EPA (Environmental Protection Agency)
The EPA is the United States federal agency responsible for protecting human health and the environment. It runs the Greenhouse Gas Reporting Program (GHGRP) and publishes emission factors and tools used in US carbon accounting.
The Environmental Protection Agency (EPA) was established in 1970 and sets and enforces environmental regulations in the United States. For carbon accounting, its two most important programs are the Greenhouse Gas Reporting Program (GHGRP) and the USEEIO model.
GHGRP is a mandatory reporting program under 40 CFR Part 98. It requires roughly 8,000 large facilities and fuel suppliers to report annual GHG emissions. Covered sources include power plants, refineries, petrochemical facilities, landfills, and suppliers of fossil fuels and industrial gases. The data is public and covers about half of total US GHG emissions directly, and 85-90% when suppliers are included.
USEEIO is the EPA's environmentally extended input-output model. It provides spend-based emission factors by North American Industry Classification System (NAICS) code, widely used for Scope 3 Category 1 (purchased goods and services) estimates when supplier-specific data is unavailable. Carbon accounting platforms use USEEIO factors to produce initial Scope 3 footprints that can be refined over time.
The EPA also publishes the Emissions and Generation Resource Integrated Database (eGRID), which contains grid emission factors for US electricity. eGRID factors are essential for Scope 2 location-based reporting.
Frequently asked questions
What is the EPA Greenhouse Gas Reporting Program? +
The Greenhouse Gas Reporting Program (GHGRP) is a mandatory EPA program requiring about 8,000 large US facilities and fuel suppliers to report annual greenhouse gas emissions. The data is public and covers roughly half of total US emissions.
What emission factors does the EPA publish? +
The EPA publishes USEEIO spend-based emission factors for Scope 3 estimates and eGRID grid emission factors for Scope 2 electricity calculations. It also provides greenhouse gas emission factors through GHGRP reporting and other inventories.
Who has to report to the EPA GHGRP? +
Large direct emitters, fuel suppliers, and industrial gas suppliers that exceed EPA-defined thresholds must report. This includes power plants, refineries, manufacturing facilities, landfills, and suppliers of natural gas, petroleum products, and industrial gases.
Related terms
Emission Factor
An emission factor is a coefficient that converts an activity measurement — such as litres of fuel burned, kilowatt-hours of electricity consumed, or dollars spent on a commodity — into a quantity of greenhouse gas emissions, typically expressed in kilograms or tonnes of CO₂ equivalent (tCO₂e).
Scope 1 Emissions
Scope 1 emissions are direct greenhouse gas emissions from sources that an organization owns or controls. This includes combustion of fossil fuels in owned boilers, furnaces, and vehicles; process emissions from manufacturing; and fugitive emissions such as refrigerant leaks and methane from owned landfills.
Scope 2 Emissions
Scope 2 emissions are indirect greenhouse gas emissions from the generation of purchased electricity, steam, heating, and cooling consumed by an organization. They are called 'indirect' because the emissions physically occur at the power plant or utility, not at the reporting company's facilities.
Scope 3 Emissions
Scope 3 emissions are all indirect greenhouse gas emissions that occur in an organization's value chain — both upstream (suppliers, purchased goods, business travel, employee commuting) and downstream (product use, end-of-life treatment, investments). Scope 3 typically represents 70–90% of a company's total carbon footprint.
EEIO
EEIO (Environmentally Extended Input-Output) is an economic modeling approach that estimates greenhouse gas emissions per dollar of economic output by industry sector, commonly used for Scope 3 spend-based emissions calculations.
GHG Protocol
The GHG Protocol is the world's most widely used greenhouse gas accounting standard. Developed by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD), it provides frameworks for organizations, cities, and countries to measure and manage their emissions across three scopes.