Understanding Greenhouse Gas Emissions From Natural Gas – EPA 2023 Inventory (1990-2021)

Climate change is a defining challenge globally. Natural gas, gas utilities, and the delivery infrastructure are essential to meeting our nation’s greenhouse gas (GHG) emissions reduction goals, including pathways to achieve net-zero emissions.

Natural gas is a fuel of choice for consumers because of its low cost, efficient end uses, and environmental attributes. Natural gas is a domestically produced and abundant energy source that presents the U.S. with an opportunity to address our energy, economic, and environmental objectives while serving as a foundational fuel for the U.S. economy for years to come. This potential has focused public attention on the environmental footprint of energy production, transportation, distribution, and end-use.

Efficient natural gas technologies are low-cost, low-emission options for building energy needs, home comfort, industrial processes, and electricity generation. Natural gas is a low-carbon fuel relative to coal and oil, resulting in less carbon dioxide (CO2) for the same amount of valuable energy. A better understanding of methane (CH4) emissions released from production and delivery systems will further clarify how using natural gas may deliver greater environmental benefits.

Since the early 1990s, the United States Environmental Protection Agency (EPA) has developed and published estimates of GHG emissions in its annual Inventory of U.S. Greenhouse Gas Emissions and Sinks (referenced throughout as the GHGI or “Inventory”). The GHGI is the most comprehensive assessment of U.S. GHG emissions available. The Inventory covers the most important GHGs emitted by human activity, including CO2, CH4, nitrous oxide (N2O), and several fluorine-containing halogenated substances. EPA reports all GHG emissions in units of carbon dioxide equivalents (CO2e) by weighting different air emissions by their respective global warming potentials (GWPs) to account for varying levels of radiative forces of each gas relative to CO2 over a 100-year time horizon.

EPA published its annual Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2021 in April 2023 (2023 GHGI). The 2023 GHGI updates the U.S. Greenhouse Gas Emissions and Sinks: 1990-2020 published in April 2022 (2022 GHGI) and incorporates new data from GHG emissions studies and the EPA’s Greenhouse Gas Reporting Program (GHGRP).

This report details data and commentary from the Inventory’s section on the natural gas system. The American Gas Association (AGA) contracted SLR Consulting to present effectively the data and analysis outlined in the Inventory. AGA then provided additional analysis adding context and perspective to the report and retrospective changes throughout the Inventory.

Read the full report here.