Niels

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Hello, I can no longer import weather data from TMY 5.2, originally I encountered this in version 8.05, with some testing I had the issue in every version of pvsyst that I have installed including 8.0 and 7.4. I get the following error: https://i.gyazo.com/4683939abe4fb48af541b9166c66c62a.png

What is the source of the .ond files in the pvsyst database? are these made by pvsyst or the manufacturers? For a project I have the following 3 .OND files 2019 .OND name implies version 6.8 in pvsyst 2022 .OND by default in the pvsyst database 2023 .OND received directly from the manufacturer My problem is that the 2019 and 2023 are the exact same, both versions have the same values and ignore stuff such as maximum current mppt. Meanwhile the one in the pvsyst database as an incorrect current which when used would lead to weird capping losses. Are the .OND files in the database made by pvsyst themselves?

As the title states, does PVsyst factor in the shading thrown by windturbines when you create a windturbine within construction perspective? I have a project where there are windturbines right next to the solarpark so I expect significant shading in the afternoon both from the tower and the swinging of the blades. If PVsyst does not factor in the swinging of the blades, how would you suggest to factor in the shading loss?

Hello Andre, Thanks for the answer. While I agree that the first option is a fairly practical solution it sadly isnt usually applicable due to needing the exact same amount of modules and strings as in a customers contract. Next time this comes up I will try the second proposed solution. I do have 1 question with this, namely: doesnt using many different subarrays slow down the simulation speed? Quite often I find myself in the situation where a 40MW subsection of a project already takes multiple hours with only 2-3 subarrays, doing it in this manor would probably lead to many more subarrays.

Hello, I was going through my older simulated variants for a certain project and I couldnt open my report because i got an error for the transformer nominal power being far higher than the maximum output power of the inverter. After looking at the screen for the ohmic losses i saw the following: (first screenshot) For some reason the ohmic losses for the AC and trafo losses have disappeared? Its only for this specific pvsyst, at other pvsysts I still have my normal losses. see below (second screenshot) Please advise on how to continue, its unacceptable to loose results in such a way.

Hello, I currently have a problem with the power sharing function in pvsyst normally I use full inverters but due to a single string with less modules I need to use the multi-mppt feature Some information about my system 12 250kVA inverters, 144 mppt's in total 1 string of 24 modules, 610Wp 243 strings of 25 modules, 610Wp DCAC ratio of 1,24 PVsyst number 1 I used multi mppt feature but did not select power sharing. the 24 modules string has 1 mppt and the 25 modules 243 strings have 143 mppt's. This results in a pr 84,74% with a inverter loss over nominal inv power of 1,3%. The inverter loss is rather high for such a low DCAC ratio. PVsyst number 2 I used multi mppt feature but did did select the power sharing function. the 24 modules string has 1 mppt and the 25 modules 243 strings have 143 mppt's. This results in a pr 84,74% with a inverter loss over nominal inv power of 1,3%. Attached is an image of the settings of the power sharing. Despite enabling power sharing it did not result in a different outcome. PVsyst number 3 I used the multi mppt feature for the first string of 24 modules, for the strings of 25 modules i disabled the feature, instead of using 143mppt's i used 12 inverters. In theory i now use 1 mppt too much but I did it to test if disabling the multi mppt feature would result in more realistic results. The result from pvsyst 3 is a pr of 85,64% and a inverter loss over nominal inv power of 0,1%. As stated, with disabling the multi mppt feature the results of the pvsyst are far more inline with what we see in practise. If I missed something, please let me know. How to fix this issue? for this specific case I can work around it but there are more pvsysts where I need to use the mppt feature a lot.

I am currently working on a project where the client has requested that we use the global horizontal irradiation, horizontal diffuse irradiation and wind temperature from PVGIS CMSAF. The client gave the following instructions which I followed: Start with the default PVGIS import “PVGIS:TMY Sarah,Cosmo or NSDRB” Then go to PVGIS (version 5.1): https://re.jrc.ec.europa.eu/pvg_tools/en/#api_5.1 to download the following monthly data (PVGIS-CMSAF) for the location: (i) Global horizontal irradiation; (ii) Diffuse/global ratio (use this to manualy calculate the monthly diffuse horizontal irradiation); (iii) Temperature; Then overwrite the first three columns in PVGIS with this external data. Windvelocity and humidity remain unchanged. I modified the site by going into choose site > open the specific site and changed the data in monthly meteo. This gave me a glob hor of 1134,7 a diffhor of 601,1 and an T_Amb of 10,8 Afterwards I ran the Pvsyst however on the main results page I can see that the used data is from the original PVGIS TMY import namely: globhor 1139,7 diffhor 557,4 and T_Amb 10,5 and not the modified version. Please advice on what went wrong and how I can get Pvsyst to use the modified data.