Oconee 1 — Nuclear Reactor Data & Live Status

Live reactor status, daily power data, outage history & performance charts, scram history, capacity factor & statistics, community ratings, technical specifications, NRC licensing data, photos, nearby jobs, satellite map, contact information, and per diem rates for Oconee 1.

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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.
85
Excellence
#6 of 93
Top Quartile
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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.
614
Current Run
days
#4 of 95
Top Quartile
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Longest recorded period of continuous operation between outages.
711
Record Run
days
#33 of 95
Mid Quartile
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Breaker-to-Breaker runs — continuous operation exceeding the cycle-adjusted threshold (612 days for this 24-month cycle unit) with no trips to 0% power.
3
B2B Runs
100% toward B2B (611/612d)
#69 of 86
Bottom 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.
90.9%
Capacity Factor
#35 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), summed across every unit at this plant. These are authoritative actuals, not an estimate.
22.48 TWh
Net Generation
EIA-923 · 12 mo to 2026-04 · plant total
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Community rating score (Bayesian-adjusted). Based on 1 vote. Ranked against all rated facilities.
52.3
Rating
1 vote
#50 of 97
Mid Quartile
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Total NRC-reported scram events (emergency reactor shutdowns). Ranked fleet-wide — fewer scrams = better rank.
3
Scrams
#9 of 94
Top Quartile
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Years since commercial operation began. License remaining: 26.6 years.
53
Operating Age
years
26.6 yrs remaining

Reactor Status Timeline

Online NRC data, Mon to Fri ? Actual daily reactor status from NRC reports (Mon to Fri), the current state, and what is coming: the utility's published Scheduled outage plus, for subscribers, NukeWorker's model Projection. Colored by status. How far ahead you can see depends on your plan.
Aug2025OctDecFebAprJunAugOctDecOnline: Jul 19, 2025 to Jul 19, 2026Scheduled Outage (Scheduled): Oct 24, 2026, about 29 daysScheduledToday
OnlineScheduled (published)
Full history & analysis →
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Composite Operational Excellence Score for Oconee 1 — 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 6 of 93

NukeWorker scores Oconee 1's operational excellence at 85 out of 100 over the past five years, ranking it 6 of 93 reactors in the active US fleet. The score blends reliability, efficiency, and operating discipline drawn from public performance data.
Time window
NukeWorker's
Operational
Excellence Score
85/100
Top Quartile · #6/93
5-year window

Oconee 1 ranks #6 of 93 active US units on NukeWorker's Operational Excellence Score over the 5-year window. Strongest area: Capacity Factor (100th percentile). Weakest: Refuel Duration (73th percentile).

Reliability
92
Capacity factor + Forced outages + B2B streaks
Efficiency
73
Fuel utilization + Refuel duration
Discipline
90
Startup duration + Scram count
Cohort Rankings apples-to-apples comparison within each peer group
Reactor type: #3 of 61 PWR
Containment: #3 of 47 Dry Ambient (PWR)
Cycle length: #4 of 40 24-month cycle
Fleet rank above (6 of 93) compares all active US units; cohort ranks compare only against units sharing this property.
Per-dimension breakdown (7 metrics)
Capacity Factor 100th
97.7% (higher better, Reliability)
Forced Outage Days/yr 98th
0.4d (lower better, Reliability)
B2B Avg Streak 79th
695d (higher better, Reliability)
Refuel Duration 73th
26d (lower better, Efficiency)
Scrams (5-year) 90th
0.0/yr (lower better, Discipline)

Each dimension's percentile is computed across the active US fleet (93 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 93 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: 2021: 52/100 (#51/93)2022: 64/100 (#25/92)2023: 77/100 (#14/92)2024: 84/100 (#9/93)2025: 84/100 (#9/93)2026: 86/100 (#6/93) Stable vs 2025
Compare Oconee 1 head-to-head with up to 3 other units. Compare now

Capacity Factor (365-Day)

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100%
Current
100%
365-Day Avg
#2
of 94 plants
Min: 100% Max: 100% 0 days <80%
B2B CHAMPION
2,778 days without a trip  ·  3 Career Runs  · 3 since last trip
Champion since Aug 12, 2020

Outage Duration Trend

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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.
Oconee 1 has completed 16 scheduled refueling outages on record, averaging 44 days each. The most recent, in Oct 2024, ran 22 days.

Power History (12-Month)

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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.
Over the past 12 months Oconee 1 has run at an average of 100% of rated power. On the chart, green stretches are full-power running and dips toward zero mark reduced output or outages.

Outage Days by Year

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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.
Across its recorded history, Oconee 1 has spent 700 days in scheduled refueling outages and 128 days in forced or unplanned outages. Taller bars mark the years with the most downtime.

Facility Statistics

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Key performance and lifecycle metrics calculated from NRC operational data. Includes operating age, construction timeline, capacity factor, efficiency, generation totals, and reliability records.
Oconee 1 has operated for about 53 years and averaged a 90.9% lifetime capacity factor, generating roughly 187.6 TWh of electricity. Its longest unbroken run reached 711 days.
Lifecycle & Tenure
Operating Age: 53 Yrs
Build Time: 5.7 Yrs
Lic. Remaining: 26.6 Yrs
Production & Power
Lifetime CF: 90.9%
Efficiency: 33%
Generated: 187.6 TWh
Reliability & Outages
Record Run: 711 Days
Refuelings: 16
Avg Startup: 4.1 Days

Location & Contact

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Physical address, phone number, and website for this facility. Use the directions link to get driving directions via Google Maps.
Address:
155 East Pickens Highway
Seneca, SC 29672, USA
Get Directions
Phone: (864) 885-3000

Per Diem Rates FY 2026

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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, SC

Unemployment Benefits SC

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Maximum state unemployment insurance benefits for SC. Actual benefits depend on your earnings history and may be lower than the maximum. Data as of Jan 2026.
$326
Max Weekly
20
Max Weeks
$6,520
Max Total
7-day waiting period before benefits begin

Ownership & Construction

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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.
Owner/Operator: Duke Energy
Architect Engineer: DBDB
Constructor: DUKE

Technical Specs

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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: B&W LLP
Thermal Power: 2610 MWt
Net Capacity: 862 MWe
Efficiency: 33%
Status: Operating

Licensing

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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 #: 05000269
License #: DPR-38
License Type: OL-FP
Const. Permit: 1967-11-06
Operating Lic: 1973-02-06
Commercial Op: 1973-07-15
License Renewed: 2025-03-31
License Exp: 2053-02-06

Market & Region

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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: SAT — South Atlantic
Balancing Authority: DUK — Duke Energy Carolinas
Market Structure: Regulated — Rate-regulated utility (cost-of-service pricing)