Home Battery Storage ROI Calculator
Example: Installed battery cost: 13000 $ · Federal storage tax credit: 30 % · Energy shifted per day: 10 kWh · Peak electricity rate: 0.42 $/kWh · Off-peak rate: 0.14 $/kWh
| Payback period | 8.9 |
| Net cost after credit | $9,100 |
| Annual arbitrage savings | $1,022 |
Worked example
A $13,000 installed battery qualifies for the 30% federal credit, cutting the net cost to $9,100. Shifting 10 kWh a day from a $0.42 peak rate to a $0.14 off-peak rate captures a $0.28 spread, or $2.80 a day and about $1,022 a year. Dividing $9,100 by $1,022 gives a payback of roughly 8.9 years from arbitrage alone, before you count the value of backup power during outages.
Frequently asked questions
Is a home battery worth it just for savings?
On pure rate arbitrage, batteries often take the better part of a decade to pay back, so the case is strongest where the peak-to-off-peak spread is large, outages are frequent and costly, or you want to store your own solar rather than export it cheaply. Backup resilience is a real benefit this calculator does not price in.
Does the tax credit apply to batteries alone?
Since 2023 standalone home batteries of at least 3 kWh qualify for the 30% Residential Clean Energy Credit even without solar. Before that, storage generally had to be charged by solar to qualify. Enter 30 for projects placed in service under the current rules.
How much energy can I realistically shift?
You can only shift as much as your usable battery capacity and your peak-hour usage allow. A typical 13.5 kWh battery might reliably cycle 10 to 12 kWh a day. Do not enter more than your battery can deliver during the peak window, or the savings will be overstated.
What if I do not have time-of-use rates?
Without a peak and off-peak price spread, arbitrage savings are close to zero and the battery's value comes almost entirely from backup power and solar self-consumption. Many utilities let you opt into a time-of-use plan, which is often what makes a battery pencil out.