What a battery costs before any subsidy
A home battery stores electricity a solar panel makes during the day so a house can use it after dark instead of buying grid power. The common size installers quote is 13.5 kilowatt hours, the unit that measures how much electricity a battery holds. That size costs a national average of 15,647 dollars before any subsidy, EnergySage reports from its own installer quotes. The same size battery in California averages slightly less, 14,567 dollars.
Figures are state averages built from installer quotes in the same EnergySage data set that gives the national and California total prices above.
Show the numbers
| California average | 1,079 |
| Lowest state average | 761 |
| Highest state average | 3,505 |
Prices for that battery range from 761 dollars per kilowatt hour in the cheapest state to 3,505 dollars in the most expensive, so location changes the bill by thousands of dollars.
The rate that decides the payback
A payback period is the number of years bill savings take to equal what a system cost. Since 15 December 2022, new solar customers of the big California utilities must join the Net Billing Tariff, a rate the California Public Utilities Commission adopted that charges far more for power at a few peak hours than the rest of the day. Solar alone under this tariff saves a customer 100 dollars a month, the commission states. Solar with a battery saves at least 136 dollars a month, because it covers those peak hours with stored power instead of grid power. The commission says that trade should pay off in 9 years or less on average.
We are launching the solar and storage industry into the future so that it can support the modern grid.
Alice Reynolds, president of the California Public Utilities Commission. Source 1.
The rule this replaced
Before this tariff, solar customers followed net metering rules with no big gap between peak and off peak prices. A typical solar customer with no battery paid back a system in 3 to 5.5 years depending on the utility, the commission states. That is not the same customer with and without a battery on the same rate. It is 2 different rate designs, one before the state pushed customers toward a battery and one after. Fewer than 10% of solar customers under the old rules had added one. That gap is why the commission built the new rate around a bigger price difference.
Other ways to shorten it
California also runs the Self Generation Incentive Program, a rebate that EnergySage says can add more than 1,000 dollars per kilowatt hour toward the cost. On a 13.5 kilowatt hour battery, that is more than 13,500 dollars, a figure this article calculated by multiplying the 2 numbers, not one EnergySage states directly.
The incentive cap value bar is calculated for this article, multiplying the Self Generation Incentive Program cap of 1,000 dollars per kilowatt hour by the 13.5 kilowatt hour battery size used in the other 2 bars. EnergySage states the per kilowatt hour figure only, not the total.
Show the numbers
| National average | 15,647 |
| California average | 14,567 |
| Incentive cap value | 13,500 |
In Massachusetts, a battery owner can join ConnectedSolutions, a program paying up to 275 dollars per kilowatt for each event the utility calls, mostly summer and winter peak days. EnergySage states a customer can earn upwards of 1,500 dollars with a typical battery, enough alone to pay back a system in under 10 years, separate from bill savings.
The company betting people skip the question
Base Power, a Texas company, offers a different answer. Do not buy the battery. It installs one for an upfront fee of 95 to 695 dollars depending on location, instead of the more than 10,000 dollars the company says a comparable battery costs outright, then charges an electricity subscription. The company had installed batteries at 17,000 homes as of August 2026, mostly in Texas, and is expanding into Illinois.
There's a real need on the grid for capacity in Illinois and Texas and frankly everywhere else in the U.S. now.
Justin Lopas, co founder and chief operating officer of Base Power. Source 5.
No source among the 5 states a faster payback than 9 years for a battery bought outright with no incentive and no time of use rate. A home battery can pay for itself, but only under a rate built to make that happen, and even then not quickly.