Linda Thoren

The tutorial is from version 7, but the functionality is the same in version 8. For your inverter, you either define "Pnom sharing withing the inverter" or "independent MPPT inputs". Indeed, in every sub-array you have to define how many strings you have in parallel. You can not define strings of different lengths in 1 MPPT.

Hello Lukas, It is indeed possible to create a sub-array for each MPPT and in general you are not forced to choose one inverter per orientation. You can even mix two orientations in one MPPT as long as you have at least one string in each orientation Assuming you are importing your 3D scene from another software, creating full tables instead of individual panels is normally done in the external tool. Instead of defining each individual panel, define the complete area of the table (including the spacing of between the panels) and PVsyst will fill the tables with the amount of panels that can fit in that specified area. This would create 14 tables in your scene.

Hello, The Unlimited Sheds field type in the orientations management cannot be combined with the 3D scene, since you already will define layout parameters such as the number of tables, pitch etc. You can indeed define a fix tilt plane and instead define the layout in the 3D scene. The model that will calculate the bifacial gain is 2-dimensional calculation - similar to the unlimited sheds orientation and the layout parameters needed can be defined in the 3D scene or in the unlimited sheds in the orientation window.

Hello, Indeed, your understanding seems to be correct. For Amorphous panels, you will find the parameters regarding the spectral correction in the .PAN file (Model parameters Spectral correction and the tick-box is activated). If you use a panel in the Sandia database (you can find relevant panel in the databases and in the "Availability" filter choose Sandia DB) you will have a choice to apply the Sandia model. PVsyst provides the option to apply the spectral correction model, developed by First Solar. While this model is particularly relevant for First Solar modules, users may choose to apply it to other technologies at their discretion.

Hello Mariyam, The the percentage of grid consumption in the loss diagram shows how big portion of the time you are consuming from the grid. In the bottom of the graph it is indicated how much energy is consumed from the grid. For example, if the electricity consumption is far larger than the PV production, you will have grid consumption 100% of the time, and still have self-consumption to user from solar.

Hello, The two print screens in my post comes from the same report (version 7). A simulation in version 8 would normally look the same. Kind regards

Hi, Indeed if you have no other shadings this solution would give a rather representative scenario of what you wish to simulate.

Hello, Sorry your goal is not really clear to me. In the headline you indicate that you have 22 strings with 34 panels in series and 1 string with 33 panels in series (a total of 781 panels). If your inverter has 6 MPPTs you could for instance create 3 sub-arrays with the following configuration: sub array 1: 4 MPPTs 16 strings of 34 (4 strings per MPPT) sub array 2: 1 MPPT 6 strings of 34 (6 strings per MPPT) sub array 3: 1 MPPT 1 string of 33 It is important that the number of strings is a multiple of the number of MPPTs The following youtube tutorial further explains the multiple MPPT feature and the power sharing:

This is further explained in the following help page: https://www.pvsyst.com/help/project-design/bifacial-systems/index.html#irradiance-on-the-rear-side-view-factor

Hello, Is your simulation for year 1? In that case it seems to match well with just some rounding differences of 0.01%

Hello, High annual variability indicates that weather conditions can differ significantly from year to year at this site. The purpose of running a P50-P90 analysis is to account for these uncertainties. Therefore, it is not recommended to customize the weather data variability, though you do have the option to input custom values if needed.

Hello, It is not possible to mix orientations in a string. It is possible to mix orientation in an MPPT, given that there is at least one string in each orientation. You find more information about this in the following PVsyst help: https://www.pvsyst.com/help/project-design/orientations-in-v8/mixed-orientations.html It is not possible in PVsyst to have empty MPPT inputs.

One way to evaluate such a system could be to choose the increased self consumption storage strategy and create a self consumption profile that corresponds to the energy you intend to inject to the grid. With the self consumption strategy, the batteries will never discharge to the grid, only to fulfill the users needs. Though, if you create a consumption profile with large consumption during the night you could possibly considered the energy that is "self consumed" to be what you inject to the grid. Let me know if this work around seems to be valid in your context. Kind regards

Hi Alex, The Unlimited Sheds field type is aimed for large regular systems with several rows assumed to be sufficiently long (unlimited) sheds so that we can neglect the edge effects. For only one table you must choose the field type Fixed tilted plane. Indeed it is not possible to simulate a bifacial system with a single row, though this is on our roadmap. The bifacial calculation in PVsyst is based on a 2 dimensional representation, calculating how much irradiance is falling between the tables and how much will be scattered up on the back side, thus there has to be a pitch. A possible workaround is therefor to create a 3D scene with your table and then duplicate this scene further away so that PVsyst can detect a pitch. Verify that the tables are well aligned so that indeed PVsyst detects the pitch in bifacial window. Note that the amount of tables in the 3D scene will be double what you have defined in the system and this will create a warning. You can increase this limit in the advanced parameters. In the first PVsyst welcome window, click “Settings” and “Edit advanced Parameters” and find the parameter that triggers the error message – “Shadings: absolute maximum shading/field area ratio”. This will allow you to run the simulation Kind regards

Hello, Indeed, in PVsyst version 8 you are able to define separate bifacial models, one for each fixed tilt or tracker orientation. However, dome configurations are not yet covered by this update. We will work on it for a future minor release.

Hi, What exactly are you trying to model? Are you focusing on production during peak demand hours or the price difference between on-peak and off-peak periods? In the economic evaluation, you can define different prices for on-peak and off-peak periods. You can also always generate an hourly output file with the relevant parameters and analyze the data in Excel or other external tools.

Hello Andrés, Please note that the language in this forum should be English. You can find a detailed explanation of all the possible inputs and parameters for the economic evaluation in the following YouTube tutorial: Kind regards

Hello, Indeed both GlobInc and GlobEff will be in the collector plane at the position with backtracking if backtracking activated. You can export also the phi angle to verify the position of the trackers every hour.

Hello, Indeed, if there is no production, the temperature of the modules are simply not calculated and put to 0. This has no impact of the result of the PV production since no thermal inertia is considered for the hourly simulations. For a more elegant output file we will considered changing this approach. For your evaluation you could consider the 0 as null and exclude from your average, or replace them with for instance the ambient temperature. Thank you for your input.

Hello, In general, you can define multiple MPPTs per sub-array (as long as you have a multiple between the number of strings and MPPT inputs). Indeed you have this constraint in the current version that you can not have empty MPPT inputs. To get around the constraints in PVsyst, you could modify the number of MPPTs in the OND file, though this might impact other behaviors of the inverter and you should adjust all the parameters to correspond to the use-case you are referring too. The following youtube video further explains the MPPT and Power sharing:

Hi, No it is today not possible to include that in the original simulation. If you choose to simulate both sides as front sides, that can indeed be simulated in the same variant (with the proposed work around of modifying the .PAN files) You are right, the thermal losses only consider front side irradiance, we will look into this. Kind regards

Hello Luis Zimmermann, In PVsyst, the beam and diffuse components and the rear side of a vertical bifacial PV system are calculated similarly as on the front side, by computing the integral of the visible sky. For the rear side irradiance, this is done using a 2D intersection method, same as the "unlimited shed" field type. If the layout is done in the 3D scene, the visible sky is instead in 3D. With bifacial systems, the view factor model also estimates the contribution of ground reflection to the front and rear side (not considered in mono facial simulations).

Hello, In the economic evaluation, you can include hourly tariffs to assess the financial benefits of a peak shaving strategy. You can in the peak shaving strategy specify the hours when you allow for the battery to discharge and inject to the grid and calculate the revenue based on the corresponding tariff rates. However, the system does not work in reverse—economic data cannot be used as an input to control battery storage behavior.

Hello, Indeed the peak shaving is not design for this exact purpose. With the peak shaving strategy you will only store the energy above the set grid limitation. Setting a lower grid limitation will allow to charge the batteries and then you can set the specific hours for when you want to discharge the batteries. Indeed the discharge of the batteries will also be limited to the set grid limitation threshold.

If you have less production, there will be less energy to charge the battery with, no matter the size of the battery. But it could indeed also depend on the charging and discharging power