developer_mh

Hi Karam, no, I would not say that connecting strings with different module numbers is a red line in general. Why not try it out in PV*SOL directly? We calculate the losses due to string mismatch with great accuracy, so you can just see how much energy you loose in you PV system and see for yourself if you can accept these losses. You can also see the resulting IV characteristics of your parallel strings in the results page (under Simulation -> Diagram Editor -> Type of Diaram: Characteristics) Kind regards, Martin

Hi Fritz, the Module-independent shading is reducing the global radiation on the module, sure, but it is not part of the PR calculation. It just leads to a reduction of the radiation, like it would if you take climate data for another location with less solar radiation, for instance. In contrast, the losses due to the reflection on the module surface are both reducing the global radiation that is available for electrical conversion _and_ it is accounted for in the PR calculation. Yes. Or more precisely, yes, given that the modules are connected to the same MPP tracker and are part of the same module area. The lowest diffuse shading value of the modules connected to one MPP tracker is taken as module-independent shading factor. No, the shadow calculations work for all kinds of shading objects in the same manner. Concerning the UA, you are referring to this help page, I guess: https://help.valentin-software.com/pvsol/2019/calculation/pv-modules/module-temperature/ The heat loss rate is part of the PV module temperature calculation and is therefore also part of the PR calculation. To put it the other way round: All the losses you see in the energy balance, between (Global Radiation at the Module + Reflection on the Module Interface), and the PV energy (AC) minus standby use, is integrated in the PR calculation. Hope that helps, kind regards, Martin

Hi Vishnu, the feed-in management or maximum power clipping or "Einspeisemanagement" in German can be edited on the page "System Type, Climate and Grid". https://help.valentin-software.com/pvsol/2019/pages/system-type-climate-and-grid/#ac-grid https://help.valentin-software.com/pvsol/2019/navigationsseiten/anlagenartklimaundnetz/#ac-netz There you can enter the power clipping in % of the installed DC power, and you can choose if the inverters are limiting the power or if it can be done at the feed-in point. In case of the latter, possbile self consumption or battery charging can take place before limiting the PV production. The results (the actual losses due to clipping are shown on the results page. DEpending on what type of clipping you choose, the values are presented differently. If you don't have electrical appliances (consumers) in your system, the losses can be found in the energy balance of the PV system: If you have electrical appliances and you choose power clipping at the feed-in point, the losses can be found on the overview pages: In the diagrams: In the table views: And of course in the energy flow graph: And a side note: If you analyse clipping behaviour and you want to know the energy losses, we strongly recommend using one-minute resolution for the simulation. Hope that helps, kind regards, Martin

Hi ZhAta, it is true that formally the MPP voltage is too low and the current is too high if you connect 6 x 22 JA Solar JAP6(K)-60-270/4BB modules to a Fronius Eco 27.0-3-S. With the check temperatues of 15°C (U_Mpp_Max), 70°C (U_MPP_Min) and -10°C (U_OC) there is no way around it. You could have 5 x 24 modules, then the current limit isn't hit and the MPP voltage limits are fine, but still the Open Circuit voltage will be exceeded. But the question is, how much energy do you loose if you connect your system like this? I simulated your system with one-minute resolution (to get a realistic estimation of the clipping losses) and it looks ok: The down-regulation on account of the MPP voltage is relatively high, 1287 kWh, but it is still only -0,76% of you energy that you loose. It is then up to you, the planner, to decide if you want to accept these losses. If you are bound to these specific modules and this inverter, I guess you have to You can try different configurations, simulate them and see what you prefer. Hope that helps, kind regards, Martin

Hallo Richard, aus dem Fehlerbericht ist herauszulesen, dass es zu Problemen beim Laden von den Tarifen kommt. Die Version, die ihr benutzt ist leider ziemlich alt, so dass wir diesen Fehler höchstwahrscheinlich in der Zwischenzeit schon behoben haben. Daher lohnt es sich immer, mit der aktuellsten Version zu arbeiten. Es sind auch viele, viele neue Features darin und ihr könnt sie 30 Tage kostenlos testen: https://www.valentin-software.com/produkte/photovoltaik/57/pvsol-premium Beste Grüße, Martin

Hi Ricardo, I mean you could still use the configuration as in your version 2. The maximum current is only exceeded by 0.54 A, I guess that the energy losses due to current clipping will not be too high. I just simulated it with one-minute values for Berlin, and the current clipping (down-regulation) is really insignificant. Kind regards, Martin

ah, you were faster. So the database entry is wrong. I will inform our database team.

Hi Ricardo, how it would be done in the real world is a very good question. I guess you should ask the Huawei people I quickly scanned the user and installation manual for the SUN2000-20 KTL but I did not find any settings that would tell the inverter how to handle the MPP trackers and DC inputs. The ability to operate the MPP trackers together is something that the manufacturers enter into our database. So perhaps it would be best to ask the technical support of Huawei. support@huawei.com Kind regards, Martin

Hi Fritz, the performance ratio is calculated as the ratio of the total energy yield to the theoretically possible energy yield. That is, we take the energy output in kWh, E_total, and divide it by G * A * eta, where G is the irradiation on the module surface, A is the surface area of the plant and eta is the STC efficiency of the modules. So, to answer your question, what exactly is G, the irradiation on the module surface? I will copy an energy balance here in order to illustrate the different shading and reflection items: We calculate the reflection onto the module surface as the "Global Radiation at the Module" minus the "Reflection on the Module Interface", since this is influenced by the module properties. So the PR in this case would be PR = 14194,57 kWh / ((1122,50 +27,61) kWh/m² * 83,83 m² * 0,181) = 0,8134, or 81,3% We have two shading items in the energy balance: Module-independent shading in the meteo block, and module-specific partial shading in the PV field block. The first is not accounted in the calculation of the PR, the second is. The module-independent shading is the diffuse shading that is affecting all modules equally. The diffuse shading is evoked by obstacles (near or far) that are blocking the view to the sky hemisphere and is applied to the diffuse fraction of the solar irradiation only. We calculate the diffuse shading factor for every module and determine the maximal value that applies to all modules. In real world situations this minimal factor will most likely only cover the horizon or shading by far objects. When you have regular rows of modules then the diffuse shading factor for the inner modules will be higher due to the shading by the row in front, but the first row will have a lower value for the diffuse shading, so this value will be selected for all modules. All the rest of the diffuse shading and the direct shading is considered in the module-specific partial shading. Does this answer your question? You can also take a look here, there are some more details about irradiation and shading and so on: https://help.valentin-software.com/pvsol/2019/calculation/ Kind regards, Martin

Hi Jan, that is right, the modules need to have a distance from the ground in order to receive irradiation onto the rear side. Try to use mounted systems in 3D, either on the ground or on roofs, then there will be bifacial gains. Kind regards, Martin

Hi simonsolar. right now it is not possible to enter non linear temperature coefficients or IAM. We are aware of the fact that there is a need for this and we have it on our list, but right now we can't name a possible release date for these features. Kind regards, Martin

Hi James, glad that you like it. And thank you for your kind words Kind regards, Martin

Hi Jtebuck, there are various kinds of clipping mechanisms in PV*SOL. 1) There are inverter clippings due to voltage, current or power limitations that take place directly in the inverter. You can see these effects in the results in the energy balance: 2) Then there are maximum power clippings that you can edit on the page "System Type, Climate and Grid" in the AC mains section: I guess this option would be the best to suite your needs. The clipping threshold is set in % of the PV power installed on the DC side, so you would have to calculate the corresponding percentage beforehand. Let me know if this is what you need. Kind regards, Martin

Hi Raphael, yes, it is sufficient to install just the latest version. All installers of PV*SOL comprise the whole functionality. Kind regards, Martin

Hi Marta, yes, this message is shown when the total upload size exceeds 10 MB (which was the limit for all users). I raised it to 20 MB now so you can retry and upload the other screenshots. Kind regards and have a nice weekend, Martin

Hallo, die einzige Möglichkeit, die ich da sehe, wäre genügend Module in die Strings zu packen, also mindestens 13, die ausreichend bestrahlt werden. In diesem Fall würde das aber nicht gehen. Eine andere Lösung wäre, einen anderen Wechselrichter mit einer niedrigeren MPP-Spannung zu verwenden. Der SE6000H z.B. arbeitet auf 380V, das wäre in diesem Fall schon sehr viel passender: Beste Grüße, Martin

Hi Marta, I am not sure if I can reconstruct your problem correctly. Could you describe step by step what you do (click) after opening PV*SOL? This would be helpful. Ideally you could provide a screenshot of each step. Which version do you use? Do you use climate data that you generated yourself? Kind regards, Martin

Hi Gustavo, you would need to fill up the data series for 365 days. If you have a 15 min resolution, you need 35040 values for one year. Since you have only 337 days of measurement, PV*SOL 'complains' that the number of records is wrong. The solution is to provide a full year of data, then it works. Kind regards, Martin

Hi Vishnu, thank you for your question. We calculate the Return on Assets (german: Gesamtkapitalrendite) with the internal rate of return (interner Zinsfuß). In the old help files, this information was provided in the glossary: http://3d-help.valentin-software.com/pvsol/en/#t=html%2Fen%2FBegriffe.htm&rhsearch=internal rate of return&rhsyns= &rhhlterm=internal rate of return We will add this information to the new help files. Thank you for pointing us to the missing info. Here is more on the method to calculate the internal rate of return: https://en.wikipedia.org/wiki/Internal_rate_of_return Hope that helps, kind regards, Martin

Hallo GeromeK, die Klimadaten in PV*SOL kommen von MeteoNorm, einem speziell auf Klimadaten spezialisierten Produkt. (https://meteonorm.com/) Die Daten für Deutschland beruhen auf den langjährigen Zeitreihen des Deutschen Wetterdienstes. Sobald der DWD seine Testreferenz-Zeiträume aktualisiert, landen diese Daten also zunächst in Meteonorm und dann mit dem nächsten Aktualisierung der Schnittstelle bei uns. Es ist also nicht so einfach möglich, einen aktuelleren Zeitraum zu wählen. Wenn die Klimadaten aktualisiert werden, informieren wir darüber natürlich in den Release Notes. Hier noch etwas ausführlicher zu den Test-Referenzjahren: https://help.valentin-software.com/pvsol/2019/berechnungsgrundlagen/einstrahlung/klimadaten/ Beste Grüße, Martin

Hallo GeromeK, vielen Dank für das Projekt. Für die anderen Leser fasse ich mal die Anlage-Konfiguration zusammen: In diesem Fall sind 14 Module mit SolarEdge P370 Powert-Optimizern auf einer Dachfläche (Nord-Ost) in Reihe geschaltet mit 10 Modulen auf der gegenüberliegenden Dachfläche (Süd-West), die ebenfalls mit P370 ausgestattet sind. Der SolarEdge Wechselrichter SE7K, an den die Module angeschlossen sind, hat eine feste MPP-Spannung von 750 V. Was in diesem Fall passiert, kann man sich anhand der Kennlinien in den Ergebnissen ganz gut visualisieren. Die Aufzeichnung der Kennlinien kann man in den Programmoptionen unter "Simulation" aktivieren. Ich nehme mal als Beispiel den 01. Juni um 14h. Da wird die süd-westliche Dachfläche mit 1013 W/m² bestrahlt, während die im nordosten nur 75 W/m² abbekommt, da sie im Vollschatten liegt. Dadurch überlagern sich die Kennlinien der Power-Optimizern zu folgender Gesamt-Kennlinie, die der Wechselrichter sieht: Dunkelblaue Kurve: Strom-Spannungs-Kennlinie Hellblau: Leistung-Spannungs-Kennlinie Das Überlagern der Kennlinien läuft in einer Reihenschaltung ja so, dass sich die Spannungen addieren, während die Ströme gleich bleiben. Um die MPP-Spannung des Wechselrichters zu erreichen, braucht man mindestens 13 Module mit P370 Power-Optimizern ( 750 V / 60 V = 12,5 - die 60V kommen von der maximalen Ausgangsspannung der P370). In diesem Fall werden aber nur 10 Module voll bestrahlt, die restlichen 14 auf der nordöstlichen Seite tragen kaum etwas bei. Daher sackt die Leistung knapp über 600 V auf der Gesamt-Kennlinie ab und der Wechselrichter sieht nur noch etwa 1000 W statt der eigentlich verfügbaren 3100 W. Diese Verluste werden dann der Abregelung wegen des MPP-Spannungsbereichs zugeschrieben und sind insofern korrekt. Das zeigt mal wieder, dass der Einsatz von SolarEdge-PowerOptimizern nicht zwangsläufig zu einer Ertragssteigerung in jeder beliebigen Anlagen-Konfiguration führt. Auch hier muss sehr genau (wie bei herkömmlichen Wechselrichtern auch) auf die Verschaltung geachtet werden. Daher wird auch von SolarEdge für die neuen P370 bei 3phasigen Wechselrichtern (wie der SE7K einer ist) eine minimale Modul-Anzahl von 16 vorgeschrieben, um diese Art von Verlusten zu vermeiden. Siehe hier: https://www.solaredge.com/sites/default/files/se-p-series-add-on-frame-mounted-power-optimizer-datasheet-de.pdf Darauf wird bei der Verschaltung in PV*SOL auch hingewiesen, wenn die neuen P370 gewählt werden (die mit worldwide im Namen). Beste Grüße, Martin

Hallo GeromeK, wäre es möglich, uns die Projektdatei zukommen zu lassen? Gerne hier im Forum per private message, danke. Viele Grüße, Martin

Hi Patrik, you are right, sorry. The edge numbers are only shown for "Arbitrary buildings". If you select "Edit" on a standard building, you don't see the edge numbering. But the scheme is the same, the first polygon segment that you draw defines your lateral surface/wall/side n# 1 of the building. Then you go clockwise to number the other lateral surfaces/walls. Kind regards, Martin

Hi Patrik, if you right click the extruded building and then "Edit" you'll see the edge numbering. These are the same as used for the textures. Edge 1 is the first edge that was drawn. Heop that helps, kind regards, Martin

Hi Jan, the economic caluclations in PV*SOL are based on the net present value, see the formulas here: https://help.valentin-software.com/pvsol/2019/calculation/financial-analysis/ So, yes, it includes all assets that are part of the LCOE calculation as well, like loans, taxes, operating costs and so on. Hope that helps, kind regards, Martin