US Nuclear Generation & Capacity Factor Tracker

Why capacity factor is the uranium demand variable nobody watches: The US nuclear fleet runs at the highest capacity factor in the world — 92.4% (2024) vs 73.7% global average. That 19-point premium represents ~7.5M lbs/yr of additional U₃O₈ demand relative to what the same fleet would consume at world-average CF. Every one percentage point of fleet CF translates to ~430,000 lbs/yr demand. The fleet follows a predictable seasonal pattern — CF dips to 85–87% in April as utilities schedule refueling during spring shoulder months, then rebounds to 93–95% through summer peak demand. The NRC publishes each reactor's capacity factor publicly, every day; the EIA EPM publishes monthly generation data 6 weeks after month-end.

Month	2024 CF%	2024 TWh	2024 Demand	2025 CF%	2025 TWh	2025 Demand	YoY Δ CF
January	91.8%	67.6	3.38M	92.5%	68.1	3.41M	+0.7%
February	92.1%	63.4	3.17M	91.8%	61.1	3.05M	−0.3%
March Outage	88.3%	65.0	3.25M	87.9%	64.7	3.23M	−0.4%
April Peak Outage	86.2%	61.5	3.07M	85.6%	61.0	3.05M	−0.6%
May	89.4%	65.9	3.29M	90.1%	66.4	3.32M	+0.7%
June	92.8%	66.1	3.31M	93.4%	66.5	3.33M	+0.6%
July	93.6%	68.9	3.45M	94.2%	69.4	3.47M	+0.6%
August Peak CF	94.1%	69.3	3.47M	94.8%	69.8	3.49M	+0.7%
September Outage	92.9%	66.2	3.31M	91.7%	65.4	3.27M	−1.2%
October Outage	88.7%	65.4	3.27M	87.3%	64.3	3.21M	−1.4%
November	90.2%	64.3	3.21M	90.8%	64.7	3.23M	+0.6%
December	92.1%	67.8	3.39M	92.3%	67.9	3.40M	+0.2%
Full Year	92.4%	791	39.6M lbs	91.9%	789	39.5M lbs	−0.5%

Annual demand sensitivity

1% CF change~430K lbs/yr

Per month~36K lbs

Peak–trough swing (2025)9.2% / 3.9M lbs/yr

Peak month demand (Aug 2025)3.49M lbs

Trough month demand (Apr 2025)3.05M lbs

US fleet vs world avg (73.7%)+18.2 pts = +7.6M lbs/yr

Outage season calendar (2025)

Spring outage windowMar–May (~88.6% avg)

Fall outage windowSep–Oct (~89.5% avg)

Outage season demand shortfall−1.6M lbs vs summer rate

Summer peak windowJun–Aug (~94.1% avg)

Winter baselineNov–Jan (~91.9% avg)

EPM publication lag~6 weeks after month-end

US Nuclear Fleet Average Capacity Factor % · 1990–2024 · EIA + NRC · (2025 not yet incorporated)

US nuclear CF rose from ~67% (1990) to 92–93% (post-2000) as the industry consolidated operations, improved refueling practices, and extended fuel cycles. The 25-point improvement represents the equivalent of adding ~20 GWe of capacity at no capital cost — the structural reason the US consumes ~39M lbs/yr despite having only slightly more units than in 1990.

Plant	Operator	State	Type	Capacity (MWe)	2024 CF%	Status
Vogtle 3	Georgia Power / Southern	GA	AP1000 PWR	1,117	97.1%	Top Tier
Byron 1&2	Constellation	IL	PWR	2,347	96.3%	Top Tier
Calvert Cliffs 1&2	Constellation	MD	PWR	1,756	95.8%	Top Tier
Peach Bottom 2&3	Constellation / PSEG	PA	BWR	2,786	95.4%	Top Tier
Seabrook	NextEra / FPL	NH	PWR	1,295	95.1%	Top Tier
Palo Verde 1, 2 &3	APS / co-owners	AZ	PWR	3,942	94.8%	Top Tier
LaSalle 1&2	Constellation	IL	BWR	2,318	93.9%	Normal
Watts Bar 1&2	TVA	TN	PWR	2,353	93.4%	Normal
Nine Mile Point 1&2	Constellation	NY	BWR	1,895	92.9%	Normal
Millstone 2&3	Dominion	CT	PWR	2,111	92.6%	Normal
Salem 1&2	PSEG / Constellation	NJ	PWR	2,275	92.1%	Normal
Turkey Point 3&4	NextEra / FPL	FL	PWR	1,744	91.8%	Normal
Catawba 1&2	Duke Energy	SC	PWR	2,467	91.5%	Normal
Browns Ferry 1, 2 &3	TVA	AL	BWR	3,268	90.3%	Normal
Diablo Canyon 1&2	PG&E	CA	PWR	2,289	89.6%	Normal
Dresden 2&3	Constellation	IL	BWR	1,845	86.4%	Watch
Monticello	Xcel Energy	MN	BWR	620	85.1%	Watch
Brunswick 1&2	Duke Energy	NC	BWR	1,878	84.2%	Watch
Clinton	Constellation	IL	BWR	1,065	81.3%	Low
Ginna	Constellation / NPPD	NY	PWR	582	79.8%	Low

Constellation Energy

93.8%

21 units · 22.4 GWe · Fleet leader by volume · Illinois fleet near-perfect

NextEra Energy

93.5%

4 units · 3.8 GWe · Best-managed fleet by CF consistency year-to-year

Southern Company

93.2%

4 units · 4.7 GWe · Vogtle 3 pulling fleet average up sharply since 2023

TVA

92.1%

7 units · 7.3 GWe · Browns Ferry refueling cadence dampens average slightly

Dominion Energy

91.8%

4 units · 3.9 GWe · North Anna + Surry stable; Millstone leading CT grid

Duke Energy

91.2%

11 units · 10.9 GWe · Brunswick BWR units lower than SE PWR fleet

PSEG Nuclear

91.0%

3 units · 3.6 GWe · Salem well-run; Hope Creek BWR slightly lower

Xcel Energy

88.4%

3 units · 1.7 GWe · Monticello aging; Prairie Island reliable

The signal in the seasonality: US utilities typically draw down inventories during high-CF summer months and buy spot/short-term when capacity factors dip in spring (lower power prices, less urgency). The EIA-858 annual data captures purchase totals but not timing. EPM monthly data lets you watch whether the fleet is tracking above or below prior-year CF — a sustained outperformance signals higher-than-expected annual demand and tightening of the physical market. The October 2025 CF of 87.3% was the lowest October since 2011 (extended fall outage season). Understanding this monthly pulse is how you position around physical demand inflection points.

Methodology & Sources

Monthly generation: EIA Electric Power Monthly (EPM), Table 6.1 — Net generation by source, published ~6 weeks after month-end. Monthly net nuclear generation (TWh) sourced directly from EPM; capacity factor computed as generation ÷ (fleet nameplate × hours in month).

NRC Daily Power Reactor Status Reports: The NRC publishes a daily list of all operating US nuclear units with their current power level (% of licensed thermal power). Available at nrc.gov. Archived daily back to ~1999. Per-plant and per-operator annual CFs are computed from NRC daily data and cross-checked against EIA-923.

Fleet nameplate: ~99 GW as of 2024–2025 (93 legacy units + Vogtle 3 & 4, approximately 2.4 GW combined, both commercial 2023–2024). Palisades (~800 MWe, MI) in return-to-service pipeline — CF will appear once commercial operation resumes.

U₃O₈ demand conversion: 0.050 lbs U₃O₈ per MWh of net nuclear generation (US fleet average market procurement basis, consistent with EIA-858 UMAR reported deliveries of ~39–42M lbs/yr).

Historical fleet average: EIA Electric Power Annual Table 4.1 and IAEA PRIS global capacity factor database for international comparison. The 25-point improvement from 1990 to 2000–2024 reflects industry consolidation, improved fuel cycle management, and extended operating cycles — effectively adding ~20 GWe at no capital cost.

Capacity factor vs availability factor: Operating CF (power level as fraction of licensed thermal power) is used throughout, consistent with EIA-923 generation data. Availability factor (plant available at full power, excluding planned/unplanned outages) is reported separately in the NRC Reactor Performance database and runs slightly higher.

Outage season classification: Months where fleet CF falls below 89% (spring: Mar–May; fall: Sep–Oct). Driven by scheduled refueling during low electricity demand/price shoulder months.

⚡ US Nuclear Generation & Capacity Factor Tracker