A solar battery is worth it if you want power during outages, if your utility charges more in the evening, or if it pays you less for extra solar power than it charges you for power. If you have full retail net metering, like most homes with Florida Power & Light, Duke Energy Florida or Tampa Electric, a battery rarely saves enough to pay for itself. One home battery costs about $12,000 to $17,000 installed.
Key takeaways
- A battery stores extra daytime solar power for the evening and keeps your lights on when the grid goes down.
- Without a battery, solar panels shut off during an outage, even in full sun.
- Batteries pay off fastest on time-of-use rates or where extra solar power earns less than retail.
- With full retail net metering, the grid already works like a free battery.
- Most homes need 10 to 15 kWh to back up the essentials.
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What a solar battery actually does
Without a battery, the extra power your panels make during the day goes to the grid, and you pull power back at night. A battery keeps that extra power at home and uses it in the evening, when your home uses more and the panels have stopped.
During an outage, a battery with the right backup equipment separates your home from the grid and keeps the circuits you picked running. That is usually the fridge, lights, Wi-Fi, fans, a well pump and a few outlets, not the whole house.
When a battery is worth it
A battery is likely worth it if
- Your power goes out often or for days after storms
- Someone at home relies on medical equipment
- You have a well pump or need the fridge running
- Your utility charges more for power in the evening
- Your utility pays much less than retail for extra solar power
You can probably skip it if
- You have full retail net metering and few outages
- Your main goal is the fastest payback
- You already own a standby generator
- Your budget only covers the panels right now
Is a solar battery worth it in Florida?
For savings, usually not. Florida’s big power companies credit each extra kWh you send to the grid at the full retail rate, so storing it in a battery does not earn you more. See how net metering works in Florida.
For backup, often yes. Hurricanes and summer storms can knock out power for days, and a battery recharged by your panels each morning can keep the essentials running through a long outage. Some city-owned utilities and co-ops credit extra power at less than retail, which also makes a battery more valuable.
How much battery do you need?
Battery size is measured in kWh. Pick a size by listing what you want to keep running and for how long, not by matching the size of your panels.
| What you want to back up | Battery size | Typical setup |
|---|---|---|
| Fridge, lights, Wi-Fi and phones | 5 to 10 kWh | One small battery |
| Essentials plus fans, well pump and outlets | 10 to 15 kWh | One battery, like a Tesla Powerwall 3 |
| Most of the home with some central air | 20 to 30 kWh | Two batteries |
| Whole home through long outages | 30 kWh or more | Two or three batteries plus solar |
Central air uses the most power, often 25 to 40 kWh on a hot day. Your installer can size the battery to your actual loads.
How much does a solar battery cost?
| Setup | Typical cost installed |
|---|---|
| One 10 to 15 kWh battery | $12,000 to $17,000 |
| Two batteries for whole-home backup | $25,000 to $30,000 |
| Adding a battery to existing panels | Add $1,000 to $3,000 for extra parts |
The 30% federal tax credit for home batteries ended for homeowners who buy systems installed after December 31, 2025. Ask every installer to list the battery as its own line so you can see exactly what it adds. Our guide to solar battery cost in Florida has prices by brand and size.
See what a Tesla Powerwall costs to install
Battery vs a backup generator
| Solar battery | Standby generator | |
|---|---|---|
| Cost installed | $12,000 to $17,000 for one | $10,000 to $20,000 |
| Fuel | Recharges from your panels | Natural gas or propane |
| Noise | Silent | Loud while running |
| Long outages | As long as the sun recharges it | As long as you have fuel |
| Upkeep | Very little | Yearly service |
Compare more options in whole house solar generator cost.
Questions to ask before you add a battery
- Which circuits will it back up? Get the list in writing.
- Can it start my central air? Ask about a soft starter if you want AC during outages.
- What is the price with and without the battery? See exactly what it adds.
- What does the warranty cover? Most batteries carry a 10 year warranty.
- Where will it be mounted? In flood-prone areas, it should sit above flood level.
Compare free solar and battery quotes from vetted installers
Frequently asked questions
Is a solar battery worth the money?
It is worth it for backup power during outages and on time-of-use rates. With full retail net metering and few outages, a battery rarely pays for itself through bill savings alone.
How much does a solar battery cost?
About $12,000 to $17,000 installed for one 10 to 15 kWh battery, and about $25,000 to $30,000 for two batteries for whole-home backup.
Do solar panels work during a power outage without a battery?
No. Grid-tied solar panels shut off automatically when the grid goes down to protect utility crews. You need a battery and backup equipment to keep power on.
How long will a solar battery power my house?
One 13.5 kWh battery runs the fridge, lights, Wi-Fi and fans for about a day. With sun to recharge it, it can keep the essentials running through a long outage.
Can I add a battery to my existing solar panels?
Yes. Most systems can add a battery later, though you may need a new inverter or extra parts that add about $1,000 to $3,000.
Is there a tax credit for solar batteries in 2026?
Not for homeowners who buy. The 30% federal credit for home batteries ended for systems installed after December 31, 2025.
Where these numbers come from
Battery prices are typical installed ranges from recent installer pricing as of November 2026. Power use figures are typical estimates. Net metering rules follow Florida Public Service Commission Rule 25-6.065. We update this guide as prices change.