Solar panels in Idaho Falls, ID
Roofs in Idaho Falls get about 1,646 hours of usable sunlight a year — more than 68% 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 Idaho Falls → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Idaho Falls solar system costs
A 20-panel system (8 kW) is about right for an average Idaho Falls home using 10,800 kWh a year. It would produce roughly 11,193 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 4,477 | $6,384 | $501 | 12.7 yrs |
| 12 panels | 4.8 kW | 6,716 | $9,576 | $752 | 12.7 yrs |
| 16 panels | 6.4 kW | 8,954 | $12,768 | $1,003 | 12.7 yrs |
| 20 panels | 8 kW | 11,193 | $15,960 | $1,221 | 13.1 yrs |
| 26 panels | 10.4 kW | 14,551 | $20,748 | $1,315 | 15.8 yrs |
How we worked this out for Idaho Falls
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Idaho Falls rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,646 sun hrs × 0.85 system losses |
560 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 560 kWh per panel |
20 panels |
| 3 | System size 20 panels × 400W |
8.00 kW |
| 4 | Annual production 8.00 kW × 1,646 hrs × 0.85 |
11,193 kWh/yr |
| 5 | Installed cost 8,000 W × $2.85 per watt, then −30% federal credit |
$15,960 |
| 6 | Annual saving 3,780 kWh used as generated × 11.2¢ + 7,413 kWh exported × 11.2¢ |
$1,221/yr |
| 7 | Payback $15,960 ÷ $1,221 per year |
13.1 years |
Step 6 matters more than it looks. Only 34% of what a system this size produces in Idaho Falls is used the moment it is generated; the other 7,413 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 — 12.7 years against the 13.1 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, 11.2¢/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 Idaho Falls gets 1,646 sun hours
That figure comes from Google's analysis of real rooftops across Idaho Falls — 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 Idaho Falls reaches about 1,753 hours, roughly 7% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,646 hrs/yr |
|---|---|
| Unshaded roof | 1,753 hrs/yr |
| Electricity rate (Idaho avg) | 11.2¢/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 | 34% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 13 |
| Google imagery from | 2024 |
When Idaho Falls actually produces
Annual totals hide the thing that catches people out: 38% of Idaho Falls's yearly sunlight arrives in May–July, and just 12% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 66 | |
| Feb | 94 | |
| Mar | 131 | |
| Apr | 171 | |
| May | 200 | |
| Jun | 212 | |
| Jul | 206 | |
| Aug | 182 | |
| Sep | 145 | |
| Oct | 105 | |
| Nov | 73 | |
| Dec | 59 |
Idaho Falls produces about 3.6× as much in Jun as in Dec — a normal mid-latitude swing. Expect real winter shortfall and summer surplus rather than steady year-round output.
The annual total is measured from Google's rooftop imagery. Its split across months is calculated from solar geometry at Idaho Falls's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Idaho Falls compares to the other 788 cities
| Measure | Idaho Falls | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,646 hrs | 250th |
| Sunlight lost to shade | 6% | 292nd most |
| Median roof size | 390 m² | 31st largest |
| Electricity rate | 11.2¢ | 745th highest |
| Payback | 13.1 yrs | 646th fastest |
| Grid carbon | 696 kg/MWh | 216th dirtiest |
What actually stands out about Idaho Falls:
- Plenty of roof to work with. Typical roofs here fit around 115 panels — roughly 5× what an average home needs. Roof size will not be what limits your system in Idaho Falls.
- Large roofs. At a median of 390 m², Idaho Falls has the 31st-largest typical roof footprint we've measured.
- Cheap electricity is the headwind. Idaho power costs about 11.2¢/kWh. Low rates are good news generally, but they lengthen solar payback — there is simply less bill to displace.
Cities with almost the same sunlight
These are the closest matches to Idaho Falls's 1,646 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 |
|---|---|---|---|
| Savannah, GA | 1,646 | 14.1¢ | 10.4 yrs |
| North Charleston, SC | 1,646 | 14.2¢ | 10.3 yrs |
| League City, TX | 1,645 | 15.1¢ | 9.7 yrs |
| Salina, KS | 1,642 | 14.1¢ | 10.4 yrs |
Nearby cities
See all of Idaho → statewide sunlight, rates, incentives and every city we've measured.
Idaho Falls solar questions
How many solar panels do I need in Idaho Falls?
About 20 panels for an average home using 10,800 kWh a year. Idaho Falls roofs get 1,646 usable sun hours, so each 400W panel produces roughly 560 kWh annually. A typical Idaho Falls roof fits about 115 panels, so roof space is unlikely to be your limit.
Is solar worth it in Idaho Falls?
At 11.2¢/kWh and 1,646 sun hours, a typical system pays for itself in about 13.1 years and returns roughly $14,555 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 Idaho Falls?
A 8 kW system costs about $22,800 before incentives and $15,960 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 Idaho 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.