André Mermoud

This depends on your system layout, especially on the shadings. If you have a system without regular shadings (not a "row" or "sheds" system), you can use "Databases > Tools > Transposition factor". If you have a system in sheds, the shading losses deeply modifiy the optimum. In the "Orientation" dialog, you can see "Unlimited sheds > Show Optimization", and here presss F1 for getting an explanation.

In PVsyst the time labels always represent the beginning of the interval. 11H represents the average of the 11h to 12h values.

I don't know. The Shading objects should be defined as such in the Helios3D program. It is a specific definition in their output file. Now there may be a "youth" problem with this import. Please send your Helios3D file (*.h2p) to support@pvsyst.com.

If there is a red warning on the blue top right panel, the Model page is indeed not available. Now since version 6.39, there is indeed the possibility that the Rserie or Rshunt definitions produce a read warning, and this will hide the panel where you are defining these quantities. This is indeed a bug to be corrected. However you can: - either define these parameters using the "Show optimization" dialog (bottom left button). - or start from an existing module and modify its parameters.

When watching the report in the dialog of the "Report" button, ypou have an option "Units".

You have not defined the Filename for each hourly files (*.CSV).

PVsyst doesn't treat this behavior in the present time. I have not seen much inverters with these characteristics up to now. During the simulation, PVsyst clips the voltage at the limit value, and therefore displaces the operating point on the I/V curve, leading to losses with respect to the Pmpp array possibility. So that the efficiency limiting is related to the PV module's properties rather than a special inverter behavior. The results should not be very different. For the lower voltage, the "Minimum voltage for PNom" represents indeed an input current limit. The limit current is indeed Pnom / VMinPnom. When the array MPP voltage is below this limit, the inverter works at this fixed input current on the P/V curve.

The formula is mentioned in the Help "Project design > Array and system Losses > Array thermal losses".

The times when this arises are very close to sunrise or sunset. For these hours including the sunrise (or sunset), PVsyst considers the time between sunrise and the end of the hour, and computes the solar geometry at the middle of this interval. The Direct normal is computed on the basis of the GlobHor, DiffHor and divided by the sin(sun height). The cut on Sun height is rather low (I dont remember the value). But there is a cut of 10 W/m2 on the GlobInc value for the rest of the simulation. Now for your tracking situation (probably with backtracking), the plane is almost horizontal (1-2 degrees) so that the GlobInc value is very low at sunrise. On the other hand, there is a cut on the incidence angle (>88° doesn't make much sense due to the IAM loss). This explains the null values of BeamInc.

This is indeed a very difficult task. Our IT specialist has already passed some hundreds of hours on this development. Some parts of the calculation are now "threadable" without error. However there are still ununderstood bottlenecks and we don't gain any significant time.

This tool "Long term Financial Balance" has indeed a parameter "Annual Production reduction" (expressed in %/year). Here, if you click the button "Graphs" - "Table", you will see a column for the sold energy yearly revenue. However the simulation results are for the first year (except if you take the ageing into account in the "Module Quality Loss").

The database is updated with each new version, according to the requests of the manufacturers.

The ground object is a new tool, and we did not yet have time for developing all related features, like positioning trackers on it. This will be done for a next version. You can always define trackers at different altitudes. However with such a system the backtracking strategy is not well defined. PVsyst cannot calculate it.

Please have a look on the help : "Meteorological data > Hourly Meteorological data > Hourly meteo data quality check" and " ... > Time shift" The dates are normally read on the file (in a specified format - pay attention to the formatting: MM/DD/YY in the US, DD/MM/YY almost everywhere else). But if you have a TMY file (with diferent periods), you cannot read these dates and you have to choose "Generic year".

If you consider the thermal loss as your decision, and not the result of the simulation, you can of course put the parameter you want for getting this result.

Some SMA inverters have indeed a very large Power factor range. SMA claims that you can even specify Cos(Phi) = 0 (means that the inverter produces reactive energy during the night) but this doesn't make sense for the results of the diurnal simulation. This is the reason why we limited the Cos(Phi) to +/- 0.1. For the parameters in the PVsyst database, they have been specified by SMA people. Please ask them. However you are right: suppose you have a cos(Phi) of 0.1, the apparent power at Pnom = 25 kW (effective) would be 250 kVA, which means a quite irrealistic current ! The PNom limitation is usually corresponding to an output current limitattion, and should indeed be expressed in kVA.

In the Database management, you have a tool for exporting the data as EXCEL lines, for use in the document Components.XLS. Here you can export several components at a time. You will find this file in c:\Program files (x86)\PVsyst6.x.x\DataRO\PVsyst6_Data\UserData\ I don't know any other component database which would provide sufficient information (parameters) for use in PVsyst.

This is not possible directly as standard output of PVsyst. You can manage for getting the relevant values using the Monthly tables (you can get data for any chosen variable of PVsyst). But this will not give the Loss values in percent as on the array loss diagram: you have to calculate them in EXCEL.

Thank you for this information. I have corrected for the next version 6.39.

Sorry, this is not possible in PVsyst: you can only define different orientations for full strings. This is suited for "normal" strings, where current mismatch may be catastrophic. Although such a configuration could be used with the SolarEdge optimizers, it is not implemented in PVsyst in the present time.

The values of the parameters (Rserie and Rshunt) in the database have been set by Sunpower people. Now the SPR-X21-345 module has a very low Rserie = 0.39 ohm, leading to bad low-light performances (relative efficiency -1.1% at 600 W/m2, and -5.4% at 200 W/m2). When the SPR-E20-327 has a higher Rserie = 0.54 ohm, leading to better low-light performances (relative efficiency -0.3% at 600 W/m2, and -3.1% at 200 W/m2). Therefore it is quite normal that the Irradiance losses of the X21 module are higher than the E20 module. By the way, we can observe that these low-light performances (as stated by Sunpower for the PVsyst database) are much lower than the performances of all equivalent modern modules. The new standard of PVsyst for the default value of Rserie is to set -3% at 200 W/m2, and this is a cautious estimation. NB: The temperature coefficient stated for the X21 (-0.30%/°C) is significantly lower than for the E20 (-0.38%/°C). This compensates a part of the Irradiance loss effect.

This depends of course on the geometrical positioning of your installation. You don't tell anything about this.

I don't understand your statement. You don't mention that the irradiance level changes. For the "Mixed orientation" calculation, the I/V curves of both orientations are mixed at each simulation step, and the resultant is used for the Pmpp determination. Mixing strings of different orientations usually doesn't produce much mismatch losses.

Sorry, the Batch mode only concerns simulations, it is not developed for the import of meteo files from other sources.

I don't understand the question. The option "Import ASCII Meteo file" is a button in the "Database" part. You can open it and press F1 for getting the procedure.