DIABLO CANYON
OperatingNuclear power plant
- Capacity
- 2,323 MW
- Primary fuel
- Nuclear
- County
- San Luis Obispo County
- Operator
- PACIFIC GAS & ELECTRIC CO
- Status
- Operating
- Commissioned
- 1985
- EIA plant ID
- 6099
- Generators
- 2
- Technology
- Nuclear
- Net generation (2024)
- 18,379 GWh
- Capacity factor (2024, EIA nameplate)
- 90%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 35.2115, -120.8555
DIABLO CANYON, a 2,323 MW Nuclear power plant in San Luis Obispo County, California. Operated by PACIFIC GAS & ELECTRIC CO, commissioned 1985.
How DIABLO CANYON compares
With 2,323 MW of capacity, DIABLO CANYON ranks 2nd among the 874 operating power plants Bywatts maps in California. It accounts for about 3.2% of all operating capacity in California. Nationally it is the 14th-largest of the 55 operating Nuclear plants in the database. Commissioned in 1985, it is older than 75% of the 859 operating California plants with a recorded commissioning year. Its operator, PACIFIC GAS & ELECTRIC CO, runs 71 operating plants in California totaling 7,904 MW. It shares San Luis Obispo County with 5 other operating plants, including TOPAZ SOLAR FARM and CALIFORNIA VALLEY SOLAR RANCH.
EIA-860 lists 2 generators at the site with 2,323 MW of nameplate capacity, all nuclear technology. Net generation was 18,379 GWh in 2024 (a 90% capacity factor), up 4% from 2022. Its generators came online between 1985 and 1986.
Grid neighborhood
The nearest named substation is PECHO VALLEY, about 0.4 miles away; the closest transmission line found within 10 miles is a 230 kV line owned by PACIFIC GAS & ELECTRIC COMPANY, about 0.5 miles away. Another 2 operating power plants totaling 3 MW sit within 25 miles; the largest is COLD CANYON 1 (2 MW, Biomass).
Computed by Bywatts from HIFLD power plant, substation and transmission line records and EIA-860/923 survey data; distances are straight-line. Sources and methodology
Weather peril exposure
DIABLO CANYON is a 2,323 MW nuclear power plant in San Luis Obispo County, CA, operated by PACIFIC GAS & ELECTRIC CO, commissioned in 1985. San Luis Obispo County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.5 of 5 at the 12th national percentile. Wildfire is the leading peril, rated Relatively High by FEMA at the 96th percentile.
The Bywatts loss layer is calibrated to solar PV hardware, so it is not applied to a nuclear plant. The ratings below are the FEMA National Risk Index county hazard ratings for this location.
San Luis Obispo County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Wildfire | Relatively High | 96th | 4.9 of 5 | <0.01 |
| Earthquake | Relatively Moderate | 95th | 4.8 of 5 | 0.11 |
| Riverine flooding | Relatively High | 91st | 4.6 of 5 | 0.64 |
| Heat wave | Relatively Low | 77th | 4.1 of 5 | 8.5 |
| Coastal flooding | Relatively Low | 28th | 2.1 of 5 | 3.1 |
| Tornado | Very Low | 2nd | 1.1 of 5 | 0.09 |
| Strong wind | Very Low | 1st | 1.1 of 5 | 0.02 |
| Lightning | Relatively Low | 1st | 1.0 of 5 | 3.2 |
| Winter weather | Very Low | 1st | 1.0 of 5 | 1.1 |
| Hail | Very Low | 0th | 1.0 of 5 | 0.05 |
Perils not assessed in San Luis Obispo County
These perils carry no usable National Risk Index figure for this county, so they are excluded from the scoring rather than scored zero. A zero would claim the peril was assessed and found benign.
| Peril | Why it is not scored |
|---|---|
| Hurricane | FEMA rating is "Not Applicable" for this county |
| Ice storm | FEMA rating is "Not Applicable" for this county |
Model hail, wind and flood exposure for San Luis Obispo County in the weather risk calculator
Ratings are the FEMA National Risk Index county hazard ratings; the peril score is a Bywatts transform of the FEMA national percentile. Full data sources and the solar vulnerability methodology are in the weather risk calculator.
Modeled estimate for screening and negotiation. Built from FEMA National Risk Index county hazard data and a solar vulnerability layer documented above. Not a quote, a binder, or actuarial advice, and not a substitute for a carrier's own model. Hazard data: FEMA National Risk Index December 2025, synced 2026-07-24. Resolution is county level, not site level.