Is a Home Battery Worth It in Montana? 2026 Payback
A 13.5 kWh battery costs around $14,850 installed in Montana and saves about $0 a year on the bill — so it earns nothing at all on the bill. What it genuinely buys you is 5.5 hours a year of kept power.
- Bill payback
- Never
- warranty 10 yr
- Bill saving
- $0/yr
- no value stream
- Net cost
- $14,850
- 13.5 kWh installed
- Outages
- 5.5 hr/yr
- backup value, not payback
Unranked — does not pay back within the modelled period. The national median is 60+ yr and the best case is Hawaii at 10 yr 9 mo.
Home battery calculator — Montana
Bill savings and backup value, kept separate on purpose.
Pays for itself on bills in
Never
Nothing to earn here — no time-of-use spread and exports already credited at full retail.
Bill saving / year
$0
12.2 kWh usable
Net cost
$14,850
after incentives
Best strategy here
No viable value stream
These do not add up. A battery cycles about once a day, so it earns whichever is larger — not both.
Backup value — insurance, not return
Montana averages 5.5 hours of outage a year, so that is $138 of avoided disruption annually — by your own valuation. Deliberately excluded from the payback figure above.
The numbers behind it
| Battery modelled | 13.5 kWh (12.2 kWh usable) |
|---|---|
| Installed cost | $14,850 |
| Average electricity rate | 13.56¢ / kWh |
| Peak / off-peak spread | No TOU tariff |
| Solar export policy | Retail-rate net metering |
| Value of exported power | Full retail rate |
| Cycles assumed | 300 / year |
| Value from arbitrage | -$55 / yr |
| Value from storing solar | -$55 / yr |
| Bill saving (best of the two) | $0 / yr |
| Payback on bills | Never |
| Warranty | 10 years |
| Still unrecovered at 10 years | $14,850 |
| Average annual outage | 5.5 hours |
Why the two savings figures don’t add up
A battery holds one charge and gives it back once a day. It can either fill up cheaply overnight and discharge when power is expensive, or hold your midday solar until the evening — but the same stored kilowatt-hour cannot do both jobs. Quotes that list arbitrage savings and solar savings and then total them are counting one battery twice. In Montana the better of the two is worth $0 a year, and that is the figure used here.
Common questions
Is a home battery worth it in Montana?
Not financially. Montana credits solar exports at full retail and has no meaningful time-of-use spread, which leaves a battery nothing to arbitrage and nothing to rescue from cheap exports. It earns roughly $0 a year on your bill. Buy one for backup power if you want backup power — but not as an investment.
How much does a home battery cost in Montana?
Around $14,850 installed for 13.5 kWh, at roughly $1100 per kWh. Installation varies more than hardware does, and utility or state storage incentives can cut thousands off — those are the single biggest lever on whether the numbers work.
How much can a battery save on my Montana electricity bill?
Effectively nothing, on current tariffs. There is no peak/off-peak spread to exploit and exported solar already earns full retail, so shifting energy in time gains you no money.
Does backup power justify the cost?
That is a judgement, not a calculation. Montana averages 5.5 hours of interruption a year. At $25 an hour of kept power that is $138 a year of avoided disruption — but if you work from home, keep medical equipment running, or lose a freezer of food, your number is far higher. We keep it out of the payback figure because insurance is not a return.
Is it better to add more solar or a battery?
In Montana, exports earn full retail, so extra panels almost always beat a battery — the grid is already acting as a free battery for you.
How we calculate this
Round-trip efficiency is charged honestly: to deliver one usable kilowatt-hour you have to buy about 1.11, and ignoring that overstates arbitrage by roughly 11%. Usable capacity is 90% of nameplate.
Payback counts bill savings only. Backup power is valued separately at whatever you say an hour is worth, and never folded in — mixing insurance into a return is how batteries end up looking like investments.
Excluded by default: storage incentives (adjustable in the calculator), battery degradation, and any panel or wiring upgrades the install needs.
Data vintage: Electricity: EIA Electric Power Monthly Table 5.6.B (residential, May 2026 YTD). Solar resource: PVGIS v5.3 (EU JRC), ERA5 2005-2023. Gasoline: AAA state averages. Natural gas: EIA residential by state. Heating degree days: NOAA CPC population-weighted normals. Residential consumption: EIA Electric Sales, Revenue, and Average Price Table 5.A, average monthly kWh per residential customer, 2024. Vehicle miles: FHWA Highway Statistics 2023. Retrieved 2026-08-03/04 and 2026-08-21. Install costs, net-metering status, time-of-use spreads and outage hours remain estimates.
How Montana compares
| # | State | Bill payback period |
|---|---|---|
| 1 | Hawaii | 10 yr 9 mo |
| 2 | California | 15 yr 7 mo |
| 3 | Connecticut | 17 yr 8 mo |
| 4 | Alaska | 20 yr 4 mo |
| 5 | Michigan | 29 yr |
| 6 | Arizona | 37 yr 3 mo |
| 7 | Indiana | 39 yr 4 mo |
| 8 | Nevada | 40 yr 6 mo |
| 9 | Alabama | 40 yr 11 mo |
| 10 | Texas | 43 yr |
Computed from the same model as this page. Full national findings · how this is calculated · data sources