Grid reliability · 2024 · 22 reporting utilities

Power outages in California

The utilities that reported here serve 15,232,351 customers between them, not the whole state. Weighted by customer count, they averaged 2.7 hr without power in an ordinary year and 4.8 hr once major events are counted. Each figure comes only from the filers that published it, and the counts are below.

What it means

Why there are two numbers

Across the utilities that filed both figures, major events account for 42% of the outage time California recorded once they are counted: 4.8 hr against 2.7 hr without them, a factor of 1.7×. Solar panels alone do not help during an outage, because a grid-tied array shuts down when the grid does, so riding through one is a battery question. This figure will not answer it: it is an annual average across a utility’s customers, not the length or the load of any single outage. What it does say is how much of the outage time here arrives with major events rather than on ordinary days.

The comparison is drawn from the 20 utilities that filed both figures of the 22 reporting here, so both sides of the ratio describe the same set of customers. The two headline figures above are averaged over everyone who filed each one, so dividing them would not give this number.

Ordinary year2.7 hr12 of 51 jurisdictions, longest first · 21 filings

With major events4.8 hrStorms, ice, and fires included as filed · 21 filings

Interruptions a year1.2×Ordinary year; 1.4× with major events

The bill sideWhat solar offsetsRates and modelled output by utility

The utilities behind the average

Each of California’s figures is a customer-weighted average of the filings that carried that metric, not of the table as a whole: the ordinary-year average is built from 21 filings and the storm-inclusive average from 21 filings, out of 22 filings that published an outage figure at all. Those two sets are not the same utilities, so the two columns cannot be compared filer by filer. A utility that filed without publishing a metric, or whose two major-event variants contradicted each other, is absent from that metric rather than counted as zero.

Reported interruption metrics for 2024, largest utility first.
Utility	Customers	Ordinary year	With major events	Interruptions
Pacific Gas & Electric Co.	5,795,693	4.6 hr	8.5 hr	1.8×
Southern California Edison Co	5,316,264	100 min	2.6 hr	0.9×
Los Angeles Department of Water & Power	1,563,515	111 min	111 min	0.7×
San Diego Gas & Electric Co	1,527,274	71 min	2.6 hr	0.5×
Imperial Irrigation District	165,674	61 min	61 min	0.7×
Modesto Irrigation District	120,484	43 min	58 min	0.5×
City of Anaheim - (CA)	117,000	46 min	46 min	0.6×
City of Riverside - (CA)	113,373	77 min	77 min	0.6×
Turlock Irrigation District	90,557	49 min	74 min	0.5×
City of Pasadena - (CA)	66,608	43 min	43 min	0.5×
City of Santa Clara - (CA)	60,620	2.7 hr	3.5 hr	0.8×
Liberty Utilities	50,151	8.3 hr	12 hr	2.4×
City of Redding - (CA)	47,176	34 min	34 min	0.3×
PacifiCorp	47,083	3.3 hr	9.8 hr	1.9×
Alameda Municipal Power	37,072	55 min	55 min	0.9×
City of Palo Alto - (CA)	30,183	not reported	2.2 hr	not reported
City of Lodi - (CA)	25,940	17 min	17 min	0.3×
Bear Valley Electric Service	24,837	64 min	101 min	0.8×
City of Azusa	17,461	11 min	not reported	0.1×
City of Moreno Valley - (CA)	8,944	45 min	45 min	0.4×
City of Shasta Lake - (CA)	4,597	77 min	77 min	not reported
City of Corona - (CA)	1,845	0 min	0 min	0.0×

What this page is not

It is a state average of utility filings, not a measurement at any address. Each filing is itself an average over a whole service territory, so a rural feeder and a downtown network arrive here as one number, and nothing in this dataset says how far an individual address sits from it. Nothing here predicts a future year either, and a single severe storm can move a utility’s figure by an order of magnitude.

The methodology page states the sources, the definitions, and the limits. Back to the Grid Reliability Index

Source: U.S. Energy Information Administration, Form EIA-861 reliability file, data year 2024, covering 2024-01-01 through 2024-12-31. The snapshot covers no later period.