Solar Panel Efficiency Calculator

Calculate the efficiency of your solar panels based on their power output, physical area, and the solar irradiance they receive. This helps you understand how well your panels convert sunlight into electricity.

Maximum power output of the panel under standard test conditions
Typical residential panel length is 65-67 inches
Typical residential panel width is 39-40 inches
Standard test conditions use 1000 W/m²
Standard test conditions use 25°C

How to Use This Calculator

  1. Enter Power Output: Input the maximum power output of your solar panel in watts.
  2. Panel Dimensions: Enter the length and width of your panel in inches.
  3. Solar Conditions: Specify the solar irradiance and temperature.
  4. Calculate: Click the button to see your panel's efficiency.

Typical Panel Efficiencies

Panel Type Typical Efficiency Temperature Coefficient
Monocrystalline 15-22% -0.4 to -0.5%/°C
Polycrystalline 13-16% -0.4 to -0.5%/°C
Thin-Film 10-13% -0.25%/°C

Important Considerations:

  • Efficiency varies with temperature and solar irradiance
  • Real-world efficiency is typically lower than laboratory conditions
  • Dust, dirt, and shading can significantly reduce efficiency
  • Panel efficiency degrades over time
  • Consider temperature coefficient for your climate
  • Higher efficiency panels are generally more expensive

For professional installations, consult with a solar expert to verify calculations and consider site-specific factors.