Solar panels in Keene, NH
Roofs in Keene get about 1,434 hours of usable sunlight a year — less than 73% 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 Keene → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Keene solar system costs
A 23-panel system (9.2 kW) is about right for an average Keene home using 10,800 kWh a year. It would produce roughly 11,214 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,900 | $6,384 | $987 | 6.5 yrs |
| 12 panels | 4.8 kW | 5,851 | $9,576 | $1,480 | 6.5 yrs |
| 16 panels | 6.4 kW | 7,801 | $12,768 | $1,974 | 6.5 yrs |
| 20 panels | 8 kW | 9,751 | $15,960 | $2,467 | 6.5 yrs |
| 26 panels | 10.4 kW | 12,677 | $20,748 | $2,851 | 7.3 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 Keene gets 1,434 sun hours
That figure comes from Google's analysis of real rooftops across Keene — 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 Keene reaches about 1,561 hours, roughly 9% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,434 hrs/yr |
|---|---|
| Unshaded roof | 1,561 hrs/yr |
| Electricity rate (New Hampshire avg) | 25.3¢/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 | 7 |
| Google imagery from | 2014 |
When Keene actually produces
Annual totals hide the thing that catches people out: 37% of Keene's yearly sunlight arrives in May–July, and just 12% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 59 | |
| Feb | 83 | |
| Mar | 115 | |
| Apr | 149 | |
| May | 173 | |
| Jun | 184 | |
| Jul | 178 | |
| Aug | 158 | |
| Sep | 127 | |
| Oct | 92 | |
| Nov | 64 | |
| Dec | 53 |
Keene produces about 3.5× 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 Keene's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Keene compares to the other 673 cities
| Measure | Keene | Rank of 673 |
|---|---|---|
| Usable sunlight | 1,434 hrs | 489th |
| Sunlight lost to shade | 8% | 132nd most |
| Median roof size | 112 m² | 622nd largest |
| Electricity rate | 25.3¢ | 99th highest |
| Payback | 6.7 yrs | 31st fastest |
| Grid carbon | 445 kg/MWh | 538th dirtiest |
What actually stands out about Keene:
- Small roofs. The median Keene roof is 112 m², smaller than 92% of cities measured — worth checking your own footprint before assuming a standard system fits.
- Sunnier than the rest of New Hampshire. Keene roofs get 6% more usable sunlight than the typical New Hampshire city we've measured — statewide averages will understate what you can expect here.
- Older imagery. Google's aerial capture of Keene dates from 2014. Tree growth and new construction since then are not reflected.
Cities with almost the same sunlight
These are the closest matches to Keene's 1,434 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 |
|---|---|---|---|
| St. Catharines, ON | 1,434 | 15.2¢ | 15.8 yrs |
| Reading, PA | 1,435 | 18.1¢ | 9.3 yrs |
| Watertown, NY | 1,435 | 24.3¢ | 6.9 yrs |
| Minot, ND | 1,432 | 11.1¢ | 15.2 yrs |
Nearby cities
See all of New Hampshire → statewide sunlight, rates, incentives and every city we've measured.
Keene solar questions
How many solar panels do I need in Keene?
About 23 panels for an average home using 10,800 kWh a year. Keene roofs get 1,434 usable sun hours, so each 400W panel produces roughly 488 kWh annually. A typical Keene roof fits about 38 panels, so check your usable roof area before assuming that many will fit.
Is solar worth it in Keene?
At 25.3¢/kWh and 1,434 sun hours, a typical system pays for itself in about 6.7 years and returns roughly $50,610 over a 25-year panel life. That is a solid return, and it improves further if electricity prices rise. Exported power earns full retail credit here.
How much do solar panels cost in Keene?
A 9.2 kW system costs about $26,220 before incentives and $18,354 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 New Hampshire 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.