Skip to main contentShading models calculate irradiance reduction from geometric obstructions between the sun and the PV modules. PlantPredict applies shading in a specific sequence and offers multiple approaches for different shading scenarios.
Models in This Section
Horizon Shading
Far-field shading from terrain features and distant obstructions. Applied to the beam component before near-field geometric shading.
Diffuse Shading
Sky-view factor reduction using the Schaar-Panchula methodology. Accounts for obstruction of diffuse sky irradiance by nearby rows.
Direct Beam Shading
Near-field shading from row-to-row and structural obstructions:
- Linear Shading (2D): IRIS model for standard row-to-row shading on flat terrain
- 3D Shading - DC Field Level (Legacy): Ray-tracing approach for complex DC field geometry, limited to single DC field scope
- 3D Shading - Site Level (Version 12+): Polygon clipping algorithm for full site-level 3D shading with broad-phase and narrow-phase collision detection (automatically enabled with 3D scene)
Electrical Effect of Shading
Converts geometric shade fraction to electrical power loss:
- None: No electrical effect applied
- Linear: Direct proportional loss
- Fractional: Cell-level shading with bypass diode effects
- Step-Fractional: Discrete steps based on shaded cell count
Application Sequence
- Horizon Shading (beam component)
- Diffuse Shading (diffuse component)
- Direct Beam Shading (beam component)
- Electrical Effect of Shading (DC power)
Soiling losses are documented in the Plane-of-Array Irradiance section as they represent optical losses rather than geometric shading. 
