Home batteries and PSPS shutoffs: a practical guide
What a battery can really run during an outage, how long it lasts, and how to decide between essentials and whole-home backup.
DeShawn CarterService and Monitoring Manager · July 14, 2026 · 6 min read
Every fire season, thousands of foothill and rural homes in Madera, Fresno and Tulare counties get notices about Public Safety Power Shutoffs. Even in town, summer heat storms can knock out power for hours. A home battery is the quietest, cleanest way to ride through them, but only if it is sized for the loads that matter to you.
This guide walks through what a battery can realistically power, how long it lasts, and the decisions we help homeowners make before installation.
Start with your critical loads
Before talking about battery size, list what you truly need during an outage. For most households the list looks something like this.
- Refrigerator and freezer
- Lights in a few rooms
- Wi-Fi router and phone charging
- Gas furnace blower or a few ceiling fans
- Well pump on rural properties
- Medical devices such as CPAP machines or oxygen concentrators
How long will a battery last?
A single 13.5 kWh battery running only essentials, about 400 to 600 watts on average, can last 24 hours or more before solar recharges it the next morning. Central air conditioning changes that picture quickly. A 3-ton AC unit can draw 3,000 watts or more while running, which could drain the same battery in a few hours.
That is why we talk about backup in terms of what runs, not just how many kilowatt-hours you buy. With solar recharging the battery each day, a well-designed essentials system can run indefinitely through a multi-day shutoff in sunny weather.
Essentials panel or whole-home backup?
An essentials, or critical loads, panel moves your most important circuits to a sub-panel powered by the battery during outages. It is the most cost-effective approach and makes battery capacity last longer.
Whole-home backup uses a gateway that isolates your entire home from the grid. You can use any circuit, but you have to manage large loads yourself, and you may need two or more batteries. Many rural clients with well pumps and larger homes choose this option.
Well pumps need special attention
Well pumps draw a large surge of current for a split second when they start. If the battery inverter cannot deliver that surge, the pump will not start even though the battery has plenty of stored energy. We measure or look up your pump's starting current during the survey and size the system accordingly, sometimes adding a soft-start device.
Programs that may help
California's Self-Generation Incentive Program has offered battery rebates, with larger amounts for households with medical needs or those in high fire-threat districts and areas affected by repeated shutoffs. Funding changes over time and can run out, so we check current availability during your consultation and help with applications where available.
Everyday value, not just emergencies
Most days there is no outage. On those days the battery earns its keep by storing midday solar and powering your home through the expensive evening hours. You can set a backup reserve, for example keeping 30 percent charged at all times, and increase it when a red flag warning is issued.
Decide what must stay on, then size the battery around those loads. A smaller system that covers true essentials often beats a bigger one that promises everything.
This article is general information with sample figures, not financial or tax advice.
