Clinton
Online · 100% powerConstellation Energy·Clinton, IL·BWR·1,079 MWe
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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.
Excellence
Rank locked · 93 units
Subscribers
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Current reactor power level from the most recent NRC daily report.
100%
Power
ONLINE
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Days of continuous operation since the last outage ended. Ranked against all operating units.
358
Current Run
days
#13 of 95
Top Quartile
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Longest recorded period of continuous operation between outages.
712
Record Run
days
#34 of 95
Mid Quartile
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Breaker-to-Breaker runs — continuous operation exceeding the cycle-adjusted threshold (626 days for this 24-month cycle unit) with no trips to 0% power.
3
B2B Runs
#64 of 86
Mid Quartile
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Lifetime capacity factor: average power level across all recorded days (100% = always at full power). Ranked against all NRC-tracked units.
89.2%
Capacity Factor
#58 of 95
Mid Quartile
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Net electricity actually generated over the most recent 12 months reported by the U.S. Energy Information Administration (Form EIA-923). These are authoritative actuals, not an estimate.
8.36 TWh
Net Generation
EIA-923 · 12 mo to 2026-07
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Total NRC-reported scram events (emergency reactor shutdowns). Ranked fleet-wide — fewer scrams = better rank.
14
Scrams
#85 of 94
Bottom Quartile
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Years since commercial operation began. License remaining: 20.5 years.
38.9
Operating Age
years
20.5 yrs remaining
Excellence Score, Records & Plant Facts
Breaker-to-Breaker Runs 3 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.
Clinton has logged 3 breaker-to-breaker runs, continuous stretches from one refueling to the next with no trip to zero power. Its longest ran 711 days, and its runs average 691 days.
711
Best Run (days)
C1R19 (2019-10-17) → C1R20 (2021-09-27)
691
Avg Run (days)
All Runs
| 2023-10-09 | 2025-09-08 | 700 days | C1R21 → C1R22 |
| 2019-10-17 | 2021-09-27 | 711 days | C1R19 → C1R20 |
| 2010-02-05 | 2011-11-30 | 663 days | C1R12 → C1R13 |
About This Site
Written by NukeWorker from public records: facts that do not change. Operator, status and capacity come from the live data elsewhere on this page. Sources: Wikipedia: Clinton Nuclear Generating Station.
Clinton Power Station is a single-unit nuclear plant in Harp Township, DeWitt County, Illinois, near the city of Clinton. It is cooled by Clinton Lake, an artificial lake fed by Salt Creek.
Read more
Illinois Power began construction on October 1, 1975, and the plant uses a General Electric BWR-6 boiling water reactor with Mark 3 containment. The operating license was issued on April 17, 1987, the reactor was connected to the grid on April 24, 1987, and commercial operation began on November 24, 1987. A planned second unit was cancelled. In 1996 Illinois Power shut the plant down after technical problems and safety violations, and it stayed idle for about three years.
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.
Clinton has operated for about 38.9 years and averaged a 89.2% lifetime capacity factor, generating roughly 230.3 TWh of electricity. Its longest unbroken run reached 712 days.
Lifecycle & Tenure
Operating Age: 38.9 Yrs
Build Time: 11.7 Yrs
Lic. Remaining: 20.5 Yrs
Production & Power
Lifetime CF: 89.2%
Efficiency: 31.1%
Generated: 230.3 TWh
Reliability & Outages
Record Run: 712 Days
Refuelings: 17
Avg Startup: 11 Days
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.
Ownership, operation and management history
| Date | Change | From | To |
|---|---|---|---|
| Dec 16, 1999 | Sold | Illinois Power | AmerGen (PECO Energy / British Energy) |
| Dec 22, 2003 | Ownership stake | AmerGen (Exelon / British Energy) | AmerGen (wholly owned by Exelon) |
| Jan 2009 | Merger | AmerGen | Exelon |
| Feb 1, 2022 | Spin-off | Exelon | Constellation Energy |
CEG
Constellation Energy Corporation
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258.84
Day's Range
263.12 – 273.21
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228.63 – 406.04
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2,785,585
Delayed quote as of Oct 21, 2026 4:00 PM ET.
Source: Yahoo Finance.
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Operational Excellence Score Subscribers
Clinton is rated 0 to 100 on how well it actually runs, scored against every other operating reactor in the US fleet from its own operating record. Subscribers see the score, the three sub-scores behind it, and each of the seven measured inputs.
- This unit's composite score and fleet rank
- Reliability, Efficiency and Discipline sub-scores
- All seven measured inputs, with fleet percentiles
- Rank against comparable units, not just the fleet
- Three-year, five-year and lifetime windows
- Five-year trend, and every other operating US reactor
Included with every outage subscription and with NukeWorker Gold membership. Trading the outage rather than working it? The same record, cut by power market, is on NukeGryd.
Scram History 14 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.
Clinton has recorded 14 reactor scrams, or emergency shutdowns, since 2011 (7 automatic, 7 manual). On average the unit was back to full power about 9.1 days after each trip.
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:
BWR
Containment:
BWR-MARK 3
NSS Supplier:
GE 6
Turbine Supplier:
GENERAL ELECTRIC CO. IAEA
Thermal Power:
3473 MWt
Net Capacity:
1079 MWe
Gross Capacity:
1,098 MWe IAEA
Design Capacity:
950 MWe IAEA
Efficiency:
31.1%
Status:
Operating
Lifetime Output:
265.7 TWh through 2025 IAEA
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 #:
05000461
License #:
NPF-62
License Type:
OL-FP
Const. Permit:
1976-02-24
Construction Start:
1975-10-01 IAEA
Operating Lic:
1987-04-17
First Criticality:
1987-02-27 IAEA
Grid Connection:
1987-04-24 IAEA
Commercial Op:
1987-11-24
License Renewed:
2025-12-16
License Exp:
2047-04-17
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:
ENC
— East North Central
Balancing Authority:
MISO
— Midcontinent Independent System Operator (ISO/RTO)
Market Structure:
Merchant
— Competitive generator selling into wholesale markets