Data Methodology

This page documents how PowerPlantsNearMe.com collects, joins, and serves U.S. power plant data. If you are citing this site in academic research, journalism, or policy work, please reference this page and the original federal sources described below.

Data Sources

EIA Form 860 — Generators and plants

The backbone dataset. EIA-860 is an annual census of existing and planned generators at electric generating plants with 1 MW or greater of combined nameplate capacity. Published each summer by the U.S. Energy Information Administration for the prior reporting year. We import plant-level records with valid coordinates, plus generator-level detail (technology, prime mover, operating year, retirement status, ownership). Our runtime database contains 16,132 plants drawn from EIA-860.

Source: eia.gov/electricity/data/eia860/

EIA Form 923 — Generation and fuel consumption

Monthly generation and fuel consumption reporting from plants that meet EIA-923's reporting thresholds. Published with a three-to-six-month lag. We roll up the monthly records to annual totals per plant and use the most recent complete year available. These values drive the "Annual Net Generation (MWh)" and capacity factor figures you see on plant pages and state summaries.

Source: eia.gov/electricity/data/eia923/

EPA eGRID — Emissions

eGRID (Emissions & Generation Resource Integrated Database) is the EPA's comprehensive source of data on the environmental characteristics of U.S. electricity generation. Published every one to two years. We join eGRID plant records to EIA-860 by plant_code (the EIA ORISPL) and pull annual CO\u2082, SO\u2082, and NO\u2093 totals plus CO\u2082 emission rate in pounds per MWh. Non-combustion plants correctly show zero emissions.

Source: epa.gov/egrid

GeoNames — ZIP centroids

GeoNames publishes free postal code centroids with latitude, longitude, state, and county for every U.S. ZIP code. We use these to power the /near/{zip} proximity lookup — resolving a ZIP to a lat/lng and then running the same haversine search used by the address lookup. Our database contains 41,488 U.S. ZIP centroids.

Source: download.geonames.org/export/zip/

Join Strategy

All four datasets are keyed on the EIA ORISPL plant code (plant_code). Plants flow from EIA-860 as the authoritative row; generation and fuel consumption are aggregated from EIA-923 by plant code and summed across generators; emissions are pulled from eGRID by plant code. Where eGRID does not report a plant (e.g. small non-fossil plants below the reporting threshold), emissions fields remain NULL rather than zero.

Generators, ownership, and monthly generation tables are retained in the raw form and queried per-request when a user views a plant detail page.

Runtime Tables

The web app reads from a small set of materialized views built by scripts/build-runtime.sql after each ingest:

• plants — one row per EIA-860 plant with joined eGRID emissions and EIA-923 generation totals. 16,132 rows.
• state_summary — state-level aggregates (plant count, total capacity, total generation, fuel mix). 51 rows.
• county_summary — county-level aggregates.
• fuel_summary — fuel-category-level aggregates (13 categories).

These tables are cheap to rebuild and the web app opens the SQLite database read-only at startup.

Known Limitations

• Reporting lag. EIA-923 runs 3–6 months behind; eGRID runs 12–18 months behind. The most recent full calendar year of generation/emissions data is always at least a few months old.
• Missing emissions. Small fossil plants below eGRID's reporting threshold may appear with NULL emissions fields. Missing is not the same as zero.
• Retired plants. Plants retired after the most recent EIA-860 release will still appear in the dataset. Generator-level status flags indicate retirement where known.
• Coordinate accuracy. Plant coordinates come from EIA-860 and are generally accurate to within a few hundred feet, but a handful of historical records place the pin at a town or county centroid rather than the actual facility.
• Rounding. Capacity is reported to the nearest MW. Generation values from EIA-923 are rounded to the nearest MWh. Small discrepancies between nameplate capacity sums and state totals reflect rounding in the source data.

Total capacity

Summed across all 16,132 plants in the runtime database, the total nameplate capacity is 1,362,085 MW MW. This figure will drift slightly between EIA-860 releases as plants come online, retire, or are re-classified.

Update Schedule

We rebuild the database from the latest available EIA and eGRID releases on a regular basis. The most recent build date of this deployment is: 2026-04-23.

Citation

If you use this data in research or publications, please use a citation format like the following and also cite the original federal sources:

PowerPlantsNearMe.com. (2026). U.S. Power Plant Directory, derived from EIA Form 860, EIA Form 923, and EPA eGRID. Retrieved [date] from https://powerplantsnearme.com/methodology

Downloads and API

Per-state CSV downloads are linked from each state page, or available directly at /api/download/{state}.csv. For programmatic access, see the free JSON API documentation.