Small Cabin
- Rotor
- 4 ft diameter
- Wind
- 8 mph average
- Tower
- 40 ft
~35 kWh/mo
Enough for LED lights, a laptop, phone charging, and a small fridge. A good match for a weekend cabin or hunting camp.
Find Out What a Backyard Wind Turbine Can Actually Power
Enter your rotor size, wind speed, and tower height. Get a realistic monthly energy estimate in seconds, with no hype and no sales pitch.
Your Turbine Setup
ft
Most DIY turbines use rotors between 3 and 12 feet. Larger rotors capture more wind but need stronger towers.
mph
Use a local weather station or wind maps for your area. Measure at the height you plan to mount the turbine.
ft
Taller towers reach faster, smoother wind. A 60-foot tower is a common starting point for small turbines.
Cp
The Betz limit is 0.59. Most small turbines achieve 0.20 to 0.35. Leave at 0.30 unless you know your turbine's spec sheet.
Saved Setups
No saved setups yet. Adjust the values above and click Save to store a configuration.
What Could This Power?
Here is how your estimated monthly output stacks up against common household loads. A small turbine rarely runs a whole house alone, but it can meaningfully offset your usage.
| Appliance / Load | Monthly kWh | % of Your Output | Hours / Month |
|---|
Values are estimates based on typical usage. Your actual loads may vary. LED lighting and efficient refrigerators use less; older appliances and electric heating use more.
Example Setups
Three common situations to give you a feel for what different configurations produce. Click any scenario to load it into the calculator above.
Homestead Array
- Rotor
- 8 ft diameter
- Wind
- 11 mph average
- Tower
- 80 ft
~280 kWh/mo
Can cover most lighting, refrigeration, and electronics for a small home. Pair with solar for a solid off-grid system.
Open Pasture
- Rotor
- 12 ft diameter
- Wind
- 13 mph average
- Tower
- 100 ft
~620 kWh/mo
Strong output for a rural property. Could handle a well pump, workshop tools, and most household loads except electric heating.
The Math Behind the Estimate
This calculator uses the standard wind power equation:
P = 0.5 × ρ × A × V³ × Cp
Where ρ (air density) ≈ 1.225 kg/m³, A is rotor swept area, V is wind speed in m/s, and Cp is the power coefficient (efficiency).
The result is average power in watts. Multiply by 730 hours per month for kWh. The capacity factor shown compares your average output to the theoretical maximum at your rotor size.
This is the same formula used in academic wind energy courses. It is not a manufacturer's marketing number.
Common Mistakes When Sizing a Turbine
- Using rated power as average. A "1000W turbine" peaks at 1000W in high wind. At 10 mph average, expect 100 to 200W continuous.
- Ignoring tower height. Wind speed increases with height. A 30-foot tower in a wooded area may see half the wind of an 80-foot tower on open ground.
- Trusting manufacturer output charts. Many charts show output at ideal conditions. Ask for the power curve at your average wind speed, not the peak.
- Forgetting turbulence. Trees, buildings, and hills create choppy wind that reduces output and wears out turbines faster. Mount above nearby obstructions.
- Skipping the charge controller. A turbine without a proper controller can overcharge batteries or dump power into a load that cannot handle it.
Before You Buy Anything
Spend at least one month measuring wind at your planned tower height with a cheap anemometer. Free data from weather stations is helpful but often measured at 33 feet and may not reflect your site.
Check local zoning laws. Some areas restrict tower height or require permits for structures over 35 feet. Homeowner associations may have additional rules.
Consider starting with solar if your average wind is below 7 mph. Solar panels have no moving parts, need less maintenance, and produce more predictable output in low-wind areas.
Frequently Asked Questions
- What wind speed do I need for a small turbine to make sense?
- Most small turbines start producing useful power around 7 to 9 mph. Below 6 mph, solar is usually a better investment. The sweet spot is 10 to 14 mph at hub height with few obstructions.
- Can I power my whole house with one backyard turbine?
- A single small turbine typically produces 50 to 300 kWh per month. The average US home uses about 900 kWh. A turbine can offset a meaningful portion, but full independence usually needs solar or a larger system.
- How accurate is this estimator?
- It uses the standard wind power equation with a realistic efficiency factor. Most users report actual output within 15 to 25 percent of the estimate. It is more honest than manufacturer claims.
- What is the difference between rated and actual output?
- Rated power is the peak at high wind speed (often 25 to 28 mph). At a typical 10 mph average, a 1000W turbine might produce 100 to 200W on average. This estimator uses average wind speed.
Why This Exists
Small wind turbine sellers are not known for honest output claims. Most advertise peak power at wind speeds you will never see on a typical homestead. This estimator uses the same physics formula taught in wind energy courses, with realistic efficiency numbers, so you can plan with real data instead of marketing hype.
It was built for off-grid hobbyists, rural homeowners, and anyone who wants to know what a turbine can actually do before spending thousands on equipment. Bookmark it, save your setups, and compare configurations as you research real hardware.
Version 1.0 · Updated 2026 · Assumes standard air density at sea level. Output decreases at higher altitudes.