Understanding Solar Battery Storage
A battery doesn't magically power your whole house for free. It does one specific thing well: store energy so you can use it later — including, with the right setup, during a grid outage.
Last updated 2026-08-19
Here's what a battery actually does and the terms you'll hear.
Backup power
The ability to keep selected circuits — or, in some setups, the whole home — running during a grid outage.
Stored solar electricity
Power your panels produced during the day and the battery held onto for later use.
Essential-load backup
A smaller battery setup covering only critical loads (fridge, lights, internet, well pump).
Whole-home backup
A larger setup intended to power most or all of the home during an outage.
Battery capacity
How much energy the battery holds, measured in kWh.
Power output
How much power the battery can deliver at once, measured in kW — affects which appliances it can start.
Solar + battery interaction
When sized right, solar charges the battery during the day; the battery powers the home at night or during an outage.
Grid charging
Some batteries can also charge from the grid, where permitted by your utility and rate plan.
Tesla Powerwall
The Tesla Powerwall is the most recognized home battery. Recent versions integrate solar inversion into the unit and offer high continuous output. It's well suited to whole-home backup scenarios and installations already designed around a Tesla ecosystem. Whether it's the right fit depends on your loads, budget, and incentives.
Enphase battery systems
Enphase offers modular battery systems that pair naturally with Enphase microinverters. Their modular approach lets you add capacity in increments, which can be useful if you want to start with essential-load backup and expand later.
We won't declare one universally better
Do I need a battery with solar?
No. Most grid-connected solar systems do not require a battery. Without a battery, your home uses solar during the day and pulls from the grid at night, with net metering (where available) smoothing out the difference across the year. A battery is an add-on for homeowners who want outage protection, time-of-use optimization, or greater self-consumption — not a requirement.
Will solar work during an outage without a battery?
Generally no. Standard grid-tied solar shuts down when the grid goes down, for safety (see How Solar Works). Without a battery — or specifically configured backup-capable equipment — your solar won't keep your lights on during an outage.
Next step
Common questions
Curious whether a battery makes sense for your home?
Ask about battery options and how they fit your solar design.
About Charles Brogden
Charles Brogden works directly with homeowners through AllSeason Solar & Roofing, helping customers understand solar system design, equipment, roofing considerations and available solar options.
Serving homeowners throughout New Jersey and Pennsylvania.