Wind Turbine Payback in Cumberland County, NJ
Wind turbine payback in Cumberland 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 Cumberland County, NJ averages 5.8 m/s (13 mph). A 10 kW turbine there would make about 18,226 kWh a year, worth $4,391 at NJ's 24.09¢/kWh. Against an installed cost of about $100,000, that is a payback of 23 years, and the turbine is built to last about 20.
What to do in Cumberland County
A home turbine is not worth buying for savings in Cumberland County unless your spot is far windier than the county average, 6.1 m/s at the hub against 5.8 m/s here. Per kW, solar panels would make about 1,188 kWh a year here against the turbine's 1,823, so get a solar quote first.
What would have to change
- Power would have to cost 27¢/kWh, 1.1 times what NJ pays now.
- Or the average wind at the hub would have to be 6.1 m/s instead of 5.8. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of NJ
Cumberland County is the 1,064th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in NJ is Cape May County at 6.6 m/s, payback 17 years.
Month by month in Cumberland County
March is the strongest month here, at 6.62 m/s and about 2,065 kWh. August is the weakest, 4.51 m/s and 797 kWh, so the best month makes 2.6 times the worst. November to March brings in 53% of the year's output in Cumberland County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.54 m/s | 2,015 kWh | $485 |
| February | 6.67 m/s | 1,890 kWh | $455 |
| March | 6.62 m/s | 2,065 kWh | $497 |
| April | 6.47 m/s | 1,908 kWh | $460 |
| May | 5.50 m/s | 1,364 kWh | $329 |
| June | 5.02 m/s | 1,040 kWh | $251 |
| July | 4.60 m/s | 847 kWh | $204 |
| August | 4.51 m/s | 797 kWh | $192 |
| September | 5.09 m/s | 1,080 kWh | $260 |
| October | 5.97 m/s | 1,655 kWh | $399 |
| November | 6.25 m/s | 1,774 kWh | $427 |
| December | 6.40 m/s | 1,927 kWh | $464 |
What a taller tower would buy
Measured at 10 m the wind in Cumberland County averages 4.43 m/s; at 50 m it is 6.58 m/s. That gives a shear exponent of 0.246, typical of ordinary open country. Going from 20 m to 50 m takes output from 14,271 to 23,996 kWh a year, 68% 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 | 5.25 m/s | 14,271 kWh | 29 years |
| 30 m | 5.8 m/s | 18,248 kWh | 23 years |
| 40 m | 6.23 m/s | 21,399 kWh | 19 years |
| 50 m | 6.58 m/s | 23,996 kWh | 17 years |
Counties around Cumberland County
2 of the 6 closest counties are windier at turbine height; the windiest, Cape May County, averages 6.6 m/s.
- Salem County, NJ: 5.23 m/s, 14,116 kWh, payback 29 years (21 mi)
- Cape May County, NJ: 6.6 m/s, 24,142 kWh, payback 17 years (22 mi)
- Kent County, DE: 5.7 m/s, 17,492 kWh, payback 32 years (26 mi)
- Gloucester County, NJ: 5.8 m/s, 18,226 kWh, payback 23 years (27 mi)
- Atlantic County, NJ: 6.47 m/s, 23,186 kWh, payback 18 years (28 mi)
- New Castle County, DE: 5.23 m/s, 14,116 kWh, payback 39 years (33 mi)
Sun versus wind in Cumberland County
Cumberland County gets 4.07 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,188 kWh a year; one kW of the turbine above makes 1,823. 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.