Wind Turbine Payback in Assumption Parish, LA
Wind turbine payback in Assumption Parish
No. The turbine wears out before it pays for itself.
At 30 m, the height a home turbine tower usually reaches, the wind in Assumption Parish, LA averages 4.84 m/s (10.8 mph). A 10 kW turbine there would make about 11,472 kWh a year, worth $1,522 at LA's 13.27¢/kWh. Against an installed cost of about $100,000, that is a payback of 66 years, and the turbine is built to last about 20.
What to do in Assumption Parish
A home turbine is not worth buying for savings in Assumption Parish unless your spot is far windier than the county average, 8.6 m/s at the hub against 4.84 m/s here. Per kW, solar panels would make about 1,402 kWh a year here against the turbine's 1,147, so get a solar quote first.
What would have to change
- Power would have to cost 44¢/kWh, 3.3 times what LA pays now.
- Or the average wind at the hub would have to be 8.6 m/s instead of 4.84. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of LA
Assumption Parish is the 1,534th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in LA is Iberia Parish at 5.86 m/s, payback 40 years.
Month by month in Assumption Parish
January is the strongest month here, at 5.64 m/s and about 1,446 kWh. July is the weakest, 3.52 m/s and 375 kWh, so the best month makes 3.9 times the worst. November to March brings in 57% of the year's output in Assumption Parish.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.64 m/s | 1,446 kWh | $192 |
| February | 5.71 m/s | 1,345 kWh | $178 |
| March | 5.57 m/s | 1,402 kWh | $186 |
| April | 5.57 m/s | 1,362 kWh | $181 |
| May | 4.76 m/s | 932 kWh | $124 |
| June | 3.93 m/s | 511 kWh | $68 |
| July | 3.52 m/s | 375 kWh | $50 |
| August | 3.55 m/s | 384 kWh | $51 |
| September | 4.18 m/s | 619 kWh | $82 |
| October | 4.80 m/s | 952 kWh | $126 |
| November | 5.26 m/s | 1,176 kWh | $156 |
| December | 5.56 m/s | 1,397 kWh | $185 |
What a taller tower would buy
Measured at 10 m the wind in Assumption Parish averages 3.68 m/s; at 50 m it is 5.49 m/s. That gives a shear exponent of 0.249, typical of ordinary open country. Going from 20 m to 50 m takes output from 8,575 to 15,965 kWh a year, 86% 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 | 4.37 m/s | 8,575 kWh | 88 years |
| 30 m | 4.83 m/s | 11,434 kWh | 66 years |
| 40 m | 5.19 m/s | 13,860 kWh | 54 years |
| 50 m | 5.49 m/s | 15,965 kWh | 47 years |
Counties around Assumption Parish
2 of the 6 closest counties are windier at turbine height; the windiest, St. Mary Parish, averages 5.5 m/s.
- St. James Parish, LA: 4.7 m/s, 10,571 kWh, payback 71 years (18 mi)
- Ascension Parish, LA: 4.7 m/s, 10,571 kWh, payback 71 years (23 mi)
- St. Mary Parish, LA: 5.5 m/s, 16,037 kWh, payback 47 years (30 mi)
- Iberville Parish, LA: 4.13 m/s, 7,248 kWh, payback over 100 years (31 mi)
- St. Martin Parish, LA: 5.19 m/s, 13,837 kWh, payback 55 years (36 mi)
- St. John the Baptist Parish, LA: 4.7 m/s, 10,571 kWh, payback 71 years (38 mi)
Sun versus wind in Assumption Parish
Assumption Parish gets 4.8 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,402 kWh a year; one kW of the turbine above makes 1,147. Kilowatt for kilowatt, panels make 1.2 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.