Solar Battery Cost per kWh of Storage: 2026 Prices and How to Compare Quotes

Solar battery cost per kWh for popular home batteries ran from about $967 to $1,429 per kWh installed in the first half of 2026, based on EnergySage marketplace quotes. A typical 13.5 kWh system came to about $15,650 before incentives, or roughly $1,160 per kWh. Cost per kWh is a quick way to compare quotes, but it leaves out power output, warranty and how much energy the battery will deliver over its life.

Key takeaways

• To get cost per kWh, divide the installed price by the battery's usable capacity in kWh.
• 2026 brand averages: Tesla about $967, FranklinWH about $1,232 and Enphase about $1,429 per kWh (EnergySage).
• Home batteries cost far more per kWh than utility-scale batteries, partly because of labor, permits and smaller system size.
• A lifetime view, such as price divided by warranted energy throughput, can be more useful than upfront cost per kWh.
• The federal residential clean energy credit does not apply to expenditures made after December 31, 2025.

How to calculate solar battery cost per kWh

The math is simple:

Cost per kWh = total installed price / usable battery capacity (kWh)

For example, a $15,647 quote for a 13.5 kWh battery works out to about $1,159 per kWh. Two tips make the number more useful:

• Use usable capacity. Datasheets may list total and usable capacity. Enphase lists the same total and usable figure for its IQ Batteries, but always check.
• Use the full installed price. Include labor, permits, extra panels or gateways and any electrical upgrades. That is what you will actually pay.

Also check cost per kW

Capacity (kWh) tells you how long a battery can run. Power (kW) tells you how much it can run at once, which matters for air conditioners, well pumps and other big loads. Dividing price by continuous kW gives a second useful number. Using EnergySage's 2026 brand averages and each maker's datasheet, our rough math gives:

• Tesla Powerwall 3: $13,055 / 11.5 kW = about $1,135 per kW
• FranklinWH aPower 2: $18,480 / 10 kW = about $1,848 per kW
• Enphase IQ Battery 10C: $14,290 / 7.08 kW = about $2,018 per kW

A battery that looks expensive per kWh may be good value if you need high power, and the reverse can also be true.

Solar battery cost per kWh by brand in 2026

EnergySage published average prices for the 10 most-quoted batteries on its marketplace in the first half of 2026. Here are several of them.

Source: EnergySage, updated July 2026. Its list ran from about $342 per kWh at the low end to about $3,505 per kWh at the high end, so outliers exist in both directions. In a separate review updated May 2026, EnergySage put the FranklinWH aPower 2 at about $1,177 per kWh. For total project prices, see how much a home battery costs.

Why home batteries cost more per kWh than grid batteries

You may see headlines about battery prices of a few hundred dollars per kWh. Those usually refer to utility-scale projects. A June 2025 report from NREL (now the National Laboratory of the Rockies) put 2024 costs for 4-hour utility-scale battery systems at about $334 per kWh.

Home systems cost more per kWh for practical reasons:

• Each install has its own design, permit, inspection and utility paperwork.
• Labor is a large share. EnergySage says equipment is about 50% to 60% of a home battery's price, with labor and planning making up most of the rest.
• Home batteries include an inverter, controls and backup hardware in a small package.

The lab's Annual Technology Baseline models a typical home battery as a 5 kW, 12.5 kWh lithium iron phosphate (LFP) system with a 15-year life and 85% round-trip efficiency. It expects most future cost declines to come from the battery pack, with smaller cuts in installation and other costs.

What cost per kWh does not tell you

Two batteries with the same price per kWh can be very different products. Check these specs too:

• Power (kW): How much the battery can run at once. The Powerwall 3 lists 11.5 kW continuous, while the original FranklinWH aPower listed 5 kW.
• Round-trip efficiency: How much energy you get back. Enphase lists 90% (AC) for its IQ Batteries and FranklinWH lists 90% for the aPower 2, each measured under its own test conditions.
• Warranty: Years, cycles or throughput, and the capacity you are guaranteed at the end.
• Coupling: Whether you also need a new inverter. See AC-coupled vs DC-coupled batteries.

Lifetime cost per kWh delivered

A more complete measure divides the price by the energy the battery is warranted to deliver. The figures below are our own rough calculations, using EnergySage's 2026 brand averages and each maker's warranty terms. They ignore efficiency losses and financing, and real use may be lower than the warranty limit.

Tesla's warranty is limited by time (10 years) rather than throughput for normal home uses, so a per-kWh figure from its 37.8 MWh cap would understate what most owners can use. Compare these per-kWh figures with what you pay for peak-hour grid power to judge whether bill savings alone could cover the battery. Our time-of-use rates guide explains how peak pricing works.

Worked example: comparing two battery quotes

Here is how to use cost per kWh with two made-up quotes. The numbers are for illustration only.

• Quote A: $14,000 for a 10 kWh battery. That is $1,400 per kWh.
• Quote B: $16,500 for a 15 kWh battery. That is $1,100 per kWh.

Quote B costs more in total but less per kWh. Whether that is the better deal depends on your needs. If you only need enough storage to cover a few evening hours, the extra 5 kWh may sit unused. If you want longer backup, the larger battery could be the better value.

Then look past capacity. Check each battery's continuous power, its warranty years and end-of-warranty capacity, and whether either quote includes a new inverter, subpanel or main panel upgrade. A lower cost per kWh can hide extra charges elsewhere in the contract.

How capacity fade affects the math

Batteries slowly lose capacity. Warranties set the minimum. Tesla guarantees 70% of the Powerwall's 13.5 kWh rating at 10 years. Enphase guarantees at least 60% of nameplate capacity on its IQ Batteries through the warranty term. A battery that holds more of its capacity for longer delivers more energy for the same price, which lowers your real cost per kWh over time.

How incentives change the cost per kWh

The IRS says the residential clean energy credit, which covered batteries of at least 3 kWh, is not available for expenditures made after December 31, 2025. Older cost-per-kWh figures that include a 30% discount are out of date for new installs. For a battery, the expenditure counts as made when installation is complete, so a battery finished in 2026 does not qualify.

State and utility programs can still lower the price. EnergySage cites California's SGIP, which can exceed $1,000 per kWh for some customers, and Connecticut's Energy Storage Solutions program offering up to $16,000. Check current rules and remaining budgets before counting on any program. Then weigh the result against the value of backup and bill savings in are solar batteries worth it.

Next steps

Ask every installer for the usable kWh, continuous kW, warranty terms and an itemized price. Calculate cost per kWh for each, then run the full quotes through our solar quote checker.