Solar panels in Wisconsin: payback, production and savings
In Milwaukee, each kW of south-facing panels produces about 1,334 kWh a year, #34 of 51 states for sunshine. Homes in Wisconsin paid 19.06¢/kWh on average in July 2026 (#18 highest in the U.S.; national average 18.31¢), up 4.4% from a year earlier. Above-average power prices make every solar kWh worth more here.
Output by month (kWh per kW)
Jul is the best month (158 kWh) and Dec the weakest (65 kWh).
Example: 7 kW system, 10,500 kWh/yr home
| Full net metering | Credit ½ retail | Credit ¼ retail | |
|---|---|---|---|
| Year-1 savings | $1,780 | $1,290 | $1,045 |
| Payback | 11.2 years | 15.0 years | 17.9 years |
| 25-year net gain | $33,430 | $18,637 | $11,241 |
Assumptions, not quotes: $21,000 installed ($3,000/kW), no incentives, 40% of use during daylight, power prices +2.5%/yr. Change them below.
How roof direction changes output in Wisconsin
kWh per kW per year, and the difference vs. south at 20°.
| Facing | 20° pitch | 30° pitch |
|---|---|---|
| South | 1,334 (+0%) | 1,373 (+3%) |
| Southeast | 1,274 (-5%) | 1,292 (-3%) |
| Southwest | 1,277 (-4%) | 1,296 (-3%) |
| East | 1,126 (-16%) | 1,091 (-18%) |
| West | 1,131 (-15%) | 1,098 (-18%) |
| East-west (split) | 1,129 (-15%) | 1,095 (-18%) |
What to check before going solar in Wisconsin
- How your utility credits exports. Net metering rules differ by state and by utility, and several states have moved to lower "net billing" credits worth a fraction of the retail rate. The example table shows three cases; look up your utility's current program in the DSIRE database.
- Federal tax credit. The 30% residential clean energy credit does not apply to systems placed in service after December 31, 2025 (IRS). Count only state or utility incentives that are still open.
- Your real price per kWh. Divide your bill's energy and delivery charges by the kWh used; fixed monthly fees don't go away with solar.
Run your own numbers in Wisconsin
First-year savings
$1,780
Payback
11.2 years
25-year net gain
$33,430
Return (IRR)
8.2%
Production vs. use by month
9,340 kWh/yr produced · covers 40% of your use directly · 45% of output used on the spot.
Which size pays off best?
Same usage and prices, only size changes. Best 25-year net gain: 8 kW.
| kW | Cost | Year-1 savings | Payback | 25-yr gain |
|---|---|---|---|---|
| 3 | $9,000 | $763 | 12.0 years | $12,899 |
| 4 | $12,000 | $1,017 | 11.6 years | $18,032 |
| 5 | $15,000 | $1,272 | 11.4 years | $23,164 |
| 6 | $18,000 | $1,526 | 11.3 years | $28,297 |
| 7 | $21,000 | $1,780 | 11.2 years | $33,430 |
| 8 | $24,000 | $2,001 | 11.2 years | $38,489 |
| 10 | $30,000 | $2,001 | 13.4 years | $35,860 |
| 12 | $36,000 | $2,001 | 15.6 years | $29,860 |
States with similar sunshine
Data: NLR PVWatts v8 (U.S. DOE National Laboratory of the Rockies, formerly NREL), TMY weather for Milwaukee (43.04, -87.91), 14% losses, retrieved 2026-10-11. Prices: U.S. EIA Electric Power Monthly, Table 5.6.A (July 2026). Methodology.