Leaderboard

When you put in value, you need to enter coma but not the dot.

Hello, I have a general technical question; is it ok to connect 2 strings with different modules number to one MPPT (18 and 19 for example when using the polystring feature in PV sol). I've read on some forums that there are losses due the voltage mismatch and the MPPT tracks the string with the lowest performance; but is it really a red line for PV designers or it's just not preferable and I can do it only when necessary? Thanks in advance Karam

Hi Burak, the 0,4 ct/kWh is the so called "Management Prämie" that shall compensate for the extra cost that a PV system owner has when he or she is opting for the "Direktvermarktung" In the numbers published by the "Bundesnetzagentur" those 0,4 ct/kWh are already included: https://www.bundesnetzagentur.de/SharedDocs/Downloads/DE/Sachgebiete/Energie/Unternehmen_Institutionen/ErneuerbareEnergien/ZahlenDatenInformationen/PV_Datenmeldungen/DegressionsVergSaetze_11-01_21.html They provide an Excel file that you can download, and in there there is a sheet called "Beispiele". Ther

Hi Ricardo, the active power will be capped. The output power clipping is based on the apparent power, say S_max. With cos φ = 1, the system will not produce reactive power, so active power equals apparent power, and the maximum power output is P_max = S_max. When the cos φ is smaller than 1, the maximum active power output will be reduced by this factor (while the maximum apparent output power remains the same), since P_max = S_max * cos φ. Hope that helps, kind regards, Martin

Dear Ricardo, unfortunately we don't have a detailed explanation of each item of the energy balance yet. But this is a good suggestion, we will put it on our request list for extending the help pages. The "Down-regulation on account of the max. AC Power/cos phi" takes place when the AC power of the PV system is higher than the maximum AC output of the inverter. In this case the inverter has to regulate the output power down to the maximum permissible power (by choosing another poit on the IV characteristics if the PV field on the DC side). The cos phi will reduce the maximum permissi

Hey there, There was similar question on this forum already. Hope it helps

Hi Sondre207, I must admit I missed your question. Sorry about that. Within the graphical allocation (2D) this is possible: Set installation type to Mounted - roof Uncheck Roof parallel and set a different module orientation Change the module inclination to 0° Change the row distance from 1m back to 0.005m to get rid of the default row distance In 3D you can achieve a similar effect by using module mounting: which results into this configuration: The problem is you cannot get rid of the mounting system as far as I'm concerned.. Y

While answering your question and after some tinkering with some bifacial modules: Here are three projects with the same location and inverters and reasonably comparable modules (I attached the projects too): 1. South orientation, non bifacial 2. South orientation (same as first), bifacial 3. East-west orientation (90° inclination), bifacial Where bifacial modules clearly shine is the third project, bifacial east-west 90 degree inclination. Naturally this is one of the most interesting of applications: Agricultural PV systems, perfect due

Main input parameter for this is "electricity tariff from grid" which one provides as input

For us, a fixed (or at least globally adjustable) colour scale for the shade frequency analysis would be very useful. So that e.g. 5% of shading has always the same colour for every roof in every project. As it is right now, 5% or even 10% of module shading might appear as a vibrant green, just because a part of the roof (maybe even with no modules) might be shaded very strongly. Not ideal at all. This, along with an option to export these pictures with one press of a button would be very useful to our workflow. As of right now we have to screengrab each and every roof. Edit: exmple pictu

@Vishnu: Thanks a lot for answering here! We really appreciate it a lot when you help out each other!

hey Alberto, I can think of only one reason for this. As you mentioned that you've used two difference modules, there is a chance that "Anti Reflection Coating" is different for the two modules. This is just my assumption, may be there is a better explanation the PV Sol team can provide. Also the "orientation and inclination of module surface" is different for the modules. Is the inclination different for both the cases?. If yes, this is also a reason for different reflection losses. Cheers..!!

Hi Kamal, these kind of bends occur when you have unequal number of modules in your strings. The curve section from 0V to the point where the bend occurs is where the two strings both deliver a current for the given voltage. After the bend, up to the open circuit voltage of the longer string, only the longer string (with 21 modules) can deliver current, the other string is not contributing anymore. Kind regards, Martin

Hi Martin, Thanks for the your helpful response! I used the feature to compare the IV curves as you mentioned. Do you (or any colleague in this forum) have/has an explanasion for the abnormality in the IV curve of MPPT 2 ? (please see the attached screenshots) Beste Grüße Karam

Hi Karam, no, I would not say that connecting strings with different module numbers is a red line in general. Why not try it out in PV*SOL directly? We calculate the losses due to string mismatch with great accuracy, so you can just see how much energy you loose in you PV system and see for yourself if you can accept these losses. You can also see the resulting IV characteristics of your parallel strings in the results page (under Simulation -> Diagram Editor -> Type of Diaram: Characteristics) Kind regards, Martin