Linda Thoren

Dear Mohamed, You can find a template for the PVsyst format for the Horizon file in the folder “templates” in your workspace. The format Horizon file should contain one line per defined point. Each point defined as an Azimuth and a Height value, expressed in degrees. You would either have to completely restructure your TMY hourly data, going from -180 to 180 degrees with corresponding height values, or import the horizon from web sources. If you wish to use the meteorological data from your site, you can do so by importing your file as a Custom file. You do this by opening Databases, Custom file, choose your Source file and go through the necessary step to do the conversion to import your site. Once saved in your workspace you can use this your created site in your projects. Regards

Dear Angel Mlga, Indeed it seems to be a problem here that I do not have a direct answer to. To address this, I recommend exporting your project as a zip file and sending it to support@pvsyst.com. This way, we can examine your system and provide the assistance you need. Regards

Dear Dominik Damberger In most cases, the open-circuit voltage (Voc) of a PV module will increase as the temperature decreases. This phenomenon is known as the temperature coefficient of voltage, and it's a fundamental characteristic of solar panels. However, at very cold temperatures, such as those below -20°C, will have adverse effects on the performance of a PV module because of mechanical stress on the components etc. The Temperature coefficient is defined by the manufacturer. So, while the temperature coefficient generally causes an increase in Voc, at temperatures below -20°C, other factors related to extreme cold can impact the overall performance and efficiency of a PV module.

Dear Michalis Angeli, In the Wiring layout you should define the average length for one string (blue) and the distance to the main box to the inverter (green). If you have multiple strings and/or inverters this will be reflected in the Global array and the Field global wiring resistance. See example below. It is this number that will be used in the simulation. If you wish to simulate a more pessimistic scenario, to be on the safe side, you can artificially increase the Loss fraction at STC to, for instance 0.8%, compared to the calculated values of 0.65 from the example.

Hello, Adding transformers results in a reduced current load for each individual transformer. The Loss fraction at STC thus decrease at each transformer, but to evaluate the entire system you have to run a simulation and look at the loss diagram.

Dear Michalis Angeli, There are no default values for the output parameters of an inverter, as these values are contingent on the specifications of your inverter model. Consult the inverter’s data sheet to see its specification.