC products. This document contains information about the certified product, including the actual mix of resources sold to the customer, which is independently verified by Green-e®. The delivery and contents of the label is monitored by Green-e®.


A technology that produces electricity from moving water that turns a generator.


Independent entails an absence of a financial interest in entities directly involved in the production of GHG emissions reductions. A requirement for entities engaged in the development, verification and certification of GHG emissions reductions, as well as the administration of GHG Program requirements.

Kilowatt-Hour (kWh)

A standard unit of measurement of electricity use. See the definition of Megawatt-Hour.


An indirect and/or unanticipated change in GHG emissions or carbon stocks occurring outside of the project's accounting boundary as a result of the project.

Low Impact Hydropower Institute (LIHI)

A national non-profit organization dedicated to reducing the impacts of hydropower generation through the certification of hydropower projects that have avoided or reduced their environmental impacts pursuant to the Low Impact Hydropower Institute's criteria.

Marketing Compliance Review

A twice-annual evaluation of marketing, disclosure, and enrollment materials used for the Green-e® certified product against the requirements of the Code of Conduct.

Megawatt-Hour (MWh)

A one Megawatt electricity generation plant operating at full capacity for 1 hour will produce one Megawatt-Hour of electricity. One MWh is equivalent to 1,000 kWh or one million Watt-Hours. The typical unit of measurement for a REC is one MWh.

Multiple Mix product

This category of certification covers a product for which the Green-e® Energy participant may sell up to 100 different resource mixes (a fixed combination of resource types, proportion of each resource type, and generation location) to customers. A Multiple Mix product may only be sold to commercial or wholesale customers.

Multi-Year Purchase Agreement

A purchase agreement or contract for the purchase of Certified Offsets for more than a single year.

Municipal Utility

A municipal utility is a non-profit utility that is owned and operated by the community it serves. Whether or not a municipal utility is open to customer choice and competition is decided by the municipality's public officials.

New Date

The term "New Date" is defined to include any eligible renewable facility beginning operation or repowered after the dates indicated on the following table:

Year of Sale New Date
2020 2006
2021 2007
2022 2008
2023 2009
2024 2010
2025 2011


New Renewable Resource

A renewable electricity generating facility that meets the online date criteria in Section II.E of the Green-e® Renewable Energy Standard for Canada and the United States. In most cases, a facility's commercial online date must be within 15 calendar years of its output being sold in a Green-e® Energy certified renewable energy product.


Nuclear energy is not an eligible resource type under the Green-e® Renewable Energy Standard for Canada and the United States and cannot be used to supply certified sales.

Null Electricity (or Power)

The underlying power remaining when the RECs have been stripped off and sold elsewhere. Null power is not renewable but is the unspecified and undifferentiated power that has the attributes of the overall system mix or the residual mix where specified power purchases have been removed.

Offline Sales

Sales of Certified products not transacted via a web-based sales channel.

Offset Card

A pre-printed, single-denomination (uniform quantity and type of offsets) card (need not be in physical card form) used for in-person, over-the-counter offset transactions.

On-site renewable energy

Renewable energy that is consumed at the same location where it is produced. On-site generation is a form of distributed energy generation.

On-site Verification

Verification of carbon offset project or facility qualifications or of an activity, such as GHG emissions reductions or sequestration, via an in-person site visit by the verifier. Can be distinguished from a 'desk-top' review of documentation.

Online Sales

Sales of Certified products transacted via a web-based sales channel.


A term used to refer to companies with contracts with CRS to be in the Green-e® programs. Participants could be utilities, REC sellers, carbon offset sellers, brokers, generators and end-use buyers.


Applies to GHG emissions reductions and sequestration and the extent to which they last in perpetuity without the possibility of reversal.

Power Pool

An association of interconnected electric systems in a region, often having an agreement to coordinate operations and plans for reliability improvements.

Power Purchase Agreement

A contract for electricity.

Price, Terms & Conditions

A primary disclosure document required for all sales of Green-e® certified products. The Price, Terms & Conditions requirements are listed in the program's respective Code of Conduct. See "Green-e® Energy Code of Conduct" or "Green-e® Climate Code of Conduct."


The renewable electricity or REC that a Participant sells to customers.

Product Content Label (PCL)

A disclosure document showing the REC or renewable energy's generation type, proportions, and location in a standardized form. Green-e® requires all participants to provide their customers with a Product Content Label.

Project List

A Project List is a list of the projects from which Seller sourced Certified Offsets. For Fixed or Customized Mix certification and sales, the Project List must be posted on Seller’s website and meet the requirements provided in this document.

Prospective Product Content Label

A primary disclosure document required for all sales of Green-e® Energy certified renewable energy and REC products. This document contains information about the certified product, including the expected mix of resources to be sold to the customer. The delivery and contents of the label is monitored by Green-e®.

Qualifying Renewable Energy

Green-e® Energy Certified renewable energy products or onsite generation that meets the Green-e® Renewable Energy Standard for Canada and the United States.


The act of purchasing RECs or carbon offsets, and selling them to another party. The re-seller must be a Participant in Green-e® in order to re-sell a commodity as "certified."


Applies to GHG emission reductions and the extent to which they have been quantified in accordance with technically and scientifically sound accounting practices such that they represent actual emissions reductions beyond a baseline and are not artifacts of incomplete or technically flawed accounting.

REC Broker

A broker connects a buyer and seller of renewable energy, but does not purchase or take title to the renewable energy being traded.

REC Marketer

A REC marketer (seller) purchases renewable energy from a generator or a wholesale renewable energy provider, and then "markets" (sells) that energy to retail or wholesale customers who wish to buy a renewable energy product. A marketer takes title to the renewable energy and resells it, but at no time claims the environmental benefits of that renewable energy—only the final buyer can make those claims.

REC or Renewable Energy Aggregator

A REC aggregator purchases RECs from distributed generation and sells as an aggregated unit

Referenced Carbon Offset Project Standard

A Carbon Offset Project Standard that is referenced in another standard or by another program such that the project standard is maintained by an external organization.

Regional Greenhouse Gas Initiative (RGGI)

Nine states in the Northeast and Mid-Atlantic (Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New York, Rhode Island and Vermont) have agreed to take part in a regional cap-and-trade program for greenhouse gas emissions arising from the electricity section on those states, commencing January 1, 2009.


An electronic system for issuance, tracking, trading, and retirement of GHG emissions reductions and emissions reduction credits.

Renewable Energy

Electricity generated from resources that naturally replenish themselves over a period of time.

Renewable Energy Attributes

The physical characteristics and the environmental benefits of renewable electricity generation that are determined by those physical characteristics (such as facility size, location, and resource type).

Renewable Energy Certificate (REC)

A tradable, contractual instrument that represents the full suite of attributes of 1 Megawatt-hour of renewable energy generation on the electricity grid. RECs are the sole means to claim usage of grid-connected renewable electricity in the United States, and the compliance instrument for consumption- or delivery-based state Renewable Portfolio Standards. Renewable electricity generation and use are tracked through RECs, and so by matching RECs with your electricity service you are using renewable electricity. A REC represents the environmental benefits of 1 megawatt-hour of renewable electricity that can be paired with electricity.

Renewable Energy Tracking System

Renewable energy generation ownership can be accounted for in two different ways: through contract-path auditing and through tracking systems. Tracking systems are becoming the preferable method because they can be highly automated, contain specific information about each MWh, and are accessible over the internet to market participants. Tracking systems are databases, typically electronic, with basic information about each MWh of renewable power generated in the region. Electronic tracking systems allow RECs to be transferred among account holders much as in online banking. Renewable energy tracking systems assign a unique identification number for each megawatt hour of renewable electricity generated in a particular region. The database tracks certain information for each megawatt hour, including facility location, generation technology, facility owner, fuel type, nameplate capacity, the year the facility began operating, and the month/year the MWh was generated. Since each MWh has a unique identification number and can only be in one account at any time, this reduces ownership disputes.

A tracking system can be used by regulators as a registry of generating facilities, as a means of verifying compliance with a Renewable Portfolio Standard, for aiding in the creation of disclosure labels, and for other purposes such as verifying wholesale supply for green power products. Tracking systems are not substitutes for certification and verification, as tracking systems only monitor wholesale transactions—individual retail green power customers do not hold accounts on tracking systems. That is why certification such as Green-e® is so important for voluntary purchasers.

There are several regional tracking systems in operation in the U.S., and more under development. Fully operational tracking systems include the New England Generation Information System, ERCOT's Texas Renewables, WECC's Western Renewable Energy Generation Information System, the Midwest Renewable Energy Tracking System and PJM's Generation Attribute Tracking System. (see map, "Renewable Energy Tracking Systems in North America" as a PNG or PDF):

Tracking System Map

Renewable MWh

A term used to refer to RECs or renewable energy.

Renewable Portfolio Standard

A state or federal level policy that requires that a minimum amount (usually a percentage) of electricity supply provided by each supply company is to come from renewable energy. Green-e® Energy does not certify RECs that are counted toward a state RPS. Also see "Compliance Market."

Reporting Year

The year-long period over which sales of Green-e® certified renewable energy and carbon offsets are reported to CRS for verification. Historically, the reporting year has been the calendar year of sales or delivery. Specific Reporting Years are specified in Green-e® Verification materials.

Repowering / Repowered Facility

A generation facility that has replaced enough of it generation equipment to be equivalent to a brand new facility. To be eligible under the Green-e®  Renewable Energy Standard for Canada and the United States, a repowered facility must meet certain criteria, submit paperwork to Green-e® Energy, and be pre-approved before being used to supply Green-e® Energy certified sales. See Section II.E.2 of the Standard.


Retirement occurs when a GHG emissions reduction or credit is used by the owner of the GHG emissions reduction. Once a GHG emissions reduction is retired, it may not be sold, donated, or transferred to any other party. No party other than the owner may make claims associated with retired GHG emissions reduction.


See "Emissions Categories" above.

Service Area or Territory

The geographical territory served by an electric service provider.


As used in this document, Seller refers to the company that is selling Green-e® Climate Certified Offsets. Participating Sellers must adhere to disclosure, contractual and marketing requirements contained in Green-e® Climate documents.

Solar Power

Sources that use solar radiation to produce electricity. Photovoltaic technologies convert sunlight directly into electricity. Solar thermal electric facilities use the heat of the sun to generate electricity.

Single Mix product

This category of certification covers a product for which all customers of the product receive one unique resource mix (a fixed combination of resource types, proportion of each resource type, and generation location). A Single Mix product may be sold to any customer type (residential, commercial, or wholesale).

Specific Purchases

Electricity transactions which are traceable to specific generation sources by an auditable contract trail or equivalent, such as a tracking system, that provides commercial verification that the electricity source claimed has been sold once and only once to the Green-e® Participant.


Supply for RE Products is RECs or RECs and electricity, depending on the product. Supply for carbon offsets is GHG Emission Reduction Credits or retired Emission Allowances.

Third-party Distributor

A Third-party Distributor is a company that sells Certified Offsets without any direct relation to procurement of supply of GHG emissions reductions, but rather through an arrangement with Seller of Certified Offsets.

Tracking System

(see Renewable Energy Tracking System)


An exchange of ownership from one party to another party. This may occur in a registry account or in a tracking system

Unbundled Renewable Energy Certificates (unbundled RECs)

RECs that are sold, delivered, or purchased separately from electricity.

Utility Regulatory Authority

Any utility regulatory authority or governing board having jurisdiction over the allocation of costs from the electricity generating facility. For example, a state's Public Utilities Commission, or a Municipal Utility's Board.


The assessment and approval of documents describing a project’s conformance with project eligibility requirements of a Participating GHG Project Certification Program, including, as applicable, information on project design, the baseline scenarios, the demonstration of additionality, and an appropriate monitoring plan. Validation of a project or project activity typically occurs prior to the verification of GHG emissions reductions.


Annual process of checking supply matches sales of eligible resources and that customer expectations have been met.

Verification Submission Timeline and Deadlines

The Green-e® document that details the timeline, due dates associated with preparing and submitting Green-e® Verification Submissions for a given Reporting Year.


A requirement for GHG emissions reductions under this program; entails that it has been demonstrated that GHG emissions reductions have occurred at a project or programme of activities.

Verified Emission Reduction

Applies to GHG emissions reductions and sequestrations and the extent to which they have been independently substantiated and authenticated.

Verification Report

A report prepared by an independent third party entity, pursuant to a verification, which reports the findings of the verification process, including the quantity of GHG emissions reductions that have been found to have been generated.


The date or time period that a GHG emissions reduction occurred or REC/renewable electricity was generated.

Voluntary GHG Cap-and-trade Emission Allowance Program

A GHG reporting and trading system within which entities make a legally binding commitment to meet certain GHG emissions reduction targets. Such a system may include the allocation to entities of emission allowances that represent the right to emit a specific quantity of GHGs. Entities may trade emission allowances.

Voluntary Renewable Energy Market

The Voluntary Market refers to purchases of renewable energy that are made above and beyond the minimum amounts required by law.

Welcome Materials

Any materials distributed by Seller to the customer after the purchase of Certified Offsets.

Welcome Packet

The packet of materials that must be sent to customers of Green-e® Energy certified products within 60 days of enrollment. The packet must at a minimum include a welcome letter, the Prospective Product Content Label, and the Price, Terms, and Conditions.

Wholesale Customer

A company that buys renewable energy or carbon offsets from a Seller with the intention of reselling them to another wholesale or retail customer.

Wholesale Product

Renewable energy or carbon offsets sold to a customer that will resell the commodity. This is opposed to a retail customer who keeps or retires the commodity in order to make claims about purchase.

Wholesale Supplier

A company that sells renewable energy or carbon offsets to a company that intends to resell them.

Wind Energy

A renewable resource using wind to turn a turbine to generate electricity.