Solar panels in Thornton, CO
Roofs in Thornton get about 1,756 hours of usable sunlight a year — more than 74% 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 Thornton → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Thornton solar system costs
A 19-panel system (7.6 kW) is about right for an average Thornton home using 10,800 kWh a year. It would produce roughly 11,344 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 4,776 | $6,384 | $707 | 9 yrs |
| 12 panels | 4.8 kW | 7,164 | $9,576 | $1,060 | 9 yrs |
| 16 panels | 6.4 kW | 9,553 | $12,768 | $1,414 | 9 yrs |
| 20 panels | 8 kW | 11,941 | $15,960 | $1,641 | 9.7 yrs |
| 26 panels | 10.4 kW | 15,523 | $20,748 | $1,773 | 11.7 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 Thornton gets 1,756 sun hours
That figure comes from Google's analysis of real rooftops across Thornton — 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 Thornton reaches about 1,865 hours, roughly 6% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,756 hrs/yr |
|---|---|
| Unshaded roof | 1,865 hrs/yr |
| Electricity rate (Colorado avg) | 14.8¢/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 | 33% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 16 |
| Google imagery from | 2024 |
Nearby cities
See all of Colorado → statewide sunlight, rates, incentives and every city we've measured.
Thornton solar questions
How many solar panels do I need in Thornton?
About 19 panels for an average home. Thornton roofs get 1,756 usable sun hours a year, so each 400W panel produces roughly 597 kWh annually.
Is solar worth it in Thornton?
At 14.8¢/kWh and 1,756 sun hours, a typical system pays for itself in about 9.4 years and returns roughly $25,301 over 25 years. That is a solid return.
How much do solar panels cost in Thornton?
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 Colorado 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.