André Mermoud

Your parameter definitions are correct. The inactive bands are the eventual mechanical parts, which extend over the width of the modules and provide shadings on the next tracker. By the way when defining a tracking system, you have to define a 3D shadings scene (even with backtracking as you have shading losses on the diffuse part). And here you will visualize the signification of these parameters.

You cannot keep your license when you quit your company. The PVsyst licenses are attributed to a given company, not a person.

Please read first our most recent post on this topic: https://forum.pvsyst.com/viewtopic.php?f=17&t=4125 For creating an "Interactive map", PVsyst needs to get an access to Internet for using the web service "OpenStreetMap". In some companies the access to internet from applications is secured through a proxy or a Firewall. Our proxy settings implementation is actually limited to some common proxies. If your proxy uses a proprietary way for authentication, then it will not work, and we cannot do anything. What we usually suggest in this case, is to configure your environment (proxy/firewall) to allow PVsyst to go over internet. PVsyst actually uses the following accesses : - Any PVsyst base host URLs : https://www.pvsyst.com - License management (activation, transfer, sync) : https://secure.pvsyst.com/activationCenter/ - Meteo definition via Interactive Map : https://www.openstreetmap.org - Locality and timezone : http://api.geonames.org, http://ba-ws.geonames.net and http://ba-ws2.geonames.net - PVGIS meteo and horizon import: http://re.jrc.ec.europa.eu/ - NREL NSRDB meteo import: https://developer.nrel.gov/ - Currency exchange rate: https://data.fixer.io/ - PVsyst's software update : http://download.pvsyst.com/. However the "Interactive map" is not necessary for creating a new site: you can simply choose the page "Geographical coordinates", and explicitely define your site by its GPS coordinates (Latitude, Longitude, Altitude, Time Zone), which you can get from other sources. The "Interactive map" is only a tool for simplifying your life.

First, please have a look on the FAQ How is calculated the PR ?. Your expression is the one used in PVsyst, except that the Effic (NOCT) is indeed the Effic at STC. In fact, the definition in PVsyst is PR = E_Grid / (GlobInc * Pnom) where Pnom is normally equal to Effic(STC) * module area. Now as it is normalized to GlobInc, the PR is an indicator of the running quality of your system, independently of the orientation and the climate. You have a south and a north orientation (with probably very little tilt, and a very low positive latitude - near to the equator). The southern part is more exposed (higher incident irradiance): its temperature will be slightly higher than the northern orientation. Therefore its temperature losses will be slightly higher, i.e. the PR will be slightly lower.

This is treated in the "Module Layout" electrical shadings part. After defining the Module Layout, you can perform a pseudo-simulation and observe the behavior of the I/V curves under shadings along the day. You are right, the MPP voltage will drop, in about the same ratio as the number of submodules shaded. This is the reason why with sheds arrangement, the "beam" production is completely lost as soon as the first bottom cell is shaded (see our FAQ "How to evaluate the effect of by-pass diodes in shaded arrays"). And indeed the MPP voltage often drops below the VmppMin of the inverter. Up to the version 6.32: the voltage was clipped to the VmppMin, Since version 6.33: if the Vmpp is under the voltage limit, PVsyst will search for the secondary maximum (which corresponds to the MPP for the diffuse). In the yearly simulation, both options give very close results. However the Module layout electrical shadings are not treated in the version 5.

In the 3D editor: When defining a "PV plane in sheds", you have the opportunity of specifying "shed-to-shed slope". If you have different shading objects (or planes), you can always specify their altitude. Now since the version 6.33, you can define a terrain ("Ground object"), and position your fields ("Tables") automatically according to the terrain altitude. NB: You cannot specify a slope with the simplified orientation choice "Unlimited sheds".

You cannot delete components from PVsyst. You have to use your Windows File explorer for suppressing manualy the concerned files in your data in \MyDocuments\PVsyst6_Data\Components\Inverters\

This is due to shading effects on the diffuse. Please see the FAQ How is calculated the shading loss on diffuse with tracking systems?

As for the initial degradation of amorphous modules, the initial state without LID is neglected for the simulation. The simulation results are usually meant as a "normal year" yield, and often assumed as a result valid over several years (by sometimes applying an annual degradation on the results for the next years). This would not make sense to take a transitory effect into account in the general simulation evaluation. By the way the LID loss -and its evolution/durability - is never well known (may depend on the crystal quality, the production batch, etc). The little gain we could observe by treating this initial degradation is probably completely negligible, far below the uncertainties of the rest of the simulation. The important thing is to determine the absolute value of the LID loss (by respect to the specified STC performance), as it will affect the yield during the whole life of the power plant.

This is corrected in the version 6.33. However the option "Create from" is only useful for copying a calculation version from another project. In a given project, you can always open an existing calculation version, modify it and save it as a new version. For using a calculation version from another project, you can always rename it (or create a copy) with your target project name (using the Windows file manager).

No sorry, this is not possible with tilted tracking axis. However if you have an array of this kind, the mutual shading effects and all other performances will be the same as for a "normal axis" system.

Sorry, this is not possible in PVsyst. This would be very difficult to manage reflexions in a general way, as these are highly dependent on the geometry, the incidence irradiance and the surface's reflexion properties. By the way please remember that in a string of modules, the current of the worst cell drives the current of the whole string. Therefore if you don't have a perfect uniformity on at least one string area, you won't gain anything.

When you are in the shading 3D editor, in the main menu you have the option "Files" > "Save scene view" > "Keep this view for the report" You can manage your desired view in the editor (including shaded situation), and then use this option for the next issue of the report.

This reference of the AC loss with respect to Pmpp(STC) is a default value, it is a first guess proposed by the software for a quick estimation of a reasonable value. The real relevant value is based on the Rwiring value, that you should ideally calculate for your actual wiring installation. The resulting ohmic wiring loss is indeed expressed as a percentage of the Energy remaining at this point of the simulation. You can have a look on our FAQ "How to determine the Wiring loss Parameter", and also How to determine the parameters for external transfo loss ?.

Not in the present time. We will try to do that for a next version.

The simulation of PVsyst works on an hourly basis: one calculation for each hour, according to the meteo data for this hour (Global and diffuse irradiances, temperature). Now when meteo data are only available as Monthly values, PVsyst has to generate a synthetic hourly data file (random distribution) for working. See our FAQ What are Synthetic Hourly Data ?

Indeed, I don't know any systematic and significant differences of PR between different technologies in "usual" climates. Sometimes it may be more, sometimes less. Only the simulation can give an answer in a given climate, and you have an estimation of the respective irradiance and temperature losses. Moreover, the comparison results are not necessarily reliable as the module's performance parameters may be defined in different ways (Manufacturer-defined or default parameters for Rserie and Rshunt, etc). We don't have a detailed measurement report for each module (especially for low-light performance, i.e. Rserie determination). As you point out, it is possible to have less thermal losses with thin film technologies with lower muPmpp coefficients in very hot climates, but 8 to 10% seem a very high discrepancy.

When defining the batch mode, you should tick "Create Hourly File". If you do that, when exiting the batch mode dialog, the dialog for the definition of Hourly files appears after the message : "You have to define the contents of your hourly file". However you can also define the output CSV file by the button "Output file". On the batch parameters defintions sheet, you will have to specify a filename for each hourly file you want to create.

There are some few references for particular cases. But I don't know any general study nor methodology for the estimation of the soiling factor in any situation.

Many questions. The shading losses in PVsyst are of several kinds: - Loss on the beam component: the shading factor is the ratio of the shaded area to the total sensitive area. This may be pre-calculated in a table (as function of the sun's orientation) for a quick use by interpolation during the simulation. This may also be calculated at each simulation step (slower process). - Loss on the diffuse component: this is based on the hypothesis of an isotropic diffuse, and results from an integral of the shading factor for rays comming from all directions "seen" by the collector plane (orange slice of the heavens between collector plane and horizontal). This doesn't depend on the sun's position, and is therefore constant over the year. - Loss on the albedo component: same idea than for the diffuse: the integral is performed on the "orange slice" between the horizontal plane and the prolongation of the plane undergroud. The factor is shaded for parts below obstacles on the ground. There are also the shading factor "according to module strings" and "according to module layout" for the electrical mismatch effect, but this is another question. Now when you have a completely covered day (i.e. without any beam contribution), the shading loss in indeed determined according to the constant loss factor on the diffuse, what you observe in your results. In the results, you can get the 3 contributions (in hourly or monthly values): ShdBLss, ShdDLss, ShdALss, ie. shading losses on beam, Diffuse and Albedo respectively. And the corresponding shading factors (0 = full shading, 1 = no shading).

There is no way for doing this directly in PVsyst. However you can perform a simulation with the tracking option, and another one with a fixed plane at the "blocked" position. For each simulation you can produce an hourly file. In EXCEL, you can mix your 2 runs by choosing some hours with tracking and some hours with fixed plane.

I don't see what you mean. The images correspond indeed to the parameters specified. Perhaps you don't interpret them correctly.

The specificities are transmitted to the EXCEL database file, but only 4 lines (columns in EXCEL) are recorded. Sorry, we don't intend to offer possibilities of extending the "free" definitions of components in the present time.

I don't see the difference you do between the feed-in tariff and the export tariff. However this tool doesn't offer very detailed economic calculations. There are so many ways of doing business plans and getting economic indexes. We intend to improve it in the next months.

In the calculation version définitions, please use the button "Miscelleanous tools". Here you have an option for specifying a limit for the Grid power injection.