Long-Run Marginal Emission Rates for U.S. Electricity Grid

A source of modeled estimates of long-run marginal emission rates (LRMER) for the contiguous United States' electric sector. It covers 18 GEA regions, with mappings to ZIP codes and counties provided in the workbooks. The data is produced by the Department of Energy and is planned for annual updates.

Use Cases

• Analyze LRMER variations across the 18 GEA regions to identify high-impact areas for demand-side interventions.
• Map county or ZIP code level LRMER estimates to local energy consumption data for granular carbon footprint calculations.
• Use the LRMER projections to model the long-term emissions impact of new electricity demand from technologies like electric vehicles or data centers.
• Compare modeled LRMER values against historical grid emission factors to assess the influence of projected structural changes in the power sector.

Strengths

• Covers the entire contiguous United States through 18 distinct GEA regions.
• Provides spatial mappings to ZIP codes and counties for local analysis.
• Data is planned for annual updates, supporting time-series analysis.
• Associated with a detailed methodology report from the Department of Energy.

Limitations

• Data is modeled and projected, not directly measured, introducing inherent uncertainty.
• The specific limitations and caveats of the model are detailed in a separate report, requiring additional review.
• The dataset's structure (rows, columns) and sample data are not explicitly described in the input.

Provenance

Source

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

Collection Method

Modeled estimates from the Cambium 2023 scenario modeling project.

Time Range

Projection data for 2023 and future years (based on Cambium 2023 scenarios).

Freshness

Planned annual updates; last updated March 2026.

Geography

Contiguous United States, aggregated into 18 GEA regions with county and ZIP code mappings.