US nuclear outages hold at 19,860 MW on October 20, 2026, near the fall peak
US nuclear capacity offline was 19,860 megawatts (MW) on October 20, 2026, about 19.8% of the fleet. That is more than double the level of the third week of September, as plants shut for fall maintenance.
A data update from FactIQ, written from Energy Information Administration figures. What is FactIQ?
Key figures
- US nuclear capacity offline, October 20, 2026
- 19,860 MWagainst 19,896 MW on October 19 and roughly 7,700 MW in the third week of September2026-09-032026-10-20U.S. Daily Nuclear Capacity Outage
- Share of US nuclear capacity offline, October 20, 2026
- 19.8%normal for mid-October
- Total US nuclear power capacity
- 100,057 MW2026-09-032026-10-20U.S. Nuclear Power Capacity
- Comanche Peak 1 capacity offline since October 19
- 1,235 MWreduced output had grown from 25 MW to 124 MW since October 8
Nuclear outages barely changed and stay near their fall high
The Energy Information Administration (EIA) tracks how much US nuclear generating capacity is offline each day. Offline capacity cannot produce electricity, so the figure shows how much nuclear supply the power grid is missing.- Capacity offline was 19,860 megawatts (MW) on October 20, against 19,896 MW on October 19.
- That is about 19.8% of total US nuclear power capacity of 100,057 MW.
- Roughly 7,700 MW was offline in the third week of September.
- Outages around 20 gigawatts (GW) are normal for mid-October.
Two large jumps in October drove the rise
Several large units began fall maintenance at the same time on two days.- On October 3, outages rose from 12.3 GW to 16.1 GW. Palo Verde has had 1,333 MW out since that day.
- On October 12, outages rose from 17.4 GW to 19.8 GW. Peach Bottom in Pennsylvania (1,347 MW) and Millstone in Connecticut (1,252 MW) each took a unit fully offline.
- Byron has had 1,177 MW out since late September.
Comanche Peak 1 is the latest unit to go fully offline
Comanche Peak 1 in Texas went fully offline on October 19, taking out 1,235 MW. Since October 8 it had been cutting output gradually, with its reduced output growing from 25 MW to 124 MW. Browns Ferry partly offset this. Its outage fell from 1,255 MW to zero by October 15.Palisades still shows its entire 815.6 MW as offline on every day back to April. Its planned restart does not yet appear in EIA data.
Source: Energy Information Administration. See all EIA data in FactIQ.
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