Wind Turbine Payback in Washington County, MN
Wind turbine payback in Washington County
No. The turbine wears out before it pays for itself.
At 30 m, the height a home turbine tower usually reaches, the wind in Washington County, MN averages 5.52 m/s (12.3 mph). A 10 kW turbine there would make about 16,181 kWh a year, worth $2,660 at MN's 16.44¢/kWh. Against an installed cost of about $100,000, that is a payback of 38 years, and the turbine is built to last about 20.
What to do in Washington County
A home turbine is not worth buying for savings in Washington County unless your spot is far windier than the county average, 7.5 m/s at the hub against 5.52 m/s here. Per kW, solar panels would make about 1,110 kWh a year here against the turbine's 1,618, so get a solar quote first.
What would have to change
- Power would have to cost 31¢/kWh, 1.9 times what MN pays now.
- Or the average wind at the hub would have to be 7.5 m/s instead of 5.52. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Washington County is the 1,207th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MN is Lincoln County at 6.68 m/s, payback 25 years.
Month by month in Washington County
April is the strongest month here, at 6.16 m/s and about 1,716 kWh. July is the weakest, 4.55 m/s and 818 kWh, so the best month makes 2.1 times the worst. November to March brings in 47% of the year's output in Washington County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.93 m/s | 1,630 kWh | $268 |
| February | 6.03 m/s | 1,527 kWh | $251 |
| March | 5.93 m/s | 1,630 kWh | $268 |
| April | 6.16 m/s | 1,716 kWh | $282 |
| May | 5.67 m/s | 1,466 kWh | $241 |
| June | 5.09 m/s | 1,081 kWh | $178 |
| July | 4.55 m/s | 818 kWh | $134 |
| August | 4.56 m/s | 823 kWh | $135 |
| September | 5.35 m/s | 1,232 kWh | $203 |
| October | 5.70 m/s | 1,488 kWh | $245 |
| November | 5.73 m/s | 1,455 kWh | $239 |
| December | 5.62 m/s | 1,433 kWh | $236 |
What a taller tower would buy
Measured at 10 m the wind in Washington County averages 4.14 m/s; at 50 m it is 6.31 m/s. That gives a shear exponent of 0.262, typical of ordinary open country. Going from 20 m to 50 m takes output from 12,288 to 22,003 kWh a year, 79% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.
| Hub height | Average wind | Output | Payback |
|---|---|---|---|
| 20 m | 4.96 m/s | 12,288 kWh | 50 years |
| 30 m | 5.52 m/s | 16,178 kWh | 38 years |
| 40 m | 5.95 m/s | 19,346 kWh | 31 years |
| 50 m | 6.31 m/s | 22,003 kWh | 28 years |
Counties around Washington County
5 of the 6 closest counties are windier at turbine height; the windiest, Dakota County, averages 6.17 m/s.
- Ramsey County, MN: 5.52 m/s, 16,181 kWh, payback 38 years (10 mi)
- St. Croix County, WI: 5.94 m/s, 19,260 kWh, payback 27 years (22 mi)
- Anoka County, MN: 5.96 m/s, 19,408 kWh, payback 31 years (24 mi)
- Dakota County, MN: 6.17 m/s, 20,965 kWh, payback 29 years (27 mi)
- Hennepin County, MN: 6.05 m/s, 20,075 kWh, payback 30 years (29 mi)
- Pierce County, WI: 6.14 m/s, 20,742 kWh, payback 25 years (31 mi)
Sun versus wind in Washington County
Washington County gets 3.8 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,110 kWh a year; one kW of the turbine above makes 1,618. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.5 times. Panel output assumes an 80% system performance ratio. Wind or solar runs the same comparison for every county.
How this is worked out
Wind is NASA's Power climate record, the 2001-2025 average at 10 m and 50 m for the county's centre, carried to 30 m with this county's own measured wind shear and spread into hours with a Rayleigh distribution. The turbine is a generic 10 kW, 7 m rotor machine with 10% losses. Cost is $10,000 per kW installed with no tax credit, because the federal one ended in 2025. One county-centre number cannot see your hilltop or your tree line, so treat it as the starting point for a site survey, not a substitute. The full method and its weak spots are in how the numbers are made.