Solar panels in Billings, MT
Roofs in Billings get about 1,459 hours of usable sunlight a year — less than 57% of the cities we've measured. Here's what that means in cost, savings and payback, using real rooftop data rather than a national average.
Check your specific roof in Billings → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Billings solar system costs
A 22-panel system (8.8 kW) is about right for an average Billings home using 10,800 kWh a year. It would produce roughly 10,913 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,968 | $6,384 | $480 | 13.3 yrs |
| 12 panels | 4.8 kW | 5,953 | $9,576 | $720 | 13.3 yrs |
| 16 panels | 6.4 kW | 7,937 | $12,768 | $960 | 13.3 yrs |
| 20 panels | 8 kW | 9,921 | $15,960 | $1,200 | 13.3 yrs |
| 26 panels | 10.4 kW | 12,898 | $20,748 | $1,370 | 15.1 yrs |
How we worked this out for Billings
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Billings rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,459 sun hrs × 0.85 system losses |
496 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 496 kWh per panel |
22 panels |
| 3 | System size 22 panels × 400W |
8.80 kW |
| 4 | Annual production 8.80 kW × 1,459 hrs × 0.85 |
10,913 kWh/yr |
| 5 | Installed cost 8,800 W × $2.85 per watt, then −30% federal credit |
$17,556 |
| 6 | Annual saving 3,780 kWh used as generated × 12.1¢ + 7,133 kWh exported × 12.1¢ |
$1,310/yr |
| 7 | Payback $17,556 ÷ $1,310 per year |
13.4 years |
Step 6 matters more than it looks. Only 35% of what a system this size produces in Billings is used the moment it is generated; the other 7,133 kWh is exported and credited one-for-one under net metering. Because exports here are credited at or near retail, that split changes the payback very little — 13.3 years against the 13.4 we show. In places where exports pay a fraction of retail the same split moves payback by years, which is why we model it explicitly rather than assuming.
Assumptions: 400W panels, 15% system losses (inverter, wiring, heat, soiling), $2.85/W installed, 10,800 kWh typical annual household use, 12.1¢/kWh electricity. Change any of those and every figure above moves — which is exactly why a single national "solar costs X" number is misleading.
Notice that payback barely improves as systems get bigger, and eventually gets worse. That's because you can only save money on electricity you were going to buy anyway. Once a system covers your usage, extra panels mostly generate exports at a much lower rate.
Why Billings gets 1,459 sun hours
That figure comes from Google's analysis of real rooftops across Billings — it already accounts for shading from trees, chimneys and neighbouring buildings, which is why it's lower than the raw "hours of daylight" figures you'll see elsewhere. An unusually open, unshaded roof in Billings reaches about 1,652 hours, roughly 13% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,459 hrs/yr |
|---|---|
| Unshaded roof | 1,652 hrs/yr |
| Electricity rate (Montana avg) | 12.1¢/kWh |
| Installed cost assumed | $2.85/W |
| Panel size assumed | 400 W |
| Federal tax credit | 30% |
| Typical household usage | 10,800 kWh/yr |
| Power used as generated | 35% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 7 |
| Google imagery from | 2022 |
When Billings actually produces
Annual totals hide the thing that catches people out: 39% of Billings's yearly sunlight arrives in May–July, and just 11% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 54 | |
| Feb | 80 | |
| Mar | 115 | |
| Apr | 153 | |
| May | 182 | |
| Jun | 195 | |
| Jul | 188 | |
| Aug | 164 | |
| Sep | 129 | |
| Oct | 90 | |
| Nov | 60 | |
| Dec | 48 |
That is a severe seasonal swing — Billings produces roughly 4.1× as much in Jun as in Dec. A system sized to cover your annual usage will overproduce badly in summer and fall well short in winter, so how your utility credits exported power matters more here than in most places.
The annual total is measured from Google's rooftop imagery. Its split across months is calculated from solar geometry at Billings's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Billings compares to the other 788 cities
| Measure | Billings | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,459 hrs | 447th |
| Sunlight lost to shade | 12% | 37th most |
| Median roof size | 357 m² | 50th largest |
| Electricity rate | 12.1¢ | 692nd highest |
| Payback | 13.4 yrs | 662nd fastest |
| Grid carbon | 696 kg/MWh | 218th dirtiest |
What actually stands out about Billings:
- Shading is a real problem here. Billings loses 12% of its potential sunlight to trees, chimneys and neighbouring buildings — the 37th-worst of the 788 cities measured. Panel placement matters more here than in most places, and a roof survey is worth more than a phone quote.
- Plenty of roof to work with. Typical roofs here fit around 123 panels — roughly 5× what an average home needs. Roof size will not be what limits your system in Billings.
- Large roofs. At a median of 357 m², Billings has the 50th-largest typical roof footprint we've measured.
Cities with almost the same sunlight
These are the closest matches to Billings's 1,459 usable sun hours from other states and provinces. Same sunlight, different electricity prices — which is usually what decides whether solar is worth it.
| City | Sun hrs | Rate | Payback |
|---|---|---|---|
| Detroit, MI | 1,459 | 19.1¢ | 8.5 yrs |
| Schaumburg, IL | 1,459 | 16.3¢ | 9.9 yrs |
| Terre Haute, IN | 1,459 | 15.3¢ | 10.6 yrs |
| Walla Walla, WA | 1,459 | 11.3¢ | 14.3 yrs |
Nearby cities
See all of Montana → statewide sunlight, rates, incentives and every city we've measured.
Billings solar questions
How many solar panels do I need in Billings?
About 22 panels for an average home using 10,800 kWh a year. Billings roofs get 1,459 usable sun hours, so each 400W panel produces roughly 496 kWh annually. A typical Billings roof fits about 123 panels, so roof space is unlikely to be your limit.
Is solar worth it in Billings?
At 12.1¢/kWh and 1,459 sun hours, a typical system pays for itself in about 13.4 years and returns roughly $15,200 over a 25-year panel life. That is slower than average, so compare several quotes before committing. Exported power earns full retail credit here.
How much do solar panels cost in Billings?
A 8.8 kW system costs about $25,080 before incentives and $17,556 after the 30% federal tax credit. That works out near $2.85 per watt installed. Roof pitch, shading, electrical panel upgrades and equipment choice move the price most, which is why quotes for the same house can differ by thousands.
Worth reading before you buy
Estimates only, generated 2026-08-22 from Google Solar API rooftop samples and average Montana electricity rates. Not a quote and not financial advice. Your roof, usage, utility plan and local incentives will change these numbers — get real quotes before buying.