Solar Panel Daily Energy Calculator
Estimated Daily Energy Generation:
Understanding Solar Insolation and Energy Generation
Solar insolation refers to the amount of solar radiation energy received on a given surface area over a given time. It's a crucial factor in determining the potential energy output of a solar panel system. While often measured in units like kWh/m²/day or MJ/m²/day, for practical solar energy calculations, it's frequently simplified to "Peak Sun Hours" (PSH).
What are Peak Sun Hours (PSH)?
Peak Sun Hours (PSH) represent the equivalent number of hours per day when solar irradiance averages 1,000 watts per square meter (W/m²). For example, if a location receives 5 kWh/m²/day of solar insolation, it's considered to have 5 Peak Sun Hours. This metric simplifies the complex variations in sunlight intensity throughout the day into a single, easy-to-use number for energy calculations.
Factors Affecting Solar Insolation and Energy Output:
- Geographic Location (Latitude): Locations closer to the equator generally receive more direct sunlight and thus higher insolation.
- Time of Year: Insolation varies significantly with seasons due to the Earth's tilt and orbit around the sun.
- Weather Conditions: Cloud cover, fog, and atmospheric haze can significantly reduce the amount of solar radiation reaching the ground.
- Panel Tilt Angle: The angle at which solar panels are tilted relative to the horizontal ground greatly impacts how much direct sunlight they receive. An optimal tilt angle maximizes energy capture.
- Panel Azimuth Angle: This refers to the direction the panels face (e.g., true South in the Northern Hemisphere, true North in the Southern Hemisphere) to maximize exposure to the sun throughout the day.
- Shading: Obstructions like trees, buildings, or chimneys can cast shadows on panels, drastically reducing their output.
- Panel Efficiency: The inherent ability of the solar panel to convert sunlight into electricity. Modern panels typically range from 17% to 22% efficiency.
- System Losses: These include various factors that reduce the overall energy output, such as temperature effects on panels, inverter efficiency, wiring losses, dust accumulation, and degradation over time. These losses can typically range from 10% to 25%.
How This Calculator Works:
This calculator estimates the potential daily energy generation of your solar panel system based on the following inputs:
- Average Daily Peak Sun Hours (kWh/m²/day): This is your local solar insolation data. You can find this information from solar maps, meteorological data, or online resources specific to your location and the time of year you're interested in.
- Total Panel Area (m²): The combined surface area of all your solar panels.
- Panel Efficiency (%): The efficiency rating of your solar panels, usually found in the product specifications.
- System Losses (%): An estimated percentage of energy lost due to various factors within the solar system (e.g., inverter, wiring, temperature, dust). A common estimate is 14-20%.
The formula used is: Daily Energy (kWh) = Peak Sun Hours * Panel Area * (Panel Efficiency / 100) * (1 - System Losses / 100)
Example Calculation:
Let's say you have a solar system with:
- Average Daily Peak Sun Hours: 5 kWh/m²/day
- Total Panel Area: 10 m²
- Panel Efficiency: 20%
- System Losses: 15%
Using the formula:
Daily Energy = 5 kWh/m²/day * 10 m² * (20 / 100) * (1 - 15 / 100)
Daily Energy = 5 * 10 * 0.20 * 0.85
Daily Energy = 8.5 kWh
This means your system could potentially generate 8.5 kilowatt-hours of electricity per day under these conditions.