The development of the Natural Gas Sustainability Initiative (NGSI) was launched by the Edison Electric Institute (EEI)-American Gas Association (AGA) CEO Natural Gas Task Force in 2018. Recognizing the critical role of natural gas across the economy, EEI and AGA designed the NGSI along with facilitator MJ Bradley & Associates, an ERM Group company, to respond to the rising importance of climate change and sustainability for customers, investors, and other stakeholders. The NGSI Methane Emissions Intensity Protocol Version 1.0 was released in February 2021. EEI and AGA, together with facilitator SLR International Corporation, released the Version 2.0 in 2024 to incorporate updated emission factors and maintain consistent with other standardized approaches for calculating methane intensity.

NGSI is a voluntary, industry-wide approach for companies to calculate methane emissions intensity by segment—the Methane Emissions Intensity Protocol (Protocol). Developing a consistent, transparent, and comparable method for measuring and reporting methane emissions throughout the natural gas supply chain will improve the quality of information available from the industry and will help companies more effectively identify ways to reduce methane emissions and communicate progress. This is not meant to replace regulations, but to provide a meaningful tool to increase transparency and to facilitate improvements.

The NGSI Methane Emissions Intensity Protocol, Version 2.0, was released in September 2024. Version 2.0 remains aligned with the version of EPA’s Greenhouse Gas Reporting Program (GHGRP) Subpart W regulations for Petroleum and Natural Gas Systems that were in effect as of January 1, 2024. Version 2.0 does not incorporate the recent revisions to Subpart W nor the GHGRP revisions to subparts other than Subpart W that take effect on January 1, 2025. These final GHGRP revisions will be incorporated, as applicable, into a subsequent update to the NGSI Protocol and its accompanying reporting templates. Version 2.0 includes a Protocol overview (PDF) and five data reporting templates (Excel spreadsheets), one for each of the following segments of the natural gas value chain: onshore production, gathering and boosting, processing, transmission and storage, and distribution. The resulting methane emissions intensity metric can be disclosed by EEI and AGA members on the EEI-AGA ESG Reporting Template as well as their company-specific sustainability webpage. Non-EEI and AGA members may consider disclosing the metric on their sustainability webpage.