United States

EPA GHG Emission Factors Hub and eGRID

The US reference for corporate inventories: per-gas fuel factors, the eGRID electricity subregions, and six years of back catalogue.

Overview

The Emission Factors Hub is a single workbook EPA republishes every January. Tables 1–5 cover stationary and mobile combustion, Table 7 purchased steam, Tables 8 and 10 business travel and freight, Table 9 waste, and Tables 11–12 the GWPs EPA used.

Unlike DEFRA, EPA publishes raw gas masses: kilograms of CO₂, and grams of CH₄ and N₂O, often on the same row. Slate converts the grams once at import and then applies your organisation's chosen GWP set, so the same EPA factor can be reported under AR5 or AR6.

Grid electricity does not come from the Hub's Table 6. It comes from eGRID directly, because EPA revises eGRID after the Hub goes to press. eGRID2023 rev 2 (June 2025) moved New York City by −11.3% against the figure the Hub printed in January.

At a glance

Publisher

U.S. Environmental Protection Agency, Center for Corporate Climate Leadership

Code in Slate

US_EPA

Covers

Fuels, US grid electricity by subregion, steam, travel, freight and waste

Publishing schedule

Hub annually each January, with eGRID alongside. Check for a later eGRID revision before every import.

Licence

U.S. Government work (public domain)

Bulk download

Permitted by the licence, from the publisher

Official files

These go straight to the publisher, never to a copy hosted by Slate. Where a page holds several files, the note names the exact one Slate imports.

• Data fileghg-emission-factors-hub-2025.xlsx

  Published 15 Jan 2025. The workbook Slate imports for 2025. 2020–2024 are imported from their own year's workbook.

  Get file↗

• Referenceghg-emission-factors-hub-2025.pdf

  Published 15 Jan 2025. The same tables as a citable PDF.

  Open↗

• Data fileeGRID2023 summary tables, rev 2

  Published 12 Jun 2025. Source of every US subregion electricity factor in Slate.

  Get file↗

• Data fileeGRID2023 data file, rev 2

  Published 12 Jun 2025.

  Get file↗

• MethodologyeGRID2023 technical guide

  Published Jan 2025.

  Open↗

• GuidanceStationary combustion guidance

  Published Dec 2020.

  Open↗

• GuidanceEmission factors for waste vs WARM

  Published Apr 2020. EPA's own explanation of why Hub Table 9 and WARM must never be added together.

  Open↗

Releases in Slate

A release is one immutable published edition. Slate keeps the publisher's file unmodified, records its checksum, and selects a release by the date of each activity, so a 2022 record is always priced on 2022 data.

What Slate uses it for

How Slate handles it

The decisions that change numbers, and why they were made the way they were.

1. 01

   Table 9 is a separate edition

   Alone among the Hub's tables, the waste factors are already CO₂e and on AR4. Sharing a release with the per-gas tables would double-apply GWPs to some rows and not others, so they are imported as edition hub-waste.

2. 02

   One date, one release

   Each historical Hub is bounded to its own year and only 2025 is open-ended, so a transaction date selects exactly one release. Recalculating a 2022 record uses the 2022 Hub.

3. 03

   eGRID only on the current year

   Older Hubs shipped with their own eGRID editions, which Slate doesn't hold. Attaching eGRID2023 to a 2021 release would price that year on a grid two years too new.

4. 04

   No upstream factors

   EPA publishes no well-to-tank figures. Slate reports that as a publication boundary and moves on, instead of quietly reusing the direct factor.

5. 05

   Errors the import caught

   Moving from hand-entered tables to EPA's own files corrected on-road gasoline using the aviation gasoline CO₂ factor (8.31 vs 8.78 kg/gal), non-road CH₄ and N₂O stored per mile instead of per gallon, and a mislabelled eGRID vintage.

Check a figure yourself

1. 1

   Download the Hub workbook for the record's year.

2. 2

   Find the table and fuel or vehicle shown in the provenance panel. EPA has no row IDs, so Slate builds one from the table and row labels.

3. 3

   Multiply by the GWP set named on the row to reproduce the CO₂e figure.

Licence and attribution

Licence

U.S. Government work (public domain)

Attribution

Source: U.S. EPA, GHG Emission Factors Hub and eGRID.