Sebastian.stan

Hi Andre, I'm working on a project with a grid limitation of 100 MW at the injection point. The hourly .csv file shows the E_Grid is actually limited as 99.86 MW. Any idea why the discrepancy? The same issue with any other grid limitation values, checking or unchecking the separate loss box. Also, a similar issue with applying the limitation at the inverter level, except it is seen at EOutInv Best Regards, Sebastian

I have created a parallelepipede elementary shading objects and I am trying to give a tilt angle of -10 degrees (to point "downwards"). I get repeated messages that the value should be between 0 to 90, although the object actually changes the tilt to -10 as instructed. The warning messages were not appearing in the previous versions.

Hi Andre, In "albedo - settings" -> "other limitations": What is the difference between: - "Discriminating orient. difference between shading planes" - "Maximum orient. difference for defining average (spread) orientation". The second one does not seem to do anything to my Helios3D model. Am I missing something? The help section points out to 3 completely different items: - Max orientation between shading plane - Heterogeneous fields: maximum angle difference for shadings - Helios3D: Maximum plane orientation differences Thank you, Sebastian

Hi Andre, I was digging deeper and it seems that the same issue occurred before for version 6.26 http://forum.pvsyst.com/viewtopic.php?f=4&t=1788 As you mentioned in that post the issue was with transferring data from a normal variant (.VC) to a comparison one (.CM). I know that in version 6.38 this worked easily by: - going to the "measured data analysis" - choosing a VC variant from "create from" button - selecting the measured data .DAM file - running the simulation. However, since updating to version 6.41 (same for 6.41 and 6.43) we cannot select the .VC variant any more and have to build the .CM one from scratch. Am I missing some steps in the process? Best Regards, Sebastian

Hi Andre, I updated my version to 6.4.1 and it seems that there is a problem with the "measured data analysis" tool: After creating a .DAM file from "import ascii hourly file" tool, I am trying to run a simulation using one of my previous variants together with this .DAM file for analysing the expected yield. If I select the .DAM file at the "meas. data" drop down menu, and I build a system variant myself from scratch, it works fine. But if I try to import a variant with the "create from" menu, the software just ignores the .DAM file and runs the simulation with the original (meteonorm) meteo file. With the 6.3.8 version it was working (and still is if I use the parallel install) Has the procedure for this changed or is it an issue with the new version? Best Regards, Sebastian

Hi, What I failed to mention was that my monthly soiling losses are significantly larger in winter than in summer. Looking closer at the irradiance for the east facing project, it seems that the values are quite a bit lower in the winter compared with the south facing project. This means that the soiling losses in the winter don't affect that much the overall project losses as they would in the case of south facing. The values make sense now. Hope my reasoning is right. Best Regards, Sebastian

Hi Andre, I'm wondering how is the overall soiling loss factor calculated from the monthly soiling values. I was surprised to see that for one project with unlimited sheds facing south the soiling loss factor is shown as 8.5% and for facing east (-90 azimuth) the soiling loss becomes 7.4%. This is for the same project inputs (and same monthly soiling values), the only value I changed was the azimuth. This tells me that the azimuth is somehow part of the equation for soiling, but I don't see why or how. Could you shed some light on this? Thanks, Sebastian

Hi Andre, Thanks very much for your answer. Best Regards, Sebastian

Hi, I'm trying to use the Measured data analysis tool for comparing the actual production of a PV system to the expected one from the simulation. The comparison is based on five days worth of data (collected by the SCADA system) where the irradiance is at minimum 500 W/m2 for 3 hours. In order to import this data in PVsyst I use the "Import ASCII Hourly file" tool and my file includes the date, hour, measured irradiance on plane and ambient temperature for those 5 days. If I try to import this file I get the error message "This part is suited for comparing measured output data recorded on an existing PV system to simulated results". Fair enough, I add the measured energy injected into grid (E_grid) data to the file and it is imported correctly into PVsyst. Then I move on to the "measured data analysis tool", I use an as-built simulation variant and the measured data I just imported to get a simulation. Now, my understanding is that this simulation will show me the expected energy injected into grid (E_grid) using the meteo data I just imported. But does it do any actual comparison with the measured energy injected into grid I have added to the file? If not, what was the purpose of including the energy injected into grid in the file at the beginning? Please let me know if my understanding is correct and I am using the tools as they are designed? Best Regards, Sebastian