What is the Ground Cover Ratio calculation?

[AKSolar]

It seems that PVsyst is calculating the GCR using the the actual panel width, regardless of tilt angle. Wouldn't it make more sense to use the width from a top-down perspective, taking into account that a higher tilt angle shortens this width?

Additionally, the Optimization tool used the term "Active Area Ratio" but this is never defined. Is this the same as GCR?

[André Mermoud]

The "Active area" is the PV modules area. In PVsyst, it is the area of one module (LengthxWidth) times the number of modules.

The "Ground area" is the area occupied by the PV array (not strictly well defined).

The usual definition of the GCR (Ground Coverage Ratio) is the ratio of the Active area to the Ground area.