Shading and shading losses calculations

[TurtlesOG]

Hello all,

I tried to search the solution for my question and although there are some topics about it, it is still not clear to me. When calculating the shadding losses, does PV*Sol only considers the losses for the shadded module or for the whole string (since it is also affected)?

What I really want to know is if PV*Sol will present a value of annual production taking into consideration the losses on the strings or only in the modules? Hope I made myself clear

Thanks in advance!

[developer_mh]

Hi TurtlesOG,

the shading (diffuse and direct) is calculated on module level, or more precisely on module substring level. The direct and diffuse shading affects the module IV characteristics, more on that here:

https://help.valentin-software.com/pvsol/en/calculation/pv-modules/shading-due-to-nearby-objects/

Then, all modules in a string are combining their IC characteristics to a string IV curve, and all strings are superposing them into a PV field IV characteristic. More on that here:

https://help.valentin-software.com/pvsol/en/calculation/pv-field/

So, in the end, for each substring of a module, each module, each string and each field (module area or combination of module areas), the IV characteristics are calculated for every time step. The MPP tracker of the PV inverter then sees the superposed IV characteristic and chooses the best working point on it, limited by its voltage, current and power limitations.

So, yes, of course, the electrical losses on the strings are taken into account, not only the individual losses the modules.

The overall losses per year due to shading are calculated by simulating the whole PV plant once completely without shadows, and then once again with the real shadow values. The difference of these two simulations is the "Yield reduction due to shading" that you can find in the simulation results:

 

Hope that helps, kind regards,

Martin