ERCOT Storm Prep: How Solar + Battery Protects Texas Homes

Winter Storm Uri (2021), Hurricane Beryl (2024), and the May 2024 derecho made one thing clear: ERCOT grid reliability is no longer guaranteed. Here's how a properly-sized battery system keeps your household running through the next outage.

What a battery actually backs up

The size of your battery determines which loads stay online. A single Tesla Powerwall 3 (13.5 kWh usable) can typically support: refrigerator + freezer, internet + networking, lighting, phone charging, ceiling fans, and a small window A/C or mini-split — for roughly 12-24 hours depending on usage.

Central A/C during outages

Running central A/C during an outage requires 2-3 Powerwalls or equivalent. For Texas summer outages, most households step up to a 2-battery system so that at least one A/C zone stays online.

Solar + battery beats generator

Unlike a gas generator, a solar-charged battery recharges itself every sunny day. In multi-day outages (Beryl's aftermath lasted 10+ days for many Houston neighborhoods), battery + rooftop solar is the only residential backup source that keeps producing indefinitely.