Turbine Spacing Calculator
Estimate how many turbines fit on a site using standard wake-spacing rules of thumb.
Wind turbines extract energy from the air passing through their rotors. Immediately downwind, they leave a wake: a region of slower, more turbulent air that recovers gradually with distance. If the next row of turbines is placed too close, it operates in the wake of the row in front, suffering reduced energy capture and increased fatigue loads. Spacing turbines adequately apart is therefore a fundamental wind farm design constraint.
Industry rules of thumb suggest placing turbines roughly 7–10 rotor diameters (D) apart in the prevailing wind direction and 3–5 D apart crosswind. This tool applies those multipliers to a rectangular site to estimate how many turbines fit in a simple grid layout and the total installed capacity. Real wind farm layouts are almost never simple grids: they are optimised using wake models and wind rose data, and shaped by terrain, planning constraints and access roads. Use this tool to build intuition, not to plan an actual project.
Turbine spacing result
Spacing rules of thumb (7 D downwind, 4 D crosswind) reduce wake energy losses to roughly 5–10 % in a regular grid. Real wind farm layouts are optimised for specific wind rose data, terrain and planning constraints and often use irregular arrangements. This is an educational estimation only.
How to use this tool
- Enter the rotor diameter in metres.
- Set the downwind and crosswind spacing multipliers (rotor diameters). The defaults of 7 D and 4 D are common starting points.
- Enter the site dimensions in kilometres — length along the prevailing wind direction and width across it.
- Enter the rated capacity per turbine in MW.
- Press Calculate to see the number of turbines, grid layout, spacing in metres, and total capacity.
💡 Good to know
All calculations use standard, published formulas and simplified assumptions so beginners can build intuition. For real projects, always consult qualified engineers and site-specific data.
Frequently asked questions
Why is downwind spacing larger than crosswind spacing?
Wakes are elongated in the wind direction and recover slowly. Ten rotor diameters downwind, a wake may still carry 10–20 % less wind energy than free-stream. Crosswind, the wake dissipates more quickly, so turbines can be spaced closer without significant energy loss.
Does this tool account for wake losses?
No. It calculates how many turbines fit on a rectangular site using fixed spacing rules, but it does not model the actual energy loss from wakes. Real wake losses depend on the wind direction distribution, turbine operating point and the specific spacing. For a full wind farm energy yield, specialist software such as WAsP, WindSim or Openwind is used.
What if the site is not rectangular?
This tool assumes a simple rectangular site. Irregular sites, hillsides, coastal headlands and sites with exclusion zones (roads, buildings, ecology) need bespoke layout optimisation. The result here is an upper-bound estimate for a flat rectangular site.
Why do some offshore farms use wider spacing?
Offshore, land cost is not a constraint in the same way, and larger turbines with longer wakes are used. Some offshore projects use spacings of 8–12 D downwind to further reduce wake losses and fatigue loading, improving long-term energy yield.