Market Briefing · live
Markets
Where U.S. nuclear supply is tightest right now, and what is coming off line next. As of Aug 21, 2026 · Updated every morning from the NRC Daily Power Reactor Status Report.
Most-stressed Market
MISO
5.6% offline · 650 MW
MW in Refueling Now
617 MW
1 unit at a full outage
MW at Risk · Next 60 Days
paid · capacity at risk in 60 days
Biggest 30-day Mover
MISO
availability ▼ 5.3 pts
By Market
Available nuclear MW now, the day's move, vs 7-day and a year ago, and the 30-day trend, by balancing authority
ISO / RTO
31u
PJM
32,307 MW
98.8% available
↘ 197 MW DoD
vs 7d avg−157 MW (−0.5%)
vs 1 yr ago−171 MW (−0.5%)
Availability · 30d97.2% → 100.0%
ISO / RTO
13u
MISO
10,862 MW
94.4% available
0 MW DoD
vs 7d avg+28 MW (+0.3%)
vs 1 yr ago−459 MW (−4.1%)
Availability · 30d86.1% → 99.7%
Vertically Integrated
7u
TVA
8,181 MW
100.0% available
0 MW DoD
vs 7d avg+39 MW (+0.5%)
vs 1 yr ago0 MW (0.0%)
Availability · 30d96.7% → 100.0%
What to watch
All units at full power
Vertically Integrated
8u
Southern (SOCO)
8,080 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago+45 MW (+0.6%)
Availability · 30d100.0% → 100.0%
What to watch
All units at full power
Vertically Integrated
7u
Duke Carolinas (DUK)
7,191 MW
99.5% available
0 MW DoD
vs 7d avg−25 MW (−0.3%)
vs 1 yr ago−35 MW (−0.5%)
Availability · 30d99.5% → 100.0%
ISO / RTO
4u
ERCOT
4,986 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago0 MW (0.0%)
Availability · 30d100.0% → 100.0%
What to watch
All units at full power
Vertically Integrated
3u
Palo Verde / SRP
3,937 MW
100.0% available
0 MW DoD
vs 7d avg+6 MW (+0.1%)
vs 1 yr ago0 MW (0.0%)
Availability · 30d98.3% → 100.0%
What to watch
All units at full power
Vertically Integrated
4u
Florida Power & Light (FPL)
3,649 MW
100.0% available
0 MW DoD
vs 7d avg+207 MW (+6.0%)
vs 1 yr ago−17 MW (−0.5%)
Availability · 30d73.1% → 100.0%
What to watch
All units at full power
Vertically Integrated
4u
Duke Progress (CPLE)
3,593 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago0 MW (0.0%)
Availability · 30d86.6% → 100.0%
What to watch
All units at full power
ISO / RTO
3u
ISO-NE
3,352 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago+52 MW (+1.6%)
Availability · 30d74.2% → 100.0%
What to watch
All units at full power
ISO / RTO
4u
NYISO
3,241 MW
97.4% available
0 MW DoD
vs 7d avg−12 MW (−0.4%)
vs 1 yr ago−85 MW (−2.6%)
Availability · 30d97.4% → 100.0%
ISO / RTO
2u
CAISO
2,240 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago0 MW (0.0%)
Availability · 30d100.0% → 100.0%
What to watch
All units at full power
ISO / RTO
2u
SPP
1,902 MW
97.6% available
↘ 8 MW DoD
vs 7d avg−11 MW (−0.6%)
vs 1 yr ago−46 MW (−2.4%)
Availability · 30d88.1% → 100.0%
Vertically Integrated
1u
Bonneville (BPAT)
1,151 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago0 MW (0.0%)
Availability · 30d100.0% → 100.0%
What to watch
All units at full power
Vertically Integrated
1u
Dominion SC (SCEG)
977 MW
100.0% available
0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago+68 MW (+7.5%)
Availability · 30d100.0% → 100.0%
What to watch
All units at full power
Available MW = nuclear generating MW now (installed nuclear MW minus what is offline), at the 98% full-power floor. DoD is the change since yesterday; the 30-day spark is the market's availability (% of its nuclear fleet generating). "What to watch" is the largest unit offline now, with the date it went down.
Biggest 30-Day Movers
Signed change in nuclear availability over the last 30 daysMISO
↘ −5.3 pp
Florida Power & Light (FPL)
↗ +3.9 pp
NYISO
↘ −2.6 pp
SPP
↘ −2.4 pp
PJM
↘ −1.2 pp
Duke Carolinas (DUK)
↘ −0.5 pp
TVA
↗ +0.0 pp
Southern (SOCO)
↗ +0.0 pp
ERCOT
↗ +0.0 pp
Palo Verde / SRP
↗ +0.0 pp
Duke Progress (CPLE)
↗ +0.0 pp
ISO-NE
↗ +0.0 pp
CAISO
↗ +0.0 pp
Bonneville (BPAT)
↗ +0.0 pp
Dominion SC (SCEG)
↗ +0.0 pp
Change in each market's nuclear availability (generating MW as a share of installed nuclear MW) between 30 days ago and today. Positive points = more nuclear back online.
Most-stressed Markets
By share of nuclear fleet offline, lowest availability first| Market | Type | Units | Availability | MW Offline | % Offline | Grid tomorrow | 30d Δavail |
|---|---|---|---|---|---|---|---|
| MISO | ISO/RTO | 13 | 94.4% | 650 | 5.6% | soft | ▼ 5.3 |
| NYISO | ISO/RTO | 4 | 97.4% | 85 | 2.6% | soft | ▼ 2.6 |
| SPP | ISO/RTO | 2 | 97.6% | 46 | 2.4% | tight | ▼ 2.4 |
| PJM | ISO/RTO | 31 | 98.8% | 385 | 1.2% | soft | ▼ 1.2 |
| Duke Carolinas (DUK) | Non-ISO | 7 | 99.5% | 35 | 0.5% | – | ▼ 0.5 |
| TVA | Non-ISO | 7 | 99.8% | – | 0.0% | – | ▲ 0.0 |
| Duke Progress (CPLE) | Non-ISO | 4 | 100.0% | – | 0.0% | – | ▲ 0.0 |
| Bonneville (BPAT) | Non-ISO | 1 | 100.0% | – | 0.0% | – | ▲ 0.0 |
| ERCOT | ISO/RTO | 4 | 100.0% | – | 0.0% | normal | ▲ 0.0 |
| CAISO | ISO/RTO | 2 | 100.0% | – | 0.0% | soft | ▲ 0.0 |
| Southern (SOCO) | Non-ISO | 8 | 99.7% | – | 0.0% | – | ▲ 0.0 |
| ISO-NE | ISO/RTO | 3 | 100.0% | – | 0.0% | soft | ▲ 0.0 |
| Palo Verde / SRP | Non-ISO | 3 | 100.0% | – | 0.0% | – | ▲ 0.0 |
| Florida Power & Light (FPL) | Non-ISO | 4 | 100.0% | – | 0.0% | – | ▲ 3.9 |
| Dominion SC (SCEG) | Non-ISO | 1 | 100.0% | – | 0.0% | – | ▲ 0.0 |
Availability = nuclear generating MW ÷ installed nuclear MW. "Grid tomorrow" is the day-ahead demand forecast vs the trailing-30-day norm, where a nuclear loss bites hardest. 30d Δavail is the change in the market's nuclear availability over the last 30 days.
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