Rotor Swept Area
Area swept by turbine blades, which sets its power potential.
Formula
Variables
Example
r=50 m: A ≈ 7854 m²
How it works
A wind turbine blade sweeps out a circular disk as it rotates, and this formula gives the area of that disk. The radius is the blade length, so the formula uses the standard area of a circle, πr². A larger swept area means the turbine can intercept more moving air, which generally increases the amount of wind energy available to convert into electricity.
When to use it
Use this when you need to estimate how much wind a turbine rotor can capture from its blade length. It is commonly used in renewable energy calculations, turbine comparisons, and basic power-potential estimates.
Worked example, step by step
Given: blade length r = 30 m Use the formula: A = πr² Substitute the value: A = π × (30 m)² Square the radius: A = π × 900 m² Multiply by π: A ≈ 3.1416 × 900 m² Final answer: A ≈ 2827 m²
Common mistakes to avoid
- Using the blade diameter instead of the radius
- Forgetting to square the blade length before multiplying by π
- Leaving the answer in metres instead of square metres (m²)
Did You Know?
Doubling blade length quadruples the swept area — why modern turbines keep growing ever larger.
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