Wind Turbine Payback in Marshall County, MS
Wind turbine payback in Marshall 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 Marshall County, MS averages 4.35 m/s (9.7 mph). A 10 kW turbine there would make about 8,460 kWh a year, worth $1,274 at MS's 15.06¢/kWh. Against an installed cost of about $100,000, that is a payback of 79 years, and the turbine is built to last about 20.
What to do in Marshall County
A home turbine is not worth buying for savings in Marshall County unless your spot is far windier than the county average, 7.9 m/s at the hub against 4.35 m/s here. Per kW, solar panels would make about 1,302 kWh a year here against the turbine's 846, so get a solar quote first.
What would have to change
- Power would have to cost 59¢/kWh, 3.9 times what MS pays now.
- Or the average wind at the hub would have to be 7.9 m/s instead of 4.35. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MS
Marshall County is the 1,852nd windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MS is DeSoto County at 5.13 m/s, payback 50 years.
Month by month in Marshall County
March is the strongest month here, at 5.14 m/s and about 1,144 kWh. July is the weakest, 3.16 m/s and 262 kWh, so the best month makes 4.4 times the worst. November to March brings in 57% of the year's output in Marshall County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.01 m/s | 1,070 kWh | $161 |
| February | 5.13 m/s | 1,029 kWh | $155 |
| March | 5.14 m/s | 1,144 kWh | $172 |
| April | 5.14 m/s | 1,107 kWh | $167 |
| May | 4.26 m/s | 676 kWh | $102 |
| June | 3.56 m/s | 374 kWh | $56 |
| July | 3.16 m/s | 262 kWh | $39 |
| August | 3.22 m/s | 281 kWh | $42 |
| September | 3.78 m/s | 452 kWh | $68 |
| October | 4.27 m/s | 680 kWh | $102 |
| November | 4.71 m/s | 875 kWh | $132 |
| December | 4.81 m/s | 955 kWh | $144 |
What a taller tower would buy
Measured at 10 m the wind in Marshall County averages 3.07 m/s; at 50 m it is 5.11 m/s. That gives a shear exponent of 0.317, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 5,715 to 13,284 kWh a year, 132% 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 | 3.82 m/s | 5,715 kWh | over 100 years |
| 30 m | 4.35 m/s | 8,437 kWh | 79 years |
| 40 m | 4.76 m/s | 10,960 kWh | 61 years |
| 50 m | 5.11 m/s | 13,284 kWh | 50 years |
Counties around Marshall County
2 of the 6 closest counties are windier at turbine height; the windiest, DeSoto County, averages 5.13 m/s.
- Benton County, MS: 4.35 m/s, 8,460 kWh, payback 79 years (18 mi)
- Tate County, MS: 4.85 m/s, 11,537 kWh, payback 58 years (26 mi)
- Lafayette County, MS: 3.81 m/s, 5,660 kWh, payback over 100 years (29 mi)
- DeSoto County, MS: 5.13 m/s, 13,421 kWh, payback 50 years (29 mi)
- Fayette County, TN: 4.35 m/s, 8,460 kWh, payback 86 years (30 mi)
- Tippah County, MS: 3.47 m/s, 4,211 kWh, payback over 100 years (33 mi)
Sun versus wind in Marshall County
Marshall County gets 4.46 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,302 kWh a year; one kW of the turbine above makes 846. Kilowatt for kilowatt, panels make 1.5 times as much here as the turbine. 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.