Solar panels in Nampa, ID
Roofs in Nampa get about 1,677 hours of usable sunlight a year — more than 70% 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 Nampa → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Nampa solar system costs
A 19-panel system (7.6 kW) is about right for an average Nampa home using 10,800 kWh a year. It would produce roughly 10,833 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 4,561 | $6,384 | $511 | 12.5 yrs |
| 12 panels | 4.8 kW | 6,842 | $9,576 | $766 | 12.5 yrs |
| 16 panels | 6.4 kW | 9,123 | $12,768 | $1,022 | 12.5 yrs |
| 20 panels | 8 kW | 11,404 | $15,960 | $1,227 | 13 yrs |
| 26 panels | 10.4 kW | 14,825 | $20,748 | $1,322 | 15.7 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 Nampa gets 1,677 sun hours
That figure comes from Google's analysis of real rooftops across Nampa — 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 Nampa reaches about 1,715 hours, roughly 2% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,677 hrs/yr |
|---|---|
| Unshaded roof | 1,715 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 | 13 |
| Google imagery from | 2022 |
Nearby cities
See all of Idaho → statewide sunlight, rates, incentives and every city we've measured.
Nampa solar questions
How many solar panels do I need in Nampa?
About 19 panels for an average home. Nampa roofs get 1,677 usable sun hours a year, so each 400W panel produces roughly 570 kWh annually.
Is solar worth it in Nampa?
At 11.2¢/kWh and 1,677 sun hours, a typical system pays for itself in about 12.5 years and returns roughly $15,101 over 25 years. That is slower than the national average, so compare quotes carefully.
How much do solar panels cost in Nampa?
A 7.6 kW system costs about $21,660 before incentives and $15,162 after the 30% federal tax credit. Prices vary by installer, roof complexity and equipment.
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.