Discretizing ground surfaces and variable albedos

[anomam]

Hello @renegacitua,

I'm creating a Github issue for the question you asked in #119 so that I can better keep track of things, and so that other people with similar questions may easily find it.

Hi, i'm starting to use pvfactors, is a really great tool, but i had a question. Is the program capable of discretizing the terrain? I mean, I know that it consider the "cut points" and the shadow and not shadow areas, but it can consider a certain zone where I can consider a bigger value of albedo? In other words, i want to quantify the impact of install a reflective surface on the front or under of the PV row, is this possible with pvfactors? What would you recommend me for this? I appreciate your help, regards!

[anomam]

Sorry for the delayed reply @renegacitua, I went a bit MIA for a couple of months because of travels and professional constraints but I'm back now! Unfortunately pvfactors doesn't currently allow to define ground surfaces and therefore discretizing them or allowing different albedo values. But I would greatly appreciate a PR if you have some ideas on how to implement that : )

[nicorie]

For this task I can recommend bifacial_radiance, though the learning curve is steeper than pvfactors. You can define the reflectors area using the makeCustomObject() function. The reflector's properties can be defined in the Ground.Rad file.

[renegacitua]

Sorry for the delayed reply @renegacitua, I went a bit MIA for a couple of months because of travels and professional constraints but I'm back now! Unfortunately pvfactors doesn't currently allow to define ground surfaces and therefore discretizing them or allowing different albedo values. But I would greatly appreciate a PR if you have some ideas on how to implement that : )

@anomam Thanks for your reply, a couple of months ago i was working with pvfactors, as you mention it wont allow the discretization of the terrain, so i start to work with bifacial_radiance.

But to what you mention, after using the library, I think that the program could implement, without so much work, the function of creating an extra surface(s) on the axis generated at y = 0 and therefor fix the value of the albedo to each particular surface. It would be similar to adding a shaded surface and calculating the view factor between the different surfaces.

In this way, a number of variables equal to the number of added surfaces would be added to the view factor resolution matrix.

[renegacitua]

For this task I can recommend bifacial_radiance, though the learning curve is steeper than pvfactors. You can define the reflectors area using the makeCustomObject() function. The reflector's properties can be defined in the Ground.Rad file.

@nicorie thanks for the reply. Yes i've been using bifacial_radiance since a while and obtaining some results for the reflectives surfaces. Anyway i haven't been able to import my own TMY file, the one that the software downloads based on the latitude and longitude.