Recent Breaker-to-Breaker Achievements
Plants completing a full continuous operating cycle (Breaker-to-Breaker) in recent outage seasons. [View Full B2B Registry]
Spring 2026 3 units
Fall 2025 11 units
Spring 2025 15 units
Industry Average Capacity Factor by Year
Fleet-wide average capacity factor calculated from NRC daily reactor power data. Excludes decommissioned units after shutdown.
Latest (2025):
91.38%
13 years at or above 90%
Nuclear vs Other Energy Sources
Average capacity factors by energy source (EIA data, approximate industry averages). Nuclear consistently leads all major generation sources.
Breaker-to-Breaker Runs
Most vs Least successful continuous operating cycles [Full List]
Most
B2B Runs
- 1Byron 1 14
- 2Braidwood 1 12
- 3Catawba 2 12
- 4McGuire 2 12
- 5Oconee 2 12
Least
B2B Runs
- 1Watts Bar 2 0
- 2Vogtle 4 0
- 3Vogtle 3 0
- 4Pilgrim 1 0
- 5Oyster Creek 0
Construction Speed
Construction Permit to Operating License
Fastest
- 1Humboldt Bay 3 2.5y
- 2Yankee Rowe 3y
- 3San Onofre 1 3.2y
- 4Point Beach 1 3.2y
- 5Monticello 3.2y
Slowest
- 1Oyster Creek 26.6y
- 2Palisades 24y
- 3Watts Bar 1 23.1y
- 4Millstone 1 20.5y
- 5Comanche Peak 2 18.3y
Construction Permit to Commercial Operation
Fastest
- 1Humboldt Bay 3 2.7y
- 2Big Rock Point 2.8y
- 3Point Beach 1 3.4y
- 4Connecticut Yankee 3.6y
- 5Yankee Rowe 3.7y
Slowest
- 1Watts Bar 2 23.4y
- 2Watts Bar 1 23.4y
- 3Comanche Peak 2 18.6y
- 4Diablo Canyon 1 17y
- 5Comanche Peak 1 15.7y
Operating License to Commercial Operation
Fastest
- 1Indian Point 1 15d
- 2Crystal River 3 44d
- 3Palo Verde 3 44d
- 4Fort Calhoun 48d
- 5Vogtle 2 50d
Slowest
- 1Fermi 2 2.8y
- 2Fort St. Vrain 2.6y
- 3LaSalle 1 1.7y
- 4Arkansas Nuclear 2 1.6y
- 5LaCrosse 1.5y
Analysis by Date
Construction Permit Issued
Earliest
- 1Dresden 1 1956
- 2Indian Point 1 1956
- 3Fermi 1 1956
- 4Yankee Rowe 1957
- 5Elk River 1959
Most
Recent
- 1Harris 1 1978
- 2Wolf Creek 1 1977
- 3Perry 1 1977
- 4Saint Lucie 2 1977
- 5River Bend Station 1 1977
Operating License Issued
Earliest
- 1Dresden 1 1960
- 2Yankee Rowe 1960
- 3Indian Point 1 1962
- 4Humboldt Bay 3 1963
- 5Elk River 1963
Most
Recent
- 1Vogtle 3 2022
- 2Watts Bar 2 2015
- 3Watts Bar 1 1996
- 4Comanche Peak 2 1993
- 5Oyster Creek 1991
Commercial Operation Began
Earliest
- 1Dresden 1 1960
- 2Yankee Rowe 1961
- 3Indian Point 1 1962
- 4Big Rock Point 1963
- 5Humboldt Bay 3 1963
Most
Recent
- 1Watts Bar 2 1996
- 2Watts Bar 1 1996
- 3Comanche Peak 2 1993
- 4Seabrook 1 1990
- 5Comanche Peak 1 1990
License Expiration
Earliest
- 1Big Rock Point 2000
- 2Palisades 2007
- 3Connecticut Yankee 2007
- 4Maine Yankee 2008
- 5Oyster Creek 2009
Most
Recent
- 1Vogtle 3 2062
- 2Watts Bar 2 2055
- 3Peach Bottom 3 2054
- 4Peach Bottom 2 2053
- 5Turkey Point 4 2053
Thermal Efficiency
Net Electrical Output (MWe) / Licensed Thermal Power (MWt)
Top
5 Efficient Performers
-
1Wolf Creek 1
34.4%
-
2Pilgrim 1
34.3%
-
3Seabrook 1
34.3%
-
4McGuire 1
33.9%
-
5McGuire 2
33.9%
Lowest
Efficiency
-
1Big Rock Point
27.9%
-
2Hope Creek 1
30.0%
-
3Dresden 3
30.3%
-
4Palisades
30.3%
-
5Dresden 2
30.5%
Operating Reactor Containment Types
- PWR-DRYAMB 52
- BWR-MARK1 20
- PWR-ICECND 10
- BWR-MARK2 8
- PWR-DRYSUB 5
- BWR-MARK3 4
- BWR-DRYAMB 1
Notes:
1. Data Sources: Power generation data sourced from U.S. Nuclear Regulatory Commission (NRC) Daily Status Reports. Lifecycle and technical data from NRC and EIA records.
2. Capacity Factor: Calculated as (Net Generation / Net Capacity), where Net Generation is derived from daily power levels. Excludes units after their official decommissioning date.
3. B2B Runs: "Breaker-to-Breaker" refers to a continuous operating cycle between refueling outages with zero breaker trips (0% power) in between.
1. Data Sources: Power generation data sourced from U.S. Nuclear Regulatory Commission (NRC) Daily Status Reports. Lifecycle and technical data from NRC and EIA records.
2. Capacity Factor: Calculated as (Net Generation / Net Capacity), where Net Generation is derived from daily power levels. Excludes units after their official decommissioning date.
3. B2B Runs: "Breaker-to-Breaker" refers to a continuous operating cycle between refueling outages with zero breaker trips (0% power) in between.