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Frequently Asked Questions (FAQ)

This page provides answers to common questions asked by consumers and participants in the Green-e® certification program.


Why is Green-e® Energy certification important?

Green-e® Energy is a consumer protection program designed to provide purchasers of renewable energy good product information, assurance of product quality and verification of product ownership.


What renewable energy sources are eligible under Green-e® Energy?

Wind, Solar, Geothermal, certain Hydroelectric and certain Biomass electricity-generation technologies can be used in a Green-e® Energy Certified renewable energy product. Facilities producing electricity from these sources need to have been built within 15 years of the year customer purhcases the renewable energy. For further specifications on eligibility of resource and facility types and online dates, please see the Green-e Renewable Energy Standard for Canada and the United States.


How can I talk about the carbon value associated with my Green-e® Energy Certified purchase?

Carbon value” refers to claims about the number of tons of carbon dioxide that a renewable energy purchaser would have consumed if they had purchased regular electricity instead of buying renewable electricity or RECs.  Purchasing renewables lowers the purchaser’s carbon footprint, but may not reduce global carbon emissions.  The carbon equivalency of renewable energy use is often expressed as the number of trees planted or cars taken off the road that is equivalent to the emissions the purchase would otherwise have been responsible for. Please refer to the Green-e Energy Code of Conduct and see Section VII.B. for Green-e® Energy rules around carbon equivalency claims. If you are participating in Green-e Marketplace, see that program's rules as well. In addition, the U.S. Environmental Protection Agency hosts a Greenhouse Gas Equivalencies Calculator.


What is the difference between Green-e® Energy Certified and Green-e® Energy Eligible?

When a renewable energy product is sold as Green-e® Energy Certified, it means that seller has a contract with Green-e® Energy and agrees to abide by all Green-e® Energy rules. The seller must undergo annual verification of its renewable energy supply and sales, and the product offered was generated by resources that are eligible under the Green-e® Renewable Energy Standard for Canada and the United States.

When renewable energy is represented as Green-e® Energy certifiable, it means that in the seller's opinion the renewable energy they are selling meets the eligibility criteria in the Green-e® Renewable Energy Standard for Canada and the United States. However, Green-e® Energy certifiable does not mean that the seller has a contract with Green-e® Energy, or that Green-e® Energy has any insight into the seller's sales. Green-e® does not support the use of the term Green-e® Energy "certifiable" or "eligible," which both imply certification.

The term "Green-e® Energy Eligible" also shows up in renewable energy tracking systems, and refers to the eligibility of a generation facility itself, not its RECs. Generation facilities that are registered in any of the tracking systems in the U.S. are able to have a check box in the facilities' profiles indicating that the facilities meet the eligibility criteria in the Green-e® Renewable Energy Standard for Canada and the United States checked (except ERCOT, which does not have such a box). Before this box is checked, a facility must submit a form to Green-e® Energy for approval, and only if the form is accepted and accurately reflects eligibility under the Standard does the "Green-e® Energy Eligible" box get checked. All facilities that have submitted an approved Tracking Attestation (including such facilities in ERCOT) are listed on Green-e Energy Tracking Attestations Received (password required). The output of a facility with this box checked may be used in Green-e® Energy Certified sales, but the seller must still have an active contract with Green-e® Energy in order for the sale to be certified.

For wholesale purchases made by existing participants in the Green-e® Energy program, it is always best to be clear about whether the REC is eligible for use in a Green-e® Energy certified sale or the facility has been approved as meeting the facility-level criteria in the Standard.

For all other buyers, because there are many facets to eligibility, the only way to be assured that renewable energy that you buy does meet all applicable criteria in the Standard is to buy Green-e® Energy certified. A list of sellers able to offer a Green-e® Energy certified product can be found at

To learn more, see Green-e "Certifiable" is NOT Green-e Certified [PDF]


Can Green-e® certified RECs/renewable energy generated in the United States be used for a valid renewable energy usage claim in Canada, and vice-versa?

Yes. Green-e® does not limit the ability of buyers to use RECs and renewable energy to match renewable energy usage and substantiate Scope 2 (purchased electricity) claims, as in this example.

In general, U.S. and Canadian RECs are fungible, consistent with guidance for making credible renewable electricity usage claims as well as valid Scope 2 emissions claims within defined market boundaries (for example, see Making Credible Renewable Electricity Usage Claims and GHG Protocol Scope 2 Guidance). Market boundaries for renewable energy usage and Scope 2 claims are partially—but not entirely—determined by physical grid interconnection or consistent regulatory frameworks. Other factors that affect market boundaries can include governmental recognition, market participation, and regional standards.

With respect to Canada and the U.S., there are shared physical grid interconnections and compatible regulatory and legal frameworks, as well as a long history of attribute transactions, mutual recognition of REC instruments, and independent standards that treat these separate countries as part of the same energy attribute market.


Does Green-e® have current pricing information for RECs?

Pricing is not a criterion for Green-e® Energy certification of a renewable energy option, and so Green-e® Energy does not have information on renewable energy pricing across the market. However, all sellers of Green-e® Energy Certified renewable energy products must provide pricing information to potential customers as part of their Price, Terms, and Conditions disclosure requirements.


How does Green-e® Energy count for the US Green Building Council's LEED points?

Under current Leadership in Energy and Environmental Design (LEED) green building standards developed by the U.S. Green Building Council, points are awarded under the Green Power credit for purchases of RECs or renewable electricity that are Green-e® Energy Certified or equivalent. The require purchase size ranges from 35–50% of the building's electricity usage for two years. For more in depth LEED questions please contact the US Green Building Council.


Does my purchase of a Green-e® Energy Certified product allow me the use of the Green-e® logo on my website or printed marketing materials?

Not by default. While purchasers of certified renewable energy may talk truthfully about their purchases, Green-e® logo use is restricted to those participating in Green-e® Marketplace, a logo-licensing program for commercial customers that wish to use the Green-e® logo in association with their purchase. For more information about the program please see the Green-e Marketplace portion of this Web site. In some cases residential purchasers are allowed to display the logo in association with their purchase, though only through approved materials offered by their renewable energy provider.


When do RECs expire?

Green-e® Energy Certified sales that are made in a given calendar year must be generated within the 12 months of that calendar year, the six months before the calendar year began, or the three months after the calendar year has ended. This creates a 21-month window of eligible generation dates from which renewable energy generation can be used toward Green-e® Energy Certified sales in any given calendar year.

Outside of Green-e® Energy, each program with rules about RECs will have its own range of generation dates that is acceptable. For example, some state Renewable Portfolio Standards (RPSs) require the use of renewables generated in the year they are to be counted toward the RPS, while others have no vintage rules at all and allow a REC to be used toward a year's requirements regardless of how long ago it was generated. Be sure to consult the rules of the programs you wish to comply with before making sales or purchases for that program, since there is not a universal set of rules for REC expiration.


I generate my own renewable electricity. Do I need to sign up with Green-e® Energy and certify my sales?

Green-e® Energy is a voluntary program. It is set up to protect retail purchasers of renewable energy in the voluntary market, and the most value that Green-e® Energy provides is oversight of the sale of renewable energy to retail customers.

Oftentimes a generator will choose not to sell its renewables directly to a retail customer, but instead sell to an entity that will re-sell the renewables in a wholesale transaction. Green-e® Energy certification of such a wholesale transaction is possible, but not necessary for Green-e® Energy to provide its consumer protection role.

The decision to sign up for Green-e® Energy should be based on the types of sales you will make as a generator, the cost of signing up with Green-e® Energy, your ability to comply with the Green-e® Renewable Energy Standard for Canada and the United States and Green-e® Energy Code of Conduct, and the needs of your potential customer.

If a generator sells renewables wholesale to a re-seller, that re-seller might sell those renewables in a Green-e® Energy Certified transaction at a later date. This is possible so long as the re-seller has a contract with Green-e® Energy to make certified transactions. In this case, the re-seller will need documentation from the generator in order for the re-seller to comply with Green-e® Energy verification rules. This document is called a Generator Attestation, and can be found at Green-e Energy Documents, along with other verification materials. Generators filling out a Generator Attestation should also read the Green-e® Renewable Energy Standard for Canada and the United States to ensure that they are able to sign the Generator Attestation.


What is the difference between a Competitive Electricity Supplier's renewable electricity program and a Utility green pricing program?

A competitive electricity product is renewable electricity sold by an electric service provider in a deregulated state, one that allows for competition among electricity providers. In regulated states, electric utilities are not subject to competition and may offer a certified green pricing program. Green-e® Energy has rules specific to electric service providers in these different types of states; see the Green-e Renewable Energy Standard for Canada and the United States. and the Code of Conduct for details.


What is the difference between a Single Mix and a Multiple Mix product in Green-e® Energy?

Please see How to Join of Section V of the Green-e Energy Code of Conduct for details of Green-e® Energy contract types.


I am selling a Green-e® Energy Certified product. Do I need to buy a certified product to supply my certified sales?

No. In order for you to be able to count renewable energy towards your Green-e® Energy Certified sales, you must be able to show documentation tracing the chain of custody of a renewable MWh back to the generator, as well as show that the renewable MWh meets all applicable criteria in the Green-e Renewable Energy Standard for Canada and the United States. The chain of custody and characteristics of the renewable MWh are checked during the annual verification process that all sellers participating in Green-e® Energy must undergo, regardless of whether you bought a Green-e® Energy Certified product to supply your certified sales. Buying certified supply is possible, but not required.