Power Outages in California: Duration, Frequency & Backup Planning
California’s all-event SAIDI was below the U.S. total in 2024 but still materially above its no-major-event value, making major-event context important in a very large backup-power market.
Source: U.S. Energy Information Administration, Electric Power Annual Table 11.3.
4.7 hours
279.6 minutes of all-event SAIDI per average customer in 2024. Rank: #26 of 51 jurisdictions by duration.
1.34 events
Average non-momentary interruptions per customer. Rank: #27 by SAIFI.
208 minutes
Average restoration duration per sustained interruption using EIA’s all-event CAIDI.
How much did major events change California’s 2024 result?
EIA publishes reliability both with all events and with major-event days excluded. We calculate the difference between those two SAIDI values.
Without major events, California’s SAIDI was about 2.6 hours. The all-event figure was 4.7 hours. This does not mean every household experienced that amount of downtime; SAIDI is a statewide utility-weighted average across reporting customers.
How California compared with the national total
California’s all-event SAIDI was 54% lower than the U.S. total of 611.3 minutes in the same EIA table.
Its SAIFI was 12% lower than the U.S. total of 1.521 sustained interruptions per customer.
National all-event CAIDI was 401.9 minutes per interruption versus 208.0 minutes in California.
California buyers should size from their own critical-load profile and local utility experience rather than assuming the statewide average represents wildfire, public-safety shutoff or neighborhood-level exposure.
Do not size a battery from SAIDI alone
SAIDI is useful context, but it is not a recommended battery runtime. A home backup system should be sized from the loads you actually need, the outage duration you want to cover and the recharge paths you can depend on.
California reliability snapshot
“Without major events” values remove major-event days under the reporting utility’s applicable method.
| Metric | All events | Without major events | What it means |
|---|---|---|---|
| SAIDI | 279.6 min | 158.2 min | Annual sustained-interruption minutes per average customer |
| SAIFI | 1.345 | 1.154 | Sustained interruptions per average customer |
| CAIDI | 208.0 min | 137.1 min | Average restoration minutes per sustained interruption |
EIA reported customer coverage for California: 100.0%. EIA notes percentages may occasionally exceed 100% because reliability-meter counts and customer-count denominators come from different survey schedules.
What this report can tell you
It shows the statewide scale of sustained distribution interruptions in one calendar year, separates major-event and non-major-event reporting, and makes it easier to compare California with the national benchmark and other states.
It is useful for understanding why a backup plan needs both stored energy and a realistic recharge strategy.
What it cannot tell you
It cannot predict the next outage at a specific address. Utility territory, feeder design, vegetation, weather, local construction and restoration priorities can produce reliability very different from the statewide average.
Use the state reliability explorer to compare other states and the national study for methodology and full rankings.