A Flex Alert is a public appeal issued by the California Independent System Operator asking consumers to cut electricity use voluntarily during a window, usually 4 to 9 p.m., when supply is expected to run tight. It is a demand-side emergency tool, not a rate or a rule.
How it fits the record
- California issued 26 Flex Alerts in 2001, 11 in 2022, and none from 2023 through the summer of 2026, a stretch that coincides with the state’s battery fleet growing from about half a gigawatt to more than 17 gigawatts.
- A Flex Alert is the step before rotating outages. The August 2020 heat wave went past alerts to a Stage 3 emergency and rolling blackouts.
Why it matters for parking
A Flex Alert window lands on the hours when commuters arrive home and plug in. Facilities with managed charging can drop load during an alert automatically; facilities that charge on arrival are the load the alert is trying to shed. Source: California ISO, via Los Angeles Times.