Extreme heat does two things to the power grid at once: it drives demand to its highest levels of the year, and it makes equipment work harder. When demand outruns supply, grid operators ask people to cut back, and in the worst cases they turn power off in rotating blocks to keep the whole system from failing.
How heat causes outages
- Record demand: air conditioners run hardest in the late afternoon and early evening, just as solar output drops.
- Stressed equipment: transformers and lines carry less power safely when it’s hot, and some fail under the load.
- Rotating outages: if supply runs short, operators may cut power to neighborhoods in turns, often for an hour or so at a time.
What you can do
- When your utility or grid operator asks people to conserve, pre-cool your home earlier in the day and raise the thermostat during peak hours.
- Know where your nearest cooling center is.
- Check on older neighbors and anyone living alone.
- Keep phones and a power bank charged so you can get updates.
Can a battery keep my AC running?
A portable power station can run fans, a phone, Wi-Fi and a fridge for a long time, but central air conditioning needs far more energy than any portable unit stores. Use our backup battery calculator to see what your list really needs.
Get ready before the lights go out
Print our free 72-hour outage plan and checklists, then find the backup battery that can run what matters in your home.