Understanding Updates to the EPA Inventory of Greenhouse Gas Emissions from Natural Gas Systems

Report May 17, 2021

Understanding Updates to the EPA Inventory of Greenhouse Gases


The Environmental Protection Agency (EPA) made further updates to its estimates of methane emissions in its Inventory of US Greenhouse Gas Emissions and Sinks: 1990-2019. The Inventory incorporates new data available from studies on emissions as well as the EPA’s own Greenhouse Gas Reporting Program (GHGRP).

The Inventory reveals once again that natural gas distribution systems have a small emissions footprint shaped by a declining trend. The natural gas industry methane emissions accounts for only 2.7 percent of total greenhouse gas emissions. Distribution systems owned and operated by local natural gas utilities emit 0.08 percent of produced natural gas. These annual emissions declined 69 percent from 1990 to 2019, even as natural gas utility companies added more than 788,000 miles of pipeline to serve 21 million more customers.

This exceptional record can be traced to gas utilities continuing to make safety their top priority and remaining deeply committed to systematically upgrading infrastructure through risk-based integrity management programs. As companies and the country continue to modernize the natural gas infrastructure base and connect homes and businesses, there will be new opportunities to achieve low-cost carbon emissions reductions by leveraging this existing infrastructure and the nation’s abundant natural gas resource.

Key Findings:

  • Annual methane emissions from natural gas distribution systems declined 69 percent from 1990 to 2019.
  • The natural gas emissions rate of production from distribution systems remains unchanged at 0.08 percent.
  • Industry-wide natural gas emissions as a rate of production (the “leakage rate”) are now 1.0 percent – a level well below the most stringent thresholds for immediate climate benefits achieved through coal to natural gas switching.
  • Total methane emissions from natural gas systems have declined 16 percent from 1990 to 2019.
  • Methane emissions from all economic sectors represent 10 percent of all greenhouse gas emissions in the United States. Methane released from natural gas systems accounts for 2.7 percent of all US greenhouse gas emissions.

For more information, contact:

Gina DeFrancesco, Clean Energy Analyst, Energy Analysis

gdefrancesco@aga.org, (202) 824-7127