Oconee 2

Online · 100% power

Duke Energy·Seneca, SC·PWR·865 MWe

Reactor Status Timeline

Online NRC data, Mon to Fri ? Actual daily reactor status from NRC reports (Mon to Fri) and the current state. What is coming -- the utility's published Scheduled outage and NukeWorker's model Projection -- is part of a subscription. Colored by status. How far ahead you can see depends on your plan.
Nov2025DecJan2026FebMarAprMayJunJulAugSepOctCoastdown: Oct 10, 2025 to Oct 27, 2025Refueling Outage (2EOC32): Oct 28, 2025 to Nov 25, 20252EOC32Power Ascension: Nov 26, 2025 to Nov 27, 2025Online: Nov 28, 2025 to Oct 10, 2026Today
OnlineCoastdownPower AscensionRefueling Outage
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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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Days of continuous operation since the last outage ended. Clean run (no forced outages since last refueling).
319
Current Run
days ✔
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Longest recorded period of continuous operation between outages (2015-11-11 to 2017-10-28).
717
Record Run
days
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Breaker-to-Breaker runs — continuous operation exceeding the cycle-adjusted threshold set for this unit with no trips to 0% power.
5
B2B Runs
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Lifetime capacity factor: average power level across all recorded days (100% = always at full power).
92.8%
Capacity Factor
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Net electricity actually generated over the most recent 12 months reported by the U.S. EIA (Form EIA-923), summed across every unit at this plant. Authoritative actuals, not an estimate.
21.95 TWh
Net Generation
EIA-923 · 12 mo to 2026-07 · plant total
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Total number of scheduled refueling outages detected in the historical data.
16
Outages
since 1999
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Average time from first power generation (>0%) to sustained full power (≥95% for 2+ days) across the last 3 scheduled outages. Click to compare against the fleet on the Operator Efficiency Leaderboard.
3
Avg Startup
days (last 3)
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Average fuel utilization — percent of the designed fuel cycle that this unit consumes before refueling, derived from the historical burn-down trajectory. Higher = more efficient operator (refuels with less margin remaining; closer to coastdown). Computed as 100% minus the unit's average refuel-point fuel %, using the last 3 years where available, otherwise lifetime average. Click to compare against the fleet on the Operator Efficiency Leaderboard.
100.0%
Fuel Utilization
3yr avg

Reactor Status

Capacity Factor (365-Day)

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100%
Current
91.2%
365-Day Avg
#47
of 94 plants
Min: 0% Max: 100% 31 days <80%

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 2 has spent 606 days in scheduled refueling outages and 49 days in forced or unplanned outages. Taller bars mark the years with the most downtime.
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Duration of each outage in days, shown chronologically. Green bars are scheduled refueling outages, red bars are forced/unscheduled. The orange dashed line marks the average duration. Extended outages (>180 days) and D&D periods are excluded.

Outage Duration Trend

Oconee 2 has 29 outages plotted here, averaging 23 days each. The most recent, in Oct 2025, was a scheduled refueling outage lasting 29 days.
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Scheduled refueling outage durations over time. Green bars are at or below this unit's average, amber up to 30% above it, red beyond that. The dashed line is the average. Shorter outages mean better execution.

Refueling Duration Trend

Oconee 2 has completed 16 scheduled refueling outages on record, averaging 38 days each. The most recent, in Oct 2025, ran 29 days.
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Time in days from first power generation (>0%) to sustained full power (≥95% for 2+ consecutive days) after each scheduled refueling outage. The dashed line marks the average. Includes startup testing holds and power dips.

Startup Duration Trend

After a refueling outage, Oconee 2 takes about 3 days to climb from first power back to full power. That average is drawn from 16 startups on record, and the most recent took 2 days.
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Estimated fuel remaining in the current cycle, expressed as a percentage of the unit's typical cycle. Starts at 100% when the unit returns to power post-refuel and drops as full-power-days are burned. Days at reduced power burn fuel proportionally — so a unit with significant downtime (high burn deficit) drops slower and ends up with MORE fuel left than its calendar position would suggest. Coastdown threshold around 15%. Toggle to overlay past cycles on a normalized "days into cycle" axis to see how aggressively this unit historically burns down before refuel.

Fuel Burn Down Cycle since Nov 26, 2025

54.8% remaining 0.3 FPD margin
Oconee 2 has an estimated 54.8% of its fuel left. Across its last 15 cycles, it has refueled with an average of 16.7% remaining.
Avg refuel: 16.7% Avg refuel (3yr): 0.0% Deepest burn: 0.0% (2015-11 → 2017-10) Most margin: 31.8% (2002-11 → 2004-03)
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Monthly capacity factor with outage events overlaid as red bands. Green bars show average power level per month. Toggle to Daily view for raw daily data.

Power History

Over its operating life, Oconee 2 has run at about 92.8% of its rated capacity. Across the last 12 reported months it averaged 92.7%. On the chart, green stretches near the top are full-power running, amber marks reduced power (50 to 89%), and red drops toward zero are outages.

Outage History & Daily Power Log

This table logs every recorded outage for Oconee 2, 29 in all since 1999. Of those, 16 were scheduled refueling outages and 13 were unplanned or forced. The typical outage lasted about 23 days. Where the Scheduled column shows (Model), the date is a NukeWorker projection because the utility had not published one.
Scheduled 2EOC32
2025-10-28 2025-11-25 29 707d 2025-11-01 -4d
Scheduled 2EOC31
2023-10-28 2023-11-21 25 609d 2023-10-28 0d
Scram # 55733 Auto
2022-02-05 2022-02-26 22 55d - -
Scram # 55638 Auto
2021-12-10 2021-12-12 3 3d - -
Scheduled 2EOC30
2021-11-13 2021-12-07 25 703d 2021-10-16 +28d
Scheduled 2EOC29
2019-11-09 2019-12-11 33 714d 2019-10-28 +12d
Scheduled 2EOC28
2017-10-28 2017-11-25 29 717d 2017-10-28 0d
Scheduled 2EOC27
2015-10-17 2015-11-11 26 82d 2015-10-17 0d
Unscheduled
2015-07-27 2015-07-27 1 285d - -
Unscheduled
2014-10-14 2014-10-15 2 314d - -
Scheduled 2EOC26
2013-10-12 2013-12-04 54 695d 2013-10-12 0d
Scheduled 2EOC25
2011-10-22 2011-11-17 27 507d 2011-10-22 0d
Unscheduled
2010-05-31 2010-06-02 3 2d - -
Scheduled 2EOC24
2010-04-25 2010-05-29 35 500d 2010-04-24 +1d
Scheduled 2EOC23
2008-10-25 2008-12-11 48 207d 2008-10-25 0d
Unscheduled
2008-04-01 2008-04-01 1 307d - -
Scheduled 2EOC22
2007-04-28 2007-05-30 33 70d 2007-04-27 +1d
Unscheduled
2007-02-16 2007-02-17 2 305d - -
Unscheduled
2006-04-13 2006-04-17 5 136d - -
Scheduled 2EOC21
2005-10-22 2005-11-28 38 496d 2005-10-21 +1d
Scheduled 2EOC20SGR/Major
2004-03-20 2004-06-13 86 484d 2004-03-19 +1d
Scheduled 2EOC19
2002-10-12 2002-11-22 42 501d 2002-10-12 0d
Scheduled 2EOC18
2001-04-26 2001-05-29 34 489d 2001-04-26 0d
Unscheduled
1999-12-24 1999-12-24 1 2d - -
Unscheduled
1999-12-22 1999-12-22 1 7d - -
Scheduled 2EOC17
1999-11-04 1999-12-15 42 135d 1999-11-04 0d
Unscheduled
1999-06-20 1999-06-22 3 110d - -
Unscheduled
1999-03-01 1999-03-02 2 3d - -
Unscheduled
1999-02-24 1999-02-26 3 - - -
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