Diablo Canyon 1 begins Fall 2026 refueling outage

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Diablo Canyon 1, Avila Beach, California.

Pacific Gas & Electric began a routine refueling outage at Diablo Canyon 1 on October 11, 2026. The 1,122-megawatt unit started the project one day earlier than its scheduled October 12 start date, targeting a 35-day duration.

Going into this project, the Westinghouse four-loop pressurized water reactor maintained an unscheduled-outage-free streak of 297 days after running about 86 percent of its typical 595-day operating cycle. Its prior 2025 capacity factor reached 88.9 percent, compared to a broader U.S. fleet capacity factor of 81.3 percent across 94 units. Operator Pacific Gas & Electric manages one other nuclear unit in the United States.

AVILA BEACH, CA. Diablo Canyon 1 came offline on Oct 11, 2026 for refueling. The published schedule had a Oct 12, 2026 start; actual is 1 day earlier than planned. Planned outage length is 35 days (back to service around Nov 16, 2026).

NukeWorker's start-date projection scores 100% accuracy for this unit.

Across the U.S. fleet of 94 commercial reactors, today's combined capacity factor is 81.3% (15 units currently refueling, 2 units in unscheduled outages), below the 81.8% baseline for this month over the past five years. At the same site, Diablo Canyon 2 is running at full power. Point Beach 1, Millstone 3, and Peach Bottom 2 also began refueling outages within the past week. With the unit offline for refueling, that takes about 898,000 homes' worth of generation off the grid.

Diablo Canyon 1 is a 1,122-MW Westinghouse 4-loop PWR operated by Pacific Gas & Electric (commercial operation since 1985). The utility operates 1 other U.S. nuclear unit. Its operating license runs through 2064 (renewed in 2026). The unit ran at a 88.9% capacity factor in 2025, a steady year.

Heading to Avila Beach, CA for outage work? Current per-diem averages $177/night lodging plus $86/day meals (total $263/day), and Unemployment Benefits are $450 weekly. See open nuclear jobs in California on NukeWorker.

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Sources: NRC Daily Reactor Power Status reports, utility-published outage schedules, and NukeWorker's projections.