TurbinePayback

Wind Turbine Payback in St. Joseph County, IN

Wind turbine payback in St. Joseph 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 St. Joseph County, IN averages 5.96 m/s (13.3 mph). A 10 kW turbine there would make about 19,408 kWh a year, worth $3,307 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 30 years, and the turbine is built to last about 20.

What to do in St. Joseph County

A home turbine is not worth buying for savings in St. Joseph County unless your spot is far windier than the county average, 7.3 m/s at the hub against 5.96 m/s here. Per kW, solar panels would make about 1,113 kWh a year here against the turbine's 1,941, so get a solar quote first.

What would have to change

Against the rest of IN

St. Joseph County is the 901st windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in IN is Lake County at 6.17 m/s, payback 28 years.

Month by month in St. Joseph County

January is the strongest month here, at 6.83 m/s and about 2,193 kWh. July is the weakest, 4.53 m/s and 810 kWh, so the best month makes 2.7 times the worst. November to March brings in 52% of the year's output in St. Joseph County.

MonthWind at 30 mOutputWorth
January6.83 m/s2,193 kWh$374
February6.69 m/s1,901 kWh$324
March6.53 m/s2,005 kWh$342
April6.80 m/s2,106 kWh$359
May5.86 m/s1,585 kWh$270
June5.09 m/s1,083 kWh$185
July4.53 m/s810 kWh$138
August4.55 m/s819 kWh$140
September5.19 m/s1,138 kWh$194
October6.24 m/s1,826 kWh$311
November6.64 m/s2,010 kWh$343
December6.59 m/s2,044 kWh$348

What a taller tower would buy

Measured at 10 m the wind in St. Joseph County averages 4.64 m/s; at 50 m it is 6.69 m/s. That gives a shear exponent of 0.227, typical of ordinary open country. Going from 20 m to 50 m takes output from 15,560 to 24,801 kWh a year, 59% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.

Hub heightAverage windOutputPayback
20 m5.43 m/s15,560 kWh38 years
30 m5.96 m/s19,390 kWh30 years
40 m6.36 m/s22,370 kWh26 years
50 m6.69 m/s24,801 kWh24 years

Counties around St. Joseph County

5 of the 6 closest counties are windier at turbine height; the windiest, Berrien County, averages 6.87 m/s.

Sun versus wind in St. Joseph County

St. Joseph County gets 3.81 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,113 kWh a year; one kW of the turbine above makes 1,941. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.7 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.