Calculating solar panel efficiency can be done using a simple formula:
Solar Panel Efficiency (%) = (Electrical Output Power / Solar Energy Input) × 100
Here’s how to calculate solar panel efficiency quickly.
- Determine the electrical output power of your solar panel. This is the actual electrical power generated by the panel and is usually provided by the manufacturer in watts (W).
- Measure the solar energy input, which is the amount of sunlight that hits the solar panel. You can use a solar irradiance measurement in watts per square meter (W/m²) for a specific location and time.
- Plug the values into the formula and calculate the efficiency in percentage.
For example, if your solar panel generates 300 watts of electrical power and receives 1,000 W/m² of solar energy input, the efficiency would be:
Solar Panel Efficiency = (300 W / 1000 W/m²) × 100 = 30%
Keep in mind that solar panel efficiency can vary based on factors such as the type of panel, environmental conditions, and temperature. Manufacturers typically provide efficiency ratings for their panels under standard test conditions (STC), which may not always reflect real-world performance. Actual efficiency can vary from day to day and season to season due to factors like shading, soiling, and temperature variations.
