1. What is the Power Formula in Terms of Velocity?

Definition: This formula calculates the power available in wind based on air density, swept area, and wind velocity.

Purpose: It's primarily used in wind energy calculations to determine the potential power generation from wind turbines.

2. How Does the Formula Work?

The formula is:

Where:

• \( P \) — Power (Watts)
• \( \rho \) — Air density (kg/m³)
• \( A \) — Swept area (m²)
• \( v \) — Wind velocity (m/s)

Explanation: The power increases with the cube of wind velocity, making higher wind speeds dramatically more powerful.

3. Importance of the Power Calculation

Details: Accurate power calculation helps in designing efficient wind turbines and estimating potential energy production.

4. Using the Calculator

Tips: Enter air density (default 1.225 kg/m³ at sea level), swept area, and wind velocity. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is velocity cubed in the formula?
A: The kinetic energy of wind depends on velocity squared, and the rate of energy delivery (power) adds another velocity factor.

Q2: What's a typical air density value?
A: At sea level and 15°C, it's approximately 1.225 kg/m³. Density decreases with altitude and increases with lower temperatures.

Q3: How does swept area affect power?
A: Power is directly proportional to the area swept by the turbine blades. Doubling the area doubles the power.

Q4: What's the practical maximum efficiency?
A: The Betz limit states that no turbine can capture more than 59.3% of the wind's kinetic energy.

Q5: How does this relate to real wind turbines?
A: This gives the theoretical maximum power. Actual power is less due to efficiency factors, mechanical losses, and other constraints.