Solar panels in Green Bay, WI
Roofs in Green Bay get about 1,444 hours of usable sunlight a year — less than 60% 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 Green Bay → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Green Bay solar system costs
A 22-panel system (8.8 kW) is about right for an average Green Bay home using 10,800 kWh a year. It would produce roughly 10,801 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,928 | $6,384 | $679 | 9.4 yrs |
| 12 panels | 4.8 kW | 5,892 | $9,576 | $1,019 | 9.4 yrs |
| 16 panels | 6.4 kW | 7,855 | $12,768 | $1,359 | 9.4 yrs |
| 20 panels | 8 kW | 9,819 | $15,960 | $1,699 | 9.4 yrs |
| 26 panels | 10.4 kW | 12,765 | $20,748 | $1,953 | 10.6 yrs |
How we worked this out for Green Bay
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Green Bay rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,444 sun hrs × 0.85 system losses |
491 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 491 kWh per panel |
22 panels |
| 3 | System size 22 panels × 400W |
8.80 kW |
| 4 | Annual production 8.80 kW × 1,444 hrs × 0.85 |
10,801 kWh/yr |
| 5 | Installed cost 8,800 W × $2.85 per watt, then −30% federal credit |
$17,556 |
| 6 | Annual saving 3,780 kWh used as generated × 17.3¢ + 7,021 kWh exported × 17.3¢ |
$1,868/yr |
| 7 | Payback $17,556 ÷ $1,868 per year |
9.4 years |
Step 6 matters more than it looks. Only 35% of what a system this size produces in Green Bay is used the moment it is generated; the other 7,021 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 — 9.4 years against the 9.4 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, 17.3¢/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 Green Bay gets 1,444 sun hours
That figure comes from Google's analysis of real rooftops across Green Bay — 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 Green Bay reaches about 1,541 hours, roughly 7% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,444 hrs/yr |
|---|---|
| Unshaded roof | 1,541 hrs/yr |
| Electricity rate (Wisconsin avg) | 17.3¢/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 | 35% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 11 |
| Google imagery from | 2024 |
When Green Bay actually produces
Annual totals hide the thing that catches people out: 38% of Green Bay's yearly sunlight arrives in May–July, and just 12% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 56 | |
| Feb | 81 | |
| Mar | 115 | |
| Apr | 151 | |
| May | 178 | |
| Jun | 189 | |
| Jul | 183 | |
| Aug | 161 | |
| Sep | 128 | |
| Oct | 91 | |
| Nov | 62 | |
| Dec | 50 |
Green Bay produces about 3.8× 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 Green Bay's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Green Bay compares to the other 788 cities
| Measure | Green Bay | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,444 hrs | 474th |
| Sunlight lost to shade | 6% | 266th most |
| Median roof size | 278 m² | 162nd largest |
| Electricity rate | 17.3¢ | 310th highest |
| Payback | 9.4 yrs | 290th fastest |
| Grid carbon | 794 kg/MWh | 156th dirtiest |
What actually stands out about Green Bay:
- Plenty of roof to work with. Typical roofs here fit around 102 panels — roughly 4× what an average home needs. Roof size will not be what limits your system in Green Bay.
Cities with almost the same sunlight
These are the closest matches to Green Bay's 1,444 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 |
|---|---|---|---|
| Worcester, MA | 1,443 | 30.1¢ | 5.6 yrs |
| Dearborn, MI | 1,445 | 19.1¢ | 8.5 yrs |
| Boston, MA | 1,446 | 30.1¢ | 5.4 yrs |
| Harrisburg, PA | 1,446 | 18.1¢ | 9 yrs |
Nearby cities
See all of Wisconsin → statewide sunlight, rates, incentives and every city we've measured.
Green Bay solar questions
How many solar panels do I need in Green Bay?
About 22 panels for an average home using 10,800 kWh a year. Green Bay roofs get 1,444 usable sun hours, so each 400W panel produces roughly 491 kWh annually. A typical Green Bay roof fits about 102 panels, so roof space is unlikely to be your limit.
Is solar worth it in Green Bay?
At 17.3¢/kWh and 1,444 sun hours, a typical system pays for itself in about 9.4 years and returns roughly $29,155 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 Green Bay?
A 8.8 kW system costs about $25,080 before incentives and $17,556 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 Wisconsin 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.