US EPA for GHG Inventories
The Environmental Protection Agency (EPA) is a United States government agency responsible for setting and enforcing national pollution standards. The EPA's GHG Emission Factors Hub provides organizations with a regularly updated, easy-to-use set of default emission factors for reporting greenhouse gas emissions. This tool helps organizations quantify emissions from various sources, supporting compliance with GHG reporting requirements and the establishment of climate goals.
The database includes emission factors for several key categories, such as: purchased electricity (derived from the eGRID system), mobile combustion, upstream and downstream transportation, business travel, product transport, and employee commuting.
Typically, greenhouse gas emissions are reported in units of carbon dioxide equivalent (CO2e). However, the emission factors in the database are initially expressed as CO2 and CH4. Continia has already converted these factors to CO2e by multiplying the emissions of each gas by its respective global warming potential (GWP), making them ready for immediate use.
The EPA uses various primary data sources to ensure accuracy and reliability in their emission factors, including:
- The Energy Information Administration (EIA) for energy-related data.
- Environmental Reporting by industries for industrial process emissions.
- National Inventory Reports for country-specific emissions tracking.
- The EPA’s eGRID database for electricity generation emission factors.
- The EPA’s MOBILE model for mobile combustion emissions
The US EPA GHG Emission Factors for Inventories primarily uses a top-down methodology, relying on national-level data such as fuel sales and energy production to estimate emissions for sectors like electricity, transportation, and industry. This approach provides sector-wide averages and aligns with the IPCC Guidelines for national GHG inventories. While predominantly top-down, the EPA sometimes integrates bottom-up elements for more detailed sectors, such as specific facility data or transportation models. Overall, this ensures comprehensive and consistent national emissions reporting.
For more information, visit the official EPA GHG Emission Factors Hub.