How to use the solar irradiance on a tilted surface calculator
Find the effective sunlight on a tilted panel. Enter direct irradiance, angle between sun and surface normal in the fields above; the irradiance on surface is computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- S — Direct irradiance (W/m²)
- th — Angle between sun and surface normal (°)
Worked example
With direct irradiance = 1000 W/m², angle between sun and surface normal = 30 °, the calculator gives irradiance on surface ≈ 866.0254 W/m².
Frequently asked questions
What is the formula for the solar irradiance on a tilted surface calculation?
Irradiance on surface (W/m²) = S × cos(th). Here S is direct irradiance (W/m²), th is angle between sun and surface normal (°).
What inputs do I need for the solar irradiance on a tilted surface calculator?
You need direct irradiance in W/m², angle between sun and surface normal in °. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.