Solar panels in Williamsport, PA
Roofs in Williamsport get about 1,280 hours of usable sunlight a year — less than 81% 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 Williamsport → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Williamsport solar system costs
A 25-panel system (10 kW) is about right for an average Williamsport home using 10,800 kWh a year. It would produce roughly 10,880 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,482 | $6,384 | $630 | 10.1 yrs |
| 12 panels | 4.8 kW | 5,222 | $9,576 | $945 | 10.1 yrs |
| 16 panels | 6.4 kW | 6,963 | $12,768 | $1,260 | 10.1 yrs |
| 20 panels | 8 kW | 8,704 | $15,960 | $1,575 | 10.1 yrs |
| 26 panels | 10.4 kW | 11,315 | $20,748 | $1,978 | 10.5 yrs |
How we worked this out for Williamsport
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Williamsport rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,280 sun hrs × 0.85 system losses |
435 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 435 kWh per panel |
25 panels |
| 3 | System size 25 panels × 400W |
10.00 kW |
| 4 | Annual production 10.00 kW × 1,280 hrs × 0.85 |
10,880 kWh/yr |
| 5 | Installed cost 10,000 W × $2.85 per watt, then −30% federal credit |
$19,950 |
| 6 | Annual saving 3,780 kWh used as generated × 18.1¢ + 7,100 kWh exported × 18.1¢ |
$1,958/yr |
| 7 | Payback $19,950 ÷ $1,958 per year |
10.2 years |
Step 6 matters more than it looks. Only 35% of what a system this size produces in Williamsport is used the moment it is generated; the other 7,100 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 — 10.1 years against the 10.2 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, 18.1¢/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 Williamsport gets 1,280 sun hours
That figure comes from Google's analysis of real rooftops across Williamsport — 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 Williamsport reaches about 1,510 hours, roughly 18% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,280 hrs/yr |
|---|---|
| Unshaded roof | 1,510 hrs/yr |
| Electricity rate (Pennsylvania avg) | 18.1¢/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 | 8 |
| Google imagery from | 2016 |
When Williamsport actually produces
Annual totals hide the thing that catches people out: 37% of Williamsport's yearly sunlight arrives in May–July, and just 13% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 55 | |
| Feb | 76 | |
| Mar | 103 | |
| Apr | 131 | |
| May | 152 | |
| Jun | 160 | |
| Jul | 156 | |
| Aug | 139 | |
| Sep | 113 | |
| Oct | 84 | |
| Nov | 60 | |
| Dec | 50 |
Williamsport produces about 3.2× 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 Williamsport's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Williamsport compares to the other 788 cities
| Measure | Williamsport | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,280 hrs | 636th |
| Sunlight lost to shade | 15% | 16th most |
| Median roof size | 227 m² | 281st largest |
| Electricity rate | 18.1¢ | 303rd highest |
| Payback | 10.2 yrs | 355th fastest |
| Grid carbon | 654 kg/MWh | 336th dirtiest |
What actually stands out about Williamsport:
- Shading is a real problem here. Williamsport loses 15% of its potential sunlight to trees, chimneys and neighbouring buildings — the 16th-worst of the 788 cities measured. Panel placement matters more here than in most places, and a roof survey is worth more than a phone quote.
- Dimmer than the rest of Pennsylvania. Williamsport roofs get 7% less usable sunlight than the typical Pennsylvania city we've measured — statewide averages will overstate what you can expect here.
- Older imagery. Google's aerial capture of Williamsport dates from 2016. Tree growth and new construction since then are not reflected.
Cities with almost the same sunlight
These are the closest matches to Williamsport's 1,280 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 |
|---|---|---|---|
| Flint, MI | 1,288 | 19.1¢ | 9.6 yrs |
| International Falls, MN | 1,290 | 14.8¢ | 12.4 yrs |
| Augusta, ME | 1,270 | 24.8¢ | 7.7 yrs |
| Brockton, MA | 1,269 | 30.1¢ | 6.3 yrs |
Nearby cities
See all of Pennsylvania → statewide sunlight, rates, incentives and every city we've measured.
Williamsport solar questions
How many solar panels do I need in Williamsport?
About 25 panels for an average home using 10,800 kWh a year. Williamsport roofs get 1,280 usable sun hours, so each 400W panel produces roughly 435 kWh annually. A typical Williamsport roof fits about 81 panels, so roof space is unlikely to be your limit.
Is solar worth it in Williamsport?
At 18.1¢/kWh and 1,280 sun hours, a typical system pays for itself in about 10.2 years and returns roughly $29,010 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 Williamsport?
A 10 kW system costs about $28,500 before incentives and $19,950 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 Pennsylvania 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.