US eGRID electricity factors

The US EPA (Environmental Protection Agency) publishes the eGRID database (Emissions & Generation Resource Integrated Database) roughly every one or two years.

The eGRID is a comprehensive source of data from the EPA's Clean Air Markets Division on the environmental characteristics of almost all electric power generated in the United States. The data includes emissions, emission rates, generation, heat input, resource mix, and many other attributes. eGRID is typically used for greenhouse gas registries and inventories, carbon footprints, consumer information disclosure, emission inventories and standards, power market changes, and avoided emission estimates.

In IBM® ESG Suite, this factor set is being applied as the default electricity emission factor set for electricity consumption reported from the US (including Puerto Rico). This factor set applies to both Electricity Scope 2 and Scope 3 (for reporting of electricity consumption not directly under operational control) consumption data. The indirect adjustment factors for transmission and distribution losses are included since factor year 2021.

Envizi ESG Suite has managed this factor set since 2008. There is no fixed date for the factor set publishing. In the past, it has followed a rough time interval of every two years, usually published in the first quarter of a year. Since 2020 the schedule has been adjusted to once a year.

Envizi ESG Suite in general loads the latest eGRID factors into the Envizi ESG Suite platform as soon as it is published by the US EPA. This factor set is a free resource that is openly available on the US EPA website.

Table 1. US eGRID electricity factors
Element Description
Website United States Environmental Protection Agency - Emissions & Generation Resource Integrated Database (eGRID)
Upcoming publication date Publishes annually in the first quarter of a year. Upcoming publication date: Jan 2025
Geographical coverage By default factors are applied to both Electricity Scope 2 and Scope 3 (location based factors) consumption data for US only (including Puerto Rico)
Data type coverage

Scope 2: electricity and electricity green offset

Scope 3: electricity

Effective and published dates

Effective dates always start with the first month of a calendar year and end with the last month of a calendar year. For example,Effective from = Jan-2016 and Effective to = Dec-2017.

Published dates are aligned when the factor set is published and available on the US EPA website, and the time when a new factor set is published. For example, one of the existing batches has Publish from = Mar-2021 and Publish to = Jan-2022.

For more information on effective and published dates see this article.

If you require a custom period for your factors, this will need to be managed through custom factors.

Global Warming Potential (GWP) Factors with an effective date later than 2012 use GWP defined by 2007 IPCC AR4 (N2O GWP = 298, CH4 GWP = 25) for equivalent CO2 amount calculations.

Factors with an effective date later than 2022 (publish date 2024) use GWP defined by 2014 IPCC AR5 (N2O GWP = 265, CH4 GWP = 28) for equivalent CO2 amount calculations.

Indirect CO2e Indirect factors associated with electricity transmission and distribution line loss is calculated as Total CO2e * Grid Gross Loss % / (1 - Grid Gross Loss %), with factors associated with eGRID regions using eGRID region specific GGL values, and factors associated with US state regions using the US average GGL value.

Indirect factor calculation methodology is adopted from the annual EPA documentation - eGRID Technical Guide.

Indirect CO2e factor values are a relatively new addition to the factor set since year 2023. Indirect factor values are back filled three years to cover eGRID factors from year 2021 to year 2023.

Managed publications and effective periods

Table 2. Managed publications and effective periods
Factor source reference Effective from Effective to Published from Published to
eGRID (Year 2005 Data). URL: https://www.epa.gov/egrid Original file name eGRID2005_aggregation.xls, tab name: SRL05.GWP and ST05.GWP   31/12/2006   30/4/2010
eGRID (Year 2007 Data). URL: https://www.epa.gov/egrid Original file name eGRID2010V1_1_year07_AGGREGATION.xls, tab name: ST07.GWP and SRL07 1/1/2007 31/12/2008 1/5/2011 31/3/2012
eGRID (Year 2009 Data). URL: https://www.epa.gov/egrid Original file name eGRID2012V1_0_year09_DATA.xls, tab name: ST09 and SRL09. 1/1/2009 31/12/2009 1/4/2012 31/1/2014
eGRID 9th Edition V 1.0 (Year 2010 Data). URL: https://www.epa.gov/egrid Original file name eGRID2010_Data.xls, tab name: SRL10 and ST10. 1/1/2010 31/12/2011 1/2/2014 30/9/2015
eGRID 2012 File (Year 2012 Data). URL: https://www.epa.gov/egrid Original file name eGRID2012_Data.xls, tab name: SRL12 and ST12. 1/1/2012 31/12/2013 1/10/2015 28/2/2017
Year 2014 data. Revised Release (v2): 2/27/2017 Original file name eGRID2014Data_v2.xls, tab name: SRL14 and ST14. Source: https://www.epa.gov/egrid 1/1/2014 31/12/2015 1/3/2017 28/2/2018
Year 2016 data, published 2/15/2018. Original file name eGRID2016_summarytables.xls, tab name: Table 1 and ST16. Source: https://www.epa.gov/egrid 1/1/2016 31/12/2017 1/3/2018 31/1/2020
Year 2018 data, published 1/28/2020. Original file name: eGRID2018_summary_tables.xls, tab name: Table 1 and Table 3. Source: https://www.epa.gov/egrid 1/1/2018 31/12/2018 1/2/2020 28/2/2021
Year 2019 Data: 2/23/2021.Original file name: eGrid2019_summary_tables.xls, tab name: Table 1 and Table 3. Source: https://www.epa.gov/egrid 1/1/2019 31/12/2019 1/3/2021 31/1/2022
Year 2020 Data: 1/27/2022.Original file name: eGrid2020_summary_tables.xls, tab name: Table 1 and Table 3. Source: https://www.epa.gov/egrid 1/1/2020 31/12/2020 1/2/2022 31/1/2023
Year 2021 Data: 1/30/2023.Original file name: eGrid2021_summary_tables.xlsx, tab name: Table 1 and Table 3. Source: https://www.epa.gov/egrid 1/1/2021 31/12/2021 1/2/2023 31/1/2014
Year 2022 Data: 1/30/2024.Original file name: eGrid2022_summary_tables.xlsx, tab name: Table 1 and Table 3. Source: https://www.epa.gov/egrid 1/1/2022   1/2/2024