Long-Run Marginal Emission Rates for U.S. Electricity in 2022

Modeled estimates of long-run marginal emission rates (LRMER) for the contiguous United States, developed by the Department of Energy. The data is available at two geographic resolutions: state-level and across 20 GEA regions. It is intended for assessing the emissions impact of long-lived interventions on the electricity grid.

Use Cases

• Compare long-run marginal emission rates (LRMER) between state and GEA region geographies to analyze spatial variability.
• Estimate the emissions impact of a new long-lived electricity demand project using the LRMER values for a specific state.
• Analyze how projected changes in grid structure, as captured by the LRMER model, influence emissions outcomes across different GEA regions.

Strengths

• Data is provided at two distinct geographic resolutions: state-level and 20 GEA regions.
• Modeled estimates account for changes in both grid operation and long-term infrastructure (generators, transmission lines).
• Associated with the Cambium 2022 project and a detailed methodology report from the National Renewable Energy Laboratory (NREL).

Limitations

• Data is modeled, not directly measured, and depends on the assumptions and scenarios of the Cambium project.
• Geographic coverage is limited to the contiguous United States, excluding Alaska, Hawaii, and U.S. territories.
• The underlying file format (BIN) may require specific tools or software for access and interpretation.

Provenance

Source

Department of Energy, National Renewable Energy Laboratory (NREL) Cambium project.

Collection Method

Modeled estimates from the Cambium 2022 scenarios.

Time Range

Based on 2022 Cambium data and projections.

Freshness

Planned for annual updates; last updated in March 2026.

Geography

Contiguous United States, at state and GEA region (20 regions) resolution.