2025 Residual Mix Emissions Rates (2023 Data)

 

Released February 2, 2026

The information in this table can be used to calculate the greenhouse gas (GHG) emissions associated with untracked and unclaimed U.S.-based sources of electricity, based on location of consumption. The table provides the “Green-e® residual mix emissions rate,” an emissions rate that is adjusted to remove all Green-e® Energy certified sales for each Emissions & Generation Resource Integrated Database (eGRID) subregion1 (see eGrid subregion map).

Green-e® residual mix emissions rates are published each year using Green-e® Energy voluntary renewable energy market sales data collected during the annual Green-e® Energy verification audit from two calendar years prior and the most recent U.S. generation and emissions rate at the time of publication. It does not include any data that is not reported through the Green-e® Energy verification process. The residual mix emissions rate used should be based on the eGRID subregion in which the electricity is consumed. Individuals can figure out which eGRID subregion in which they are located by using the EPA’s Power Profiler tool.

Scope 2 Reporting

When calculating the emissions from unspecified purchased or acquired electricity (considered “Scope 2” emissions, as defined by the World Resources Institute [WRI]), where more-accurate information about the resources and emissions associated with electricity use is not available from the user’s state, region, or electricity supplier, residual mix emissions rates should be used. Regional residual mix emissions rates that factor out all specified electricity purchases are not yet available for all regions of the U.S. or published by a national data source. Until such time, Green-e® residual mixes are available, which factor out all Green-e® Energy certified sales of renewable energy. Users reporting their GHG data should cite the use of these residual mix rates in their accounting. Use of these numbers is compatible with WRI’s Greenhouse Gas Protocol Scope 2 Guidance,2 which defines residual mix in more detail. Green-e® Energy also offers the Green-e® Energy Summary of WRI Scope 2 Guidance, a guide for purchasers of Green-e® Energy certified renewable energy on how to calculate Scope 2 emissions.3

Residual Mix Rate Calculation Methodology

This table shows the residual mix calculation based on eGRID subregions. These rates were calculated using the data collected by Green-e® Energy during annual verification of 2025 certified sales and the 2025 emissions and generation data provided by eGRID in the U.S. for each eGRID subregion4.

The residual mix emissions rate is calculated by first subtracting all unique Green-e® Energy certified sales5 (in megawatt-hours [MWh]) from the total generation within each subregion. The total CO2 emissions for each region are then divided by this new generation number for each subregion, resulting in an adjusted emissions rate (lb CO2/MWh) that accounts for use of renewable energy from a Green-e® Energy certified product.

For this calculation, each U.S.-generated MWh is assigned to a specific eGRID subregion, with generating facilities assigned to eGRID subregions using facility zip codes and Energy Information Agency data. Generation from facilities that cannot be readily assigned to eGRID subregions is excluded from these residual mix emissions rates.

2025 Green-e® Residual Mix Emission Rates (2023 Data)

eGrid Subregion CO2 Emissions (tons) Net Generation (MWh) Emission Rate (lb / MWh) Voluntary RE emissions (lbs) Voluntary RE (MWh) (12-month vintage) Adjusted System Mix (lbs / MWh) (12-month vintage) Difference (lbs / MWh) (12-month vintage) % Difference (12-month vintage)
AKGD 2,306,612 5,096,873 905.109 0 53120 914.641358555 9.532 1.05%
AKMS 413,227 1,582,032 522.400 0 30672 532.7287750732 10.329 1.98%
AZNM 61,987,422 175,554,660 706.189 0 382857 707.7328762919 1.544 0.22%
CAMX 47,510,357 220,986,983 429.983 0 2155596 434.2188488632 4.236 0.99%
ERCT 175,736,550 477,137,386 736.629 0 50494590.72 823.8111701854 87.182 11.84%
FRCC 98,119,941 250,055,524 784.785 0 5134028.79 801.2358505462 16.451 2.10%
HIMS 1,479,863 2,611,613 1,133.294 0 0 1133.2941126422 0.000 0.00%
HIOA 4,906,807 6,547,005 1,498.947 0 0 1498.9471597657 0.000 0.00%
MROE 17,225,524 24,520,968 1,404.963 0 8139.43 1405.4293110571 0.466 0.03%
MROW 111,619,165 240,934,539 926.552 0 12646591 977.8804857694 51.328 5.54%
NEWE 27,896,766 102,716,863 543.178 0 10212 543.2319201588 0.054 0.01%
NWPP 85,523,767 269,253,053 635.267 0 8722197.738 656.5346458848 21.268 3.35%
NYCW 14,978,350 34,602,268 865.744 0 0 865.7438473693 -0.000 -0.00%
NYLI 5,841,684 9,823,462 1,189.333 0 0 1189.3331495914 0.000 0.00%
NYUP 10,352,339 85,283,183 242.776 0 8465 242.799711895 0.024 0.01%
PRMS 13,550,534 17,501,153 1,548.530 0 0 1548.5304197432 0.000 0.00%
RFCE 85,344,050 284,874,109 599.170 0 32026 599.237652084 0.068 0.01%
RFCM 44,714,189 91,629,482 975.978 0 1175126 988.6575128178 12.680 1.30%
RFCW 240,167,462 524,352,082 916.054 0 988102.721 917.7836884236 1.730 0.19%
RMPA 35,276,810 67,674,810 1,042.539 0 1480878.99 1065.862365519 23.323 2.24%
SPNO 31,871,638 73,458,953 867.740 0 10770053.51 1016.8191819725 149.079 17.18%
SPSO 69,202,640 158,074,960 875.567 0 22485946.44 1020.7706100978 145.204 16.58%
SRMV 65,406,384 176,359,170 741.741 0 761511 744.9573566218 3.216 0.43%
SRMW 65,795,246 105,391,939 1,248.582 0 3215049 1287.869422947 39.287 3.15%
SRSO 108,350,077 256,144,699 846.007 0 2724815 855.1031962619 9.096 1.08%
SRTV 94,541,910 209,324,308 903.306 0 96019 903.7201505099 0.414 0.05%
SRVC 95,256,781 319,478,861 596.326 0 2952681 601.8887958252 5.563 0.93%

1 eGRID subregions are identified and defined by EPA and were developed as a compromise between NERC regions (which EPA felt were too big) and balancing authorities (which EPA felt were generally too small). Using NERC regions and balancing authorities as a guide, the subregions were defined to limit the import and export of electricity in order to establish an aggregated area where the determined emission rates most accurately matched the generation and emissions from the plants within that subregion.

2 Available at www.wri.org/research/ghg-protocol-scope-2-guidance.

3 The Green-e® Energy Summary of WRI Scope 2 Guidance is available at Green-e® Scope 2 Summary

4 U.S. EPA’s Emissions & Generation Resource Integrated Database (eGRID). eGRID2023 (released January 15, 2025) contains the complete release of year 2023 data, at https://www.epa.gov/egrid/data-explorer.

5 Unique Green-e® Energy certified sales remove any MWh associated with a Green-e® Energy certified retail sale for which the supply was purchased via a Green-e® Energy certified wholesale transaction, since these two sales represent the same MWh of generation.