Are Solar Batteries Worth It? When Home Storage Pays Off

What a battery does for a solar home

A battery stores midday solar output that would otherwise go to the grid and releases it in the evening, when the panels have stopped producing and electricity is often most expensive. It can also keep essential circuits running during a power outage — something a standard grid-tied solar system cannot do on its own, because it shuts off when the grid goes down.

Batteries were paired with 37% of new US residential solar systems in 2025, up from 25% a year earlier, according to Berkeley Lab. Most of that growth came from states where exports earn little.

What batteries cost

Installed prices for home batteries generally run about $1,000 to $1,300 per kWh of storage capacity. A popular 13.5 kWh unit typically costs around $12,000 to $16,000 installed, more if your electrical panel needs an upgrade. Berkeley Lab's 2025 data shows cash-purchase solar systems with storage cost a median $2.10 per watt more than solar alone.

The 30% federal tax credit that used to cover home batteries ended with the solar credit for systems installed after 2025. Some states and utilities pay for batteries in other ways — upfront rebates, or payments for letting the utility draw on your battery during peak demand — so check what's offered locally.

The math: a battery is worth the gap between retail and export

A battery earns money only by moving power from one value to another. Each kWh it shifts from export to evening self-use is worth the difference between what you pay for electricity and what exports earn, minus about 10% lost charging and discharging.

• Under net metering, that gap is zero. Exports already earn the retail price, so a battery saves little or nothing on your bill. It's backup power, priced like backup power.
• Under net billing, the gap can be large. Say retail power costs 30¢ and exports earn 7¢. Shifting 10 kWh a day saves about 30¢ − 7¢ = 23¢ per kWh, times 10 kWh, times 365 days, times 90% efficiency — roughly $750 a year. Against a $13,000 battery, that's a payback of more than 15 years with no incentives, close to a battery's useful life.
• Time-of-use rates widen the gap. If evening power costs much more than midday power, a battery also saves by avoiding the most expensive hours.

Berkeley Lab's research reached the same conclusion: in most places, bill savings alone have not justified the upfront cost of a battery. Where batteries make financial sense, it's usually a combination of low export rates, high evening prices and a local incentive.

Where batteries make the most sense

• Hawaii and California. Hawaii's current program pays nothing for exports between 9 a.m. and 4 p.m., and California's export credits average 7.0¢ against retail power around 33.3¢. Most new solar systems in both states now include storage.
• Places with frequent or long outages. If losing power costs you food, medical equipment, a sump pump or work, backup has real value even where it doesn't lower the bill.
• Utility programs that pay for battery access. Where a utility pays you to discharge during peak events, that income can cover a meaningful share of the cost.

Cheaper ways to get backup

If you mainly want to keep the fridge, lights, internet and phones running through an occasional outage, a portable power station costs a fraction of a whole-home battery and needs no installation; paired with a few portable solar panels, it can recharge during a longer outage. A standby generator is the traditional option for whole-house backup.

Leasing or financing a battery

Companies that own batteries on customers' homes can still claim a business tax credit for storage, and unlike solar panels, storage isn't subject to the end-of-2027 deadline. That can make leased or third-party-owned batteries cheaper than buying one outright. Compare total payments over the term against the savings you'd realistically get — our lease vs buy guide walks through it.

To see how exports are credited where you live, check your state page.