2026 · No Federal Tax Credit · NREL + EIA Data
Solar Panels in Montana: Cost, Payback & ROI (2026)
Is solar still worth it in Montana after the 30% federal tax credit expired? These pre-computed estimates use NREL PVWatts production data and current 11.8¢/kWh Montana electricity rates for a typical home using 900 kWh/month.
Section 25D (30% federal solar tax credit) expired December 31, 2025
All numbers below reflect 2026 math with no federal residential credit. State incentives, where applicable, are noted in the section below.
Montana Solar at a Glance
Based on a 900 kWh/month home ($106/mo electric bill at 11.8¢/kWh), 100% offset, no state rebate applied.
7.8 kW
For 900 kWh/month home
$23,087
At $2.95/W (LBNL 2024 avg)
15.6 years
Without state rebate
$1,274
Estimated annual savings
$40,754
Cumulative before rebate
$17,667
Savings minus system cost
11.8¢/kWh
below average vs. 16.0¢ U.S. avg · EIA 2025
1,380 kWh/kW/yr
moderate · 4.2 peak sun hrs/day · NREL PVWatts
Is Solar Worth It in Montana in 2026?
Montana's 11.8¢/kWh rate and 1,380 kWh/kW/year solar resource make it a moderately viable solar state, especially in the eastern and southern parts of the state where sun hours are higher. NorthWestern Energy is the primary utility.
For a typical Montana home consuming 900 kWh per month, our calculation shows a 7.8 kW system needed for 100% offset. At the current national average installed cost of $2.95/W (LBNL Tracking the Sun 2024), that's $23,087 gross before any state rebates. Year-one savings of $1,274 grow each year as electricity rates escalate — the model assumes 2.5%/year (EIA AEO 2024).
The 15.6 years payback period is longer than the national average due to low electricity rates or limited solar resource. Over 25 years — the standard warranty period for most premium panels — a Montana homeowner following this profile would save an estimated $40,754 total, for a net benefit of $17,667 after recovering the system cost.
Year-by-Year Savings Snapshot: First 10 Years
Based on 7.8 kW system, 0.5%/yr degradation, 2.5%/yr rate escalation, no state rebate.
| Year | Production (kWh) | Annual Savings | Cumulative |
|---|---|---|---|
| Year 1 | 10,800 | $1,274 | $1,274 |
| Year 2 | 10,746 | $1,300 | $2,574 |
| Year 3 | 10,692 | $1,326 | $3,900 |
| Year 4 | 10,639 | $1,352 | $5,252 |
| Year 5 | 10,586 | $1,379 | $6,630 |
| Year 6 | 10,533 | $1,406 | $8,037 |
| Year 7 | 10,480 | $1,434 | $9,471 |
| Year 8 | 10,428 | $1,463 | $10,933 |
| Year 9 | 10,375 | $1,492 | $12,425 |
| Year 10 | 10,324 | $1,521 | $13,946 |
System cost to recover: $23,087. Table shows savings without state rebate applied. Use the interactive calculator to enter your actual bill and any rebate.
Solar Incentives in Montana (2026)
Montana offers a small state income tax credit for solar and exempts solar from property tax on the added home value.
- Montana alternative energy investment tax credit (small)
- Property tax exemption on solar added value
- Net metering via NorthWestern Energy
Incentive programs change frequently. Verify current offerings at dsireusa.org or directly with your utility before making any purchasing decision.
How We Calculate Montana Solar ROI
These estimates use the same methodology as our interactive solar ROI calculator, applied to Montana-specific data:
System cost
$2.95/W installed
LBNL Tracking the Sun 2024
Solar production
1,380 kWh/kW/yr
NREL PVWatts v8
Electricity rate
11.8¢/kWh
EIA Residential Rates 2025
Rate escalation
2.5%/year
EIA Annual Energy Outlook 2024
Panel degradation
0.5%/year
NREL (Jordan & Kurtz, median)
System lifetime
25 years
Standard warranty period
No Section 25D (federal residential solar credit) is included — it expired December 31, 2025. State incentives are not reflected in these pre-computed figures; use the interactive calculator to enter specific rebate amounts.
Calculate With Your Actual Numbers
The figures above use statewide averages. Enter your actual monthly bill, any Montana rebate amounts, and your offset target in our interactive calculator for a personalized estimate.
Frequently Asked Questions — Solar in Montana
Compare Other States
Estimates are based on NREL PVWatts v8 production data, EIA 2025 electricity rates, and LBNL 2024 installed cost benchmarks. Actual savings vary by roof pitch, shading, utility rate structure, and local permit costs. This is not financial advice. Consult a licensed solar installer before making any purchasing decision.