?
Composite Operational Excellence Score (0-100) — average percentile rank across 7 dimensions in three sub-scores: Reliability (capacity factor, forced outage days, B2B avg streak), Efficiency (fuel utilization, refuel duration), and Discipline (startup duration, scram count). 5-year window. Higher = more operationally excellent. Click to see the full breakdown.
28
Excellence
#81 of 94
Bottom Quartile
?
Current reactor power level from the most recent NRC daily report.
100%
Power
ONLINE
?
Days of continuous operation since the last outage ended. Ranked against all operating units.
166
Current Run
days
#47 of 95
Mid Quartile
?
Longest recorded period of continuous operation between outages.
528
Record Run
days
#89 of 95
Bottom Quartile
?
Breaker-to-Breaker runs — continuous operation exceeding the cycle-adjusted threshold (400 days for this 18-month cycle unit) with no trips to 0% power.
8
B2B Runs
#20 of 87
Top Quartile
?
Lifetime capacity factor: average power level across all recorded days (100% = always at full power). Ranked against all NRC-tracked units.
85.6%
Capacity Factor
#85 of 95
Bottom Quartile
?
Community rating score (Bayesian-adjusted). Based on 33 votes. Ranked against all rated facilities.
66.8
Rating
33 votes
#5 of 97
Top Quartile
?
Total NRC-reported scram events (emergency reactor shutdowns). Ranked fleet-wide — fewer scrams = better rank.
9
Scrams
#69 of 94
Mid Quartile
?
Years since commercial operation began. License remaining: 18.4 years.
41.4
Operating Age
years
18.4 yrs remaining
Estimated reactivity remaining in Callaway's current fuel cycle, shown as a stylized fuel rod that drains as the cycle progresses. The cycle starts when the unit returns to power after its most recent refueling outage, and the gauge represents the fraction of that cycle's typical effective full-power days (EFPD) still available. Days at less than 100% power burn fuel proportionally — so a unit with significant downtime (high burn deficit) drains slower and ends with MORE reactivity left, giving operators margin to coast down (extend the cycle by reducing power) instead of refueling on the calendar. The dashed red line near the bottom marks the rough industry coastdown threshold (~15% remaining). Cycle target is the unit's median recent cycle length. Source: NRC daily reactor status reports cross-referenced against scheduled refuel outage history.
Fuel Burn Down Cycle since Jul 8, 2025
Fresh — 100%
Refuel — 0%
40.6% remaining
Mid-cycle
Cycle progress
309 / 487 days
EFPD remaining
198 days
Effective burn
289 EFPD
Burn deficit
19.7 FPD
Callaway is mid-cycle with healthy reactivity. Operators have flexibility to defer or advance the next refuel as needed.
This unit has accumulated 19.7 FPD of unburned fuel from cycle downtime — that's free margin to extend the cycle if operators want.
This unit has accumulated 19.7 FPD of unburned fuel from cycle downtime — that's free margin to extend the cycle if operators want.
Historical Burn-Down (17 completed cycles)
Avg refuel point
4.7% remaining
Avg refuel (3yr)
0.0% remaining
Deepest burn
0.0% (1999-11 → 2001-04)
Most margin
51.4% (2020-12 → 2022-04)
Last 5 cycles at refuel
5%
2017-12
0%
2019-05
51%
2020-12
3%
2022-05
0%
2023-11
~2% coastdown (this unit)
Composite Operational Excellence Score for Callaway — average percentile rank across 7 publicly observable metrics in three sub-scores: Reliability (capacity factor, forced outage days, B2B avg streak), Efficiency (fuel utilization, refuel duration), and Discipline (startup duration, scram count). Toggle the time window (3yr / 5yr / Lifetime) to see how this unit's standing shifts. Each dimension percentile-ranked across the active US fleet. Sub-score = average of components. Composite = average of the three sub-scores.
NukeWorker's Operational Excellence Score 5-yr composite · ranks 81 of 94 →
Time window
NukeWorker's
Operational
Excellence Score
Operational
Excellence Score
28/100
Bottom Quartile · #81/94
5-year window
Callaway ranks #81 of 94 active US units on NukeWorker's Operational Excellence Score over the 5-year window. Strongest area: Startup Duration (69th percentile). Weakest: B2B Avg Streak (2th percentile).
Reliability
5
Capacity factor + Forced outages + B2B streaks
Efficiency
22
Fuel utilization + Refuel duration
Discipline
58
Startup duration + Scram count
Cohort Rankings
apples-to-apples comparison within each peer group
Reactor type:
#56 of 61
PWR
Containment:
#45 of 48
Dry Ambient (PWR)
Cycle length:
#48 of 54
18-month cycle
Fleet rank above (81 of 94) compares all active US units; cohort ranks compare only against units sharing this property.
Per-dimension breakdown (7 metrics)
Capacity Factor
8th
79.1% (higher better, Reliability)
Forced Outage Days/yr
5th
24.0d (lower better, Reliability)
B2B Avg Streak
2th
467d (higher better, Reliability)
Fuel Utilization
38th
97.5% (higher better, Efficiency)
Refuel Duration
6th
54d (lower better, Efficiency)
Startup Duration
69th
3.7d (lower better, Discipline)
Scrams (5-year)
48th
0.4/yr (lower better, Discipline)
Each dimension's percentile is computed across the active US fleet (94 units with sufficient history). Sub-score = average of its component percentiles. Composite = average of the three sub-scores. 5-year window. View full leaderboard →
Methodology
NukeWorker's Operational Excellence Score is a composite ranking that combines 7 publicly observable performance metrics into a single 0-100 number per US nuclear unit.
How it's computed: Each unit's raw value is converted to a percentile (0-100) within the 94 active US units that have at least 2 completed refueling cycles. The 7 percentiles are averaged into 3 sub-scores (Reliability, Efficiency, Discipline), and those are averaged into the final composite.
Active window — 5-year:
- Reliability — Capacity factor (5yr), forced outage days/yr (5yr), B2B avg streak (lifetime)
- Efficiency — in-cycle fuel utilization (3yr), median refuel duration (5yr)
- Discipline — robust mean startup duration, scrams/yr (5yr, annualised)
Cohort rankings: alongside the fleet rank, each unit gets ranked within its reactor type (PWR/BWR), containment design (Ice Condenser, Mark I, etc.), and cycle length (12/18/24-month). Useful for apples-to-apples comparisons.
What's excluded: subjective community ratings, confidential INPO ratings, financial metrics. We only use publicly available NRC + cycle data.
Why three windows? 5yr (default) is the industry standard. 3yr captures recent operational changes and post-pandemic recovery. Lifetime gives newer units a fair comparison and reveals long-term consistency.
Edge cases: units with fewer than 2 cycles (e.g., Vogtle 4) show "Provisional". Decommissioned units excluded.
Refresh cadence: recomputed daily. Each window cached separately.
A data-derived proxy for operational performance; not affiliated with INPO. INPO ratings are confidential and qualitative — ours is public and quantitative.
5-yr trend:
Stable vs 2025
Compare Callaway head-to-head with up to 3 other units.
Compare now
Capacity Factor (365-Day)
100%
Current
79.4%
365-Day Avg
#66
of 94 plants
Min: 0%
Max: 100%
78 days <80%
Breaker-to-Breaker Runs 8 runs
Breaker-to-breaker runs measure continuous operation between refueling outages using a cycle-adjusted threshold (90% of cycle length minus RFO duration). An active streak means the unit has been running continuously since the last refueling with no trips to 0% power.
521
Best Run (days)
2007-05-09 → 2008-10-11
467
Avg Run (days)
All Runs
| 2024-02-19 | 2025-03-29 | 404 days |
| 2017-12-18 | 2019-04-01 | 469 days |
| 2016-05-10 | 2017-10-07 | 515 days |
| 2013-08-17 | 2014-10-12 | 421 days |
| 2011-11-25 | 2013-04-09 | 501 days |
| 2010-06-12 | 2011-10-16 | 491 days |
| 2009-03-02 | 2010-04-18 | 412 days |
| 2007-05-09 | 2008-10-11 | 521 days |
Scram History 9 events since 2011
Automatic and manual reactor scram (emergency shutdown) events reported to the NRC since 2011. Includes event dates, trip type, and average recovery time. Click the title to view the full fleet scram dashboard.
Outage Duration Trend
?Scheduled refueling outage durations over time. Green bars are below average, yellow near average, red above. Dashed line shows the plant's historical average. Shorter outages mean better execution.
Power History (12-Month)
?Daily power output as a percentage of rated capacity over the past 365 days. Green segments indicate full power (90%+), yellow shows reduced output, and red indicates significant power reductions or shutdowns.
Outage Days by Year
?Total days spent in outage each year, split by scheduled refueling (blue) and forced/unplanned (red). Lower totals indicate better reliability and outage execution. Hover for details.
Facility Statistics
Key performance and lifecycle metrics calculated from NRC operational data. Includes operating age, construction timeline, capacity factor, efficiency, generation totals, and reliability records.
Lifecycle & Tenure
Operating Age: 41.4 Yrs
Build Time: 8.7 Yrs
Lic. Remaining: 18.4 Yrs
Production & Power
Lifetime CF: 85.6%
Efficiency: 33.4%
Generated: 244.2 TWh
Reliability & Outages
Record Run: 528 Days
Refuelings: 18
Avg Startup: 4.3 Days
NukeWorker Member Ratings 33 votes
Community ratings from NukeWorker members. Vote to share your experience working at this facility. Score uses a Bayesian average that accounts for vote count — facilities with few votes are pulled toward the fleet average, so rankings reflect confidence, not just raw percentages.
Above Average
23 (69%)
Average
8 (24%)
Below Average
2 (6%)
Facility Map
Interactive satellite map showing the facility's geographic location. Marker color indicates current status: green for online, red for offline, orange for reduced power. Click the header to open in Google Maps satellite view.
38.7594, -91.7855
Location & Contact
Physical address, phone number, and website for this facility. Use the directions link to get driving directions via Google Maps.
Phone:
(573) 676-8000
Website:
http://www.ameren.com/
Per Diem Rates FY 2026
Per diem covers lodging and meals & incidental expenses (M&IE) for government and contractor travel near this facility. Rates are from GSA for FY 2026.
$110
Lodging/Night
$68
M&IE/Day
$178
Total/Day
Standard Rate, MO
Unemployment Benefits MO
Maximum state unemployment insurance benefits for MO. Actual benefits depend on your earnings history and may be lower than the maximum. Data as of Jan 2026.
$320
Max Weekly
20
Max Weeks
$6,400
Max Total
7-day waiting period before benefits begin
Jobs in MO 23 active
Active nuclear industry job listings in MO from the NukeWorker job board. Click a job title for full details, or click the header to search all jobs in this state.
Photos
Photos of this facility from the NukeWorker photo gallery. Click the header or any photo to browse the full album.
Ownership & Construction
The utility or company that owns and operates the facility, the architect-engineer responsible for plant design, and the primary construction contractor. Click names to view all facilities by that entity on the map.
Technical Specs
Reactor design specifications including type (PWR/BWR), containment design, nuclear steam supply system manufacturer, thermal and electrical power ratings, and current operational status.
Reactor Type:
PWR
Containment:
PWR-DRYAMB
NSS Supplier:
WEST 4LP
Thermal Power:
3565 MWt
Net Capacity:
1190 MWe
Efficiency:
33.4%
Status:
Operating
Licensing
NRC licensing history including docket number, license type and number, construction permit date, operating license issuance, commercial operation date, license renewal, and expiration date.
Docket #:
05000483
License #:
NPF-30
License Type:
OL-FP
Const. Permit:
1976-04-16
Operating Lic:
1984-10-18
Commercial Op:
1984-12-19
License Renewed:
2015-03-06
License Exp:
2044-10-18
Market & Region
EIA market and grid-region classifications: NERC reliability region, U.S. Census region, balancing authority responsible for grid operations, and whether the unit operates as a rate-regulated utility or a competitive merchant generator. Hover any value for the full name.
NERC Region:
SERC
— SERC Reliability Corporation
Census Region:
WNC
— West North Central
Balancing Authority:
MISO
— Midcontinent Independent System Operator (ISO/RTO)
Market Structure:
Regulated
— Rate-regulated utility (cost-of-service pricing)