If you're on a California utility today, chances are you're on a time-of-use (TOU) rate — where the price of electricity changes depending on the hour. Understanding how it works is the key to lowering your bill, with or without solar.
What time-of-use means
Instead of one flat price per kilowatt-hour, TOU rates charge more during "peak" hours — typically late afternoon into the evening, roughly 4 to 9 p.m., when demand across the grid is highest. Power is cheaper during off-peak hours overnight and midday. The catch: peak hours line up exactly with when most families get home, cook, and run the AC.
Why it changes the solar equation
Solar produces most of its power midday, when electricity is cheap — and least in the evening, when it's expensive. So solar alone lowers your bill, but it doesn't fully protect you from those pricey peak hours after the sun goes down. That gap is exactly where the savings opportunity lives.
How storage beats the peak
A home battery stores your cheap midday solar production and discharges it during the expensive evening peak — so you're powering your home with your own energy at the very hours the utility charges the most. For many California homes, solar plus a battery on a TOU plan is the combination that delivers the biggest, most predictable savings.
Simple moves that help even without storage
Shifting big loads — dishwasher, laundry, EV charging, pool pump — to off-peak hours can trim your bill on its own. Pre-cooling the house before peak and setting appliances on timers are easy wins while you weigh solar and storage.
Paxton Energy models your bill against your actual TOU rate so you can see exactly what solar — and solar plus storage — would save you. The assessment is free.