Agnes Bridel

Here's a screenshot:

You should be able to change the altitude in the "Conversion of custom (sub-)hourly weather data files" window. After selecting your source file, you can click on "New" to select your site, and here you have the possibility to modify the altitude, which then will be taken into account in the simulation. Best,

It is currently not possible to import P90 data from SolarAnywhere through "Known format". This will be made possible in the upcoming version 8. In the meantime, you have the possiblity to import the data through "Databases > Custom file". For more information on importing custom files, please refer to the help page" Meteo Database > Import meteo data > Custom meteo file > Conversion protocol". Best,

Hi, Could you please describe how were the files imported? The SIT file seems to be correctly imported but not the MET file. this might be due to a step that is missed during importation? A quick verification will be to see if the MET file exists in the "Meteo" folder in your workspace. Best,

The most straightforward is to prepare your excel file in the PVsyst standard format for hourly meteo data. You can then import the file directly through "Databases > Known format" and select the PVsyst standard format from the dropdown menu. For more information on the format, please refer to the help page: https://www.pvsyst.com/help/index.html?meteo_pvsyst_standard_format.htm Otherwise, you also have the possibility to import your data through "Databases > Custom file". You will have to define the conversion protocol (MEF file) so that PVsyst can convert it to a MET file for the simulation. A step by step explanation on the custom file import can be found on the help page https://www.pvsyst.com/help/index.html?meteo_convdialog.htm Best,

At the moment, there is no specific snow model in PVsyst. The recommended way to account for snow coverage, is to use the monthly soiling losses. You need to estimate these monthly values outside PVsyst, either by simply using weather data on snow coverage, or by using some more sophisticated snow coverage modeling. This will then be considered as an irradiance loss. Best,

Few corrections or improvement have been implemented since version 7.4.4 and it is difficult to give an explanation on the discrepancy without more details. In general, there were no changes made in the transposition algorithm, but this could be related to some improvements made in terms of azimuth and tilt definition for tracker axes. please feel free to share your project at support@pvsyst.com so that we can take a closer look. Best,

Hi Allison, Thank you for bringing this issue to our attention. We are aware of the inconvenience and are actively collaborating with the SolarAnywhere team to implement a solution as quickly as possible. The current workaround is to download the data in CSV format and manually import it into PVsyst by navigating to "Databases > Custom file" and selecting the appropriate wind speed column for import. We appreciate your patience and understanding during this time.

PVsyst V8 is expected to be released at the end of 2024. If you would like to use data from Meteonorm 8.2, you have the possibility to download from the Meteonorm software and import it manually in PVsyst through "Databases > known format".

If you have Solcast data, you will have to select the Solcast option from the dropdown menu before importing your file. If the issue persists, please feel free to share your weather data at pvsyst@support.com so that we can take a closer look at the issue.

In PVsyst, Meteonorm versions are associated to PVsyst versions. For instance, Meteonorm 8.1 is integrated in PVsyst 7.4.7. Meteonorm 8.2 will be integrated In the upoming PVsyst version 8. It is possible to import Meteonorm weather data manually. You can do so through "Databases > Known format" and select the Meteonorm software option from the dropdown menu.

Hi Nuno, There were indeed a few comparisons done for different weather data sources. This comparison were done only between free sources, explaining why databases like Solargis, Solaranywhere and Solcast were not included. At PVsyst, we try to remain neutral by providing access to different databases without managing the data nor give preference to one or another. For more insights, you may also check out related forum posts to gain insights form other PVsyst users. Best,

Could you please verify that the parameters in "Detailed losses > Aging" are same in both cases and that the "Keeps calculated mismatch values" is activated? If that is already the case, please kindly send your project ("Project > Export the project") to support@pvsyst.comso that we can take a closer look.

The 25-year P75 concept is currently not yet implemented in PVyst and therefore cannot provide a 25 year list of P75 values automatically at the moment.

GlobEff is the effective irradiance in the PV module after taking into account optical losses such as far and near shadings, IAM and soiling losses. When visualizing the loss diagram in PVsyst, you can easily export the values by clicking the "Export" button. This allows you to paste the data into Excel or another spreadsheet application. The exported data provides a detailed breakdown of the losses and energy for each variable, allowing you to reverse engineer the calculations.

The bifacial system is available in the "System" part and is visible when you choose a bifacial module. You can define the bifacial model by clicking on "Bifacial system". The "GlobBak" variable should then appear in the simulation variables list in "Advanced Simulation > Output file".

Currently, it is not possible to integrate PVsyst with external software. However, the development team is working on PVsystCLI (Command Line Interface), which will enable automation and integration with other software tools. This product will be released alongside PVsyst version 8. For more information about PVsystCLI, please visit: Ongoing development of PVsyst 8 and PVsystCLI. Best,

Hi, The "GlobaBak" variable should appear if the bifacial system is activated. Could you please verify if the bifacial system is activated when defining your system?

Yes you're right!

Hi, GlobInc is the incident global irradiation in the collector plane on the front side. For parameters related to bifacial system, you could refer to the help page https://www.pvsyst.com/help/bifacial_results.htm for the definition of each variable. In general, there is GlobBak that represents the effective irradiance on the rear side. It includes direct and diffuse sky irradiance as well as the irradiance reflected from the ground. For all these three irradiance components, the shading and IAM losses are accounted for. You then have the possibility to export these variables in "Advanced simulation > Output File".

There are different possibilities to import measured data. The PVsyst standard format is the most straightforward way to import these data (see the help page "Meteo Database > Import meteo data > PVsyst standard format for hourly meteo data" for more information). Otherwise, you could also import measured data through "Databases > Custom Import". (see the help page "Meteo Database > Import meteo data > Import ASCII meteo files" for more information).

Could you please share the Vaisala weather data file to support@pvsyst.com so that we can take a closer look at this issue? Thank you in advance!

1. PVsyst takes into account two effects that contribute to the losses due to PV module aging: The average degradation of the modules expressed by the ‘average degradation factor’. This will give raise to the ‘global degradation factor’, which is the loss expected for a given year of operation. PVsyst will perform the simulation for the full year with a single degradation value calculated at the beginning of the simulation. Therefore this degradation should represent the average degradation for the entire year. The increasing mismatch caused by the different aging of the individual PV modules. The assumption in PVsyst is that the distributions of Impp and Vmpp will broaden with time. This broadening is described by the two factors ‘Imp RMS dispersion’ and ‘Vmp RMS dispersion’. To estimate how this will impact the overall mismatch losses of the strings, PVsyst will use a Monte Carlo approach and generate randomly many PV modules according to the distributions. It will then combine them to strings and calculate the mismatch losses. From this statistical ensemble it will get the estimate of the ‘Mismatch degradation factor’. 2. Running the module degradation factor post-simulation in Excel might overlook interactions between different system components and environmental conditions that PVsyst considers. 3. You have the possiblity to run 25 years simulation using “Aging tool” in “Advanced Simulation”.

While it is possible to load TMY files with PXX into PVsyst, provided that you already have these data in hand, unfortunately it is currently not possible to generate them directly in PVsyst... Best, Agnes

Hi Edwin, If you have 10 or more years of complete hourly weather datasets, it is possible to generate TMY weather data through "Databases > TMY generation". You will have to place the multi-year data in your workspace, PVsyst will then automatically detect these files and allow you to generate TMY files. More details can be found here: Meteo Database > TMY data generation (pvsyst.com) You can then run PXX simulations in "Energy management", Project design > P50 - P90 evaluations (pvsyst.com). Best, Agnes