METEOROLOGY – OLAR RADIATION CALCULATOR
Global Horizontal Irradiance
A precise tool.
What is the Global Horizontal Irradiance & How does it work?
Global Horizontal Irradiance (GHI) is the total amount of solar radiation received on a horizontal surface over a given period, typically expressed in watts per square meter (W/mΒ²). It includes both direct sunlight from above and diffuse sunlight scattered by the atmosphere.
The GHI can be calculated using the formula: [ GHI = DNI cdot cos(theta) + DIF ] where
DNI
DNI = Direct Normal Irradiance (W/mΒ²)
theta
theta = Solar Zenith Angle (degrees)
DIF
DIF = Diffuse Irradiance (W/mΒ²)
Understanding GHI is crucial for applications such as solar energy systems, agriculture, and climate studies.
Parameters
Result
β
Frequently Asked Questions
What is Global Horizontal Irradiance (GHI)?
Global Horizontal Irradiance is the total solar radiation received on a horizontal surface, including direct sunlight and diffuse sky radiation.
How do I calculate GHI?
Use the formula: GHI = DNI * cos(ΞΈ) + DIF, where DNI is Direct Normal Irradiance, ΞΈ is Solar Zenith Angle, and DIF is Diffuse Irradiance.
What units are used for GHI?
GHI is typically expressed in watts per square meter (W/mΒ²).
Why is the Solar Zenith Angle important in GHI calculation?
The Solar Zenith Angle affects how much direct sunlight reaches a horizontal surface, influencing the overall GHI.
Can I use this calculator for any location?
This calculator provides a general formula; specific values for DNI and DIF may vary by location and time of year.
What is the difference between Direct Normal Irradiance (DNI) and Diffuse Irradiance (DIF)?
DNI is the intensity of direct sunlight from above, while DIF is the solar radiation scattered by the atmosphere reaching a horizontal surface.
How does weather affect GHI?
Weather conditions such as clouds and atmospheric turbidity can significantly reduce GHI by blocking or scattering more sunlight.
Results are for informational purposes only and do not constitute professional advice.