Shading and sun-path analysis

Animate the sun across the year to see which modules sit in shade and when, then apply the resulting loss to the yield simulation.

Shading analysis lives behind the Shading control at the bottom-left of the 3D editor. It splits into two views. The Sun path analysis (this page) animates the sun across a chosen day so you can watch trees, neighbouring buildings, and chimneys move their shadows over the modules. The Sun heatmap scores each module's solar quality. This page covers the sun-path side and how the loss feeds the simulation.

Note: Shading analysis is part of the residential 3D planning path. It needs 3D height data to be meaningful.

Before you start

You need 3D data (Google Solar, Google Earth, or a drone survey). 3D height data is what produces real shading; a flat 2D map carries none.
Place modules first. The analysis is most useful with modules across multiple roof sides.

Open the analysis

Place modules on the roof.
Click Shading at the bottom-left.
The menu splits into Sun path analysis and Sun heatmap.

Run the sun-path analysis

Choose a date and time (for example, 28 April, 12:00).
Turn on Show shadows.
Click play. The sun moves across the day, and you see when chimneys or trees shade which modules.
Change the date (April versus August) to check the seasonal sun position.

Apply the shading loss to the simulation

At the bottom of the Sun heatmap, Reonic shows the total shading loss for the layout (for example, 7.72%). Click Apply to transfer that value into the yield simulation so the economics reflect the real shading.

Things to know

For heavily shaded surfaces, consider flagging an optimizer or dropping individual module positions. You make those changes in string planning.
The sun-path view answers when and where the shade falls, and the heatmap answers which panels lose how much. Use them together. For the per-panel score and its colour bands, see the Heatmap page.

Need help?

Step-by-step questions about this flow → contact your Reonic account manager.
Feature requests / something missing → send a note to your account manager.
Bug reports → include a screenshot and the URL where it happened in your support email.

Last updated on August 4, 2026