Solar panels in Twin Falls, ID
Roofs in Twin Falls get about 1,773 hours of usable sunlight a year — more than 76% 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 Twin Falls → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Twin Falls solar system costs
A 18-panel system (7.2 kW) is about right for an average Twin Falls home using 10,800 kWh a year. It would produce roughly 10,851 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 4,823 | $6,384 | $540 | 11.8 yrs |
| 12 panels | 4.8 kW | 7,234 | $9,576 | $810 | 11.8 yrs |
| 16 panels | 6.4 kW | 9,645 | $12,768 | $1,080 | 11.8 yrs |
| 20 panels | 8 kW | 12,056 | $15,960 | $1,245 | 12.8 yrs |
| 26 panels | 10.4 kW | 15,673 | $20,748 | $1,346 | 15.4 yrs |
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 Twin Falls gets 1,773 sun hours
That figure comes from Google's analysis of real rooftops across Twin 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 Twin Falls reaches about 1,820 hours, roughly 3% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,773 hrs/yr |
|---|---|
| Unshaded roof | 1,820 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 | 35% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 7 |
| Google imagery from | 2020 |
When Twin Falls actually produces
Annual totals hide the thing that catches people out: 37% of Twin Falls's yearly sunlight arrives in May–July, and just 12% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 74 | |
| Feb | 103 | |
| Mar | 142 | |
| Apr | 183 | |
| May | 213 | |
| Jun | 226 | |
| Jul | 219 | |
| Aug | 195 | |
| Sep | 157 | |
| Oct | 114 | |
| Nov | 81 | |
| Dec | 66 |
Twin Falls produces about 3.4× 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 Twin Falls's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Twin Falls compares to the other 673 cities
| Measure | Twin Falls | Rank of 673 |
|---|---|---|
| Usable sunlight | 1,773 hrs | 160th |
| Sunlight lost to shade | 3% | 580th most |
| Median roof size | 156 m² | 497th largest |
| Electricity rate | 11.2¢ | 650th highest |
| Payback | 11.9 yrs | 490th fastest |
| Grid carbon | 696 kg/MWh | 262nd dirtiest |
What actually stands out about Twin Falls:
- Sunnier than the rest of Idaho. Twin Falls roofs get 8% more usable sunlight than the typical Idaho city we've measured — statewide averages will understate what you can expect here.
- 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.
- Older imagery. Google's aerial capture of Twin Falls dates from 2020. Tree growth and new construction since then are not reflected.
Cities with almost the same sunlight
These are the closest matches to Twin Falls's 1,773 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 |
|---|---|---|---|
| Port St. Lucie, FL | 1,773 | 15.3¢ | 8.7 yrs |
| Boca Raton, FL | 1,773 | 15.3¢ | 8.7 yrs |
| West Palm Beach, FL | 1,775 | 15.3¢ | 8.7 yrs |
| Brownsville, TX | 1,770 | 15.1¢ | 8.8 yrs |
Nearby cities
See all of Idaho → statewide sunlight, rates, incentives and every city we've measured.
Twin Falls solar questions
How many solar panels do I need in Twin Falls?
About 18 panels for an average home using 10,800 kWh a year. Twin Falls roofs get 1,773 usable sun hours, so each 400W panel produces roughly 603 kWh annually. A typical Twin Falls roof fits about 54 panels, so roof space is unlikely to be your limit.
Is solar worth it in Twin Falls?
At 11.2¢/kWh and 1,773 sun hours, a typical system pays for itself in about 11.9 years and returns roughly $15,912 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 Twin Falls?
A 7.2 kW system costs about $20,520 before incentives and $14,364 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.