NukeGryd
Market Briefing · updated daily

Markets

Where U.S. nuclear supply is tightest right now, and what is coming off line next. As of Oct 9, 2026 · Updated every morning from the NRC Daily Power Reactor Status Report.
Most-stressed Market
SPP
39.6% offline · 772 MW
MW in Refueling Now
13,539 MW
13 units at a full outage
MW at Risk · Next 60 Days
megawatts due off line within 60 days
Biggest 30-day Mover
SPP
availability ▼ 34.5 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
27,090 MW
82.9% available 0 MW DoD
vs 7d avg−299 MW (−1.1%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 1,231 MW
What to watch Active: Susquehanna 1 · −1,247 MW since Sep 29, 2026
ISO / RTO 13u
9,709 MW
84.3% available ↘ 6 MW DoD
vs 7d avg−92 MW (−0.9%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 676 MW
What to watch Active: Callaway · −1,190 MW since Sep 26, 2026
Vertically Integrated 7u
TVA
5,827 MW
71.2% available 0 MW DoD
vs 7d avg−154 MW (−2.6%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 510 MW
What to watch Active: Browns Ferry 1 · −1,227 MW since Sep 6, 2026
Vertically Integrated 8u
6,875 MW
85.1% available ↘ 9 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 387 MW
What to watch Active: Vogtle 2 · −1,152 MW since Aug 22, 2026
Vertically Integrated 7u
7,226 MW
100.0% available 0 MW DoD
vs 7d avg+577 MW (+8.7%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 359 MW
What to watch All units at full power
ISO / RTO 4u
4,986 MW
100.0% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 8 MW
What to watch All units at full power
Vertically Integrated 3u
SRP
2,626 MW
66.7% available 0 MW DoD
vs 7d avg−187 MW (−6.7%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 93 MW
What to watch Active: Palo Verde 1 · −1,311 MW since Oct 3, 2026
Vertically Integrated 4u
FPL
3,649 MW
100.0% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 36 MW
What to watch All units at full power
Vertically Integrated 4u
2,834 MW
78.9% available 0 MW DoD
vs 7d avg−99 MW (−3.4%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 72 MW
What to watch Active: Robinson 2 · −759 MW since Sep 24, 2026
ISO / RTO 3u
3,352 MW
100.0% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 22 MW
What to watch All units at full power
ISO / RTO 4u
3,329 MW
100.0% available 0 MW DoD
vs 7d avg+350 MW (+11.7%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 220 MW
What to watch All units at full power
ISO / RTO 2u
2,240 MW
100.0% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 21 MW
What to watch All units at full power
ISO / RTO 2u
SPP
1,177 MW
60.4% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 137 MW
What to watch Active: Cooper · −772 MW since Aug 13, 2026
Vertically Integrated 1u
BPA
1,151 MW
100.0% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 0 MW
What to watch All units at full power
Vertically Integrated 1u
977 MW
100.0% available 0 MW DoD
vs 7d avg0 MW (0.0%)
vs 1 yr ago██
Fleet record ██ ██
Fall 26 avg offline 0 MW
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 days
Market
◀ less onlinemore online ▶
30 days ago → now
Change
30-day trend
SPP
94.9% → 60.4%
↘ −34.5 pp
SRP
100.0% → 66.7%
↘ −33.3 pp
TVA
99.4% → 71.2%
↘ −28.2 pp
Duke Progress
100.0% → 78.9%
↘ −21.1 pp
Duke Carolinas
84.0% → 100.0%
↗ +16.0 pp
MISO
99.2% → 84.3%
↘ −14.9 pp
Southern
97.1% → 85.1%
↘ −12.0 pp
PJM
91.1% → 82.9%
↘ −8.2 pp
NYISO
95.7% → 100.0%
↗ +4.3 pp
No net change · 6 markets
ERCOT 100.0% · steady
FPL 100.0% · dipped to 97.3%
ISO-NE 100.0% · steady
CAISO 100.0% · dipped to 75.5%
BPA 100.0% · steady
Dominion SC 100.0% · steady
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
MarketTypeUnits Availability MW Offline % Offline Grid tomorrow 30d Δavail
SPP ISO/RTO 2 60.4% 772 39.6% normal ▼ 34.5
SRP Non-ISO 3 66.7% 1,311 33.3% — ▼ 33.3
TVA Non-ISO 7 71.2% 2,353 28.8% — ▼ 28.2
Duke Progress Non-ISO 4 78.9% 759 21.1% — ▼ 21.1
PJM ISO/RTO 31 82.9% 5,601 17.1% soft ▼ 8.2
MISO ISO/RTO 13 84.3% 1,803 15.7% normal ▼ 14.9
Southern Non-ISO 8 85.1% 1,205 14.9% — ▼ 12.0
Duke Carolinas Non-ISO 7 100.0% — 0.0% — ▲ 16.0
BPA Non-ISO 1 100.0% — 0.0% — ▲ 0.0
ERCOT ISO/RTO 4 99.5% — 0.0% soft ▲ 0.0
CAISO ISO/RTO 2 100.0% — 0.0% tight ▲ 0.0
NYISO ISO/RTO 4 99.8% — 0.0% soft ▲ 4.3
ISO-NE ISO/RTO 3 100.0% — 0.0% soft ▲ 0.0
FPL Non-ISO 4 100.0% — 0.0% — ▲ 0.0
Dominion SC 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.

Which market is about to be short, and by how much

Which units come off line next, when, and how much capacity is at risk by market (our sourced dates plus model projections) is part of NukeGryd Individual and up. Today's live market stress stays free.

See plans

Ontario (IESO) separate fleet

Ontario detail
MW Offline
4,600 MW
37.8% of the Ontario fleet
Units Offline
7 of 16
Bruce, Darlington, Pickering
Delivering
7,520 MW
of 12,160 MW installed
Resolution
1 hour
vs. once-daily for the U.S. fleet

Ontario supply, for the northeast picture. Ontario is reported as a separate fleet and is never added into the U.S. national figures above. IESO grid-operator market data (MW delivered), not NRC percent-power.