2025 SRMS Update: Expanding the Framework for CO2 Storage Resources Classification and Management

The SPE CO₂ Storage Resources Management System (SRMS), first published in 2017, is a system that aims to provide the carbon capture and storage (CCS) community with a standard for storage resources classification and categorization. The SRMS provides a consistent approach to estimate Storable Quantities, evaluate the commerciality of projects, and present results in a comprehensive classification framework. It provides all stakeholders (governments, regulators, financial entities, etc.) a means for comparing and contrasting CO₂ storage estimates based on project maturity and geologic certainty. It also provides context for an investment and tracking the performance of the investment. The SRMS classification is aligned with that of the time-tested and widely used Petroleum Resources Management System (PRMS). The SRMS has been adopted by the industry (e.g., Santos, and the US Department of Energy) in CO₂ storage management. The 2025 SRMS Update was approved for publication by the SPE Board in January 2025 along with the endorsement of six sponsoring societies. The update involved a 2-year review process led by a CO₂ Storage Resources Committee (CSRC) working group. Like the original 2017 SRMS, the 2025 SRMS Update contains four major sections: Basic Principles and Definitions, Classification and Categorization Guidelines, Evaluation and Reporting Guidelines, and Estimating Storable Quantities, plus an Appendix covering the glossary of terms. In preparing the update, the working group held multiple consultations and solicited input from interested parties, stakeholders and the public. Every comment received was carefully reviewed and addressed to ensure the updated document reflected the broad range of perspectives. The most significant distinction between the 2017 SRMS and the 2025 SRMS Update is that the former focused on pure geologic storage while the latter also incorporates CO₂ EOR as a form of storage. The following is a summary of the main aspects of the 2025 SRMS Update and the key changes made to the 2017 SRMS.