A coal plant that closes leaves a lot behind: a grid connection, a transmission corridor, cooling water nearby, industrial land and a workforce that knows how to run a power plant. A reactor needs most of the same things.
The Department of Energy studied this in 2022. Its national laboratories screened 157 retired and 237 operating coal plant sites and found that 80% of those evaluated had the basic characteristics to host an advanced reactor, with overnight capital costs 15% to 35% lower than a greenfield build.
Where they are
Voltane Nuclear counts every US plant with coal units retired since 2002 or scheduled to retire, from EIA-860M. That gives 407 sites in 44 states. Of them, 42 still run coal units with a planned retirement date; the other 365 have retired all their coal. Together they held 192.9 GW of coal capacity. 4 of them are also an existing, shut-down or permitted nuclear site.
One square per state; darker means more sites. OH leads with 31, then PA (30), MI (25), IL (24) and IN (20). Data (JSON)
How they score
Coal sites score a little lower than the other candidates as a group. That is expected: the other candidates include existing nuclear plants and early site permits, which already passed far more scrutiny. But coal sites are a large share of the best: 26 of the 50 highest SMR scores are coal sites, and so are 28 of the best 50 for microreactors and 36 for large reactors.
Coal candidatesOther candidates
Median screening score out of 100. 87 coal sites score 80 or more for SMRs, 74 for microreactors and 53 for large reactors. Data (JSON)
Screening only — not a site suitability determination.
What makes a coal site strong
Compare the top quarter of coal sites by SMR score with the bottom quarter (101 sites each). The biggest difference is existing interconnection at the site: the top quarter averages 93% of full marks, the bottom quarter 20%. A plant that ran large units left a large connection behind. Next come distance to a population center (80% against 22%) and transmission access (99% against 62%).
| Criterion | Top quarter | Bottom quarter |
|---|---|---|
| Existing interconnection at the site | 93% | 20% |
| Distance to a population center | 80% | 22% |
| Transmission access | 99% | 62% |
| Flood hazard | 99% | 69% |
| Population exposure | 54% | 27% |
| Nearby external hazards | 74% | 61% |
| Major surface water nearby | 96% | 87% |
| Load proximity (data centers) | 65% | 55% |
| Distance to a Quaternary fault | 97% | 89% |
| Seismic hazard | 86% | 80% |
| Reusable industrial site | 82% | 80% |
Sorted by the gap between the two groups. Data (JSON)
The grid is usually still there. 301 coal sites (74%) have a 230 kV or higher line within 5 miles. The median coal site has 60,081 people within 10 miles. 55 sit inside the modelled hundred-year river flood extent (JRC / Copernicus, not a FEMA zone).
Weak coal sites tend to be small plants with little generation left behind, close to a city, or far from a strong line. A weak score is not a verdict: it says the screening criteria, at today's weights, favour other places first.
Screening only — not a site suitability determination.