I have a few questions concerning the way the ground reflection on the front side is considered in the loss diagram and in the calculation of the Performance Ratio:
The Performance Ratio is basically the resulting specific yield divided by the irradiation on the front side. Why does an increase of the irradiation due to the “Ground reflection on front side” change the PR? For systems with steep module tilt angles the difference in PR values would be significant. I have attached an example for a vertical Agri-PV system.
In the field, shouldn’t the “Ground reflection on front side” also be measured by an irradiation sensor? If yes, there would be a big difference in PR, when comparing a “real” PR with a PVsyst simulation.
At the moment, ground reflection is listed after soiling and IAM factor. Shouldn’t it be considered before, as these losses affect the reflected light as well?
For the near shading irradiance losses: are they considered for the calculation of the ground reflection? In the mentioned example, where the ground reflection is over 13%, the influence of these losses on the reflected light would change the results significantly.
If find it also problematic that the results for such a system depends on the bifacial simulation and the simulation results are inconsistent with a monofacial simulation. If one would want to simulate for example a monofacial vertical system (e.g. façade), the results would differ. Do you think that in the foreseeable future it will be possible to have a better consistency in PVsyst regarding monofacial/bifacial simulation?
Thank you very much for your help!
