dtarin

Slow can be used on any size system, but simulations will extend to multiple hours for large, complex sites. The main difference that I see between slow and fast (modeling projects in US) is that fast will have higher near shading and lower electrical loss, and for slow, it is the opposite. Not always, but I would say more often than not. In total, shading losses are typically comparable for most sites with fast being slightly higher. Sometimes difference is negligible, but depends on the site; less complex and utility scale will have closer figures. More complex sites with topography, smaller sites with severe shading, will benefit more from slow simulation and the increased accuracy with calculating electrical loss. As for when to use, it depends on your position, project, etc. For utility scale in development stages, fast makes sense, and then moving to slow (or at least benchmarking slow) later on when design is closer to final, prior to financing, construction, etc. If the project is small and simulation time is short, I dont see a reason not to run slow for single, one-off estimates. But if you're doing batch runs, running multiple designs, evaluating different components or weather files, in early stage and need indicative numbers, etc., fast is fine. What's more important is understanding the differences and impacts to simulation results (irradiance, shading, production, etc.), and deciding when to prioritize simulation speed over accuracy and vice versa (and knowing if there even exists material differences).

Shading working fine from what I see, 8.0.5.

You've probably already checked, but all objects are selected to be shading objects in their properties menu?

Batch simulating with different tilt and azimuth will provide more accurate results.

This is not applicable to PVsyst. All trackers in the shade scene track at the same angle. Users can force trackers to track at different angles relative to the standard tracking algorithm, but it is still applied globally to the scene. One would need to model each area of interest individually with different forced backtracking angles and combine results. Whether this results in improved production is uncertain.

Yes, it is typical to use the MPPT feature to model mixed blocks and good practice. It doesn't necessarily need to be due to different bin classes, loading ratios are also relevant even with a single bin (clipping is non-linear). This is of course dependent on the inverter in question, design, etc. With regards to representation, what's "significant" is dependent on project details and opinion. A mixed bin design on a single mppt will be more impactful due to increased mismatch losses, which are up to the user to define. Modeling this in PVsyst using the mppt sharing feature and creating distinct sub-arrays allows one to specify mismatch individually, and documenting this in reporting is good practice. If all of these differences are averaged out, is there a difference in production? I am not sure, but it would probably take the same amount of time to model individually as it would to determine these average values and model as a single sub-array.

The best way would be to do everything outside of PVsyst and create manual reports. However, if you want or need to do it inside PVsyst, there are not many options. One way is to adjust the MV Ohmic loss for that subarray. Set an MV ohmic loss for just that subarray to like 155%. You will need to adjust the wire section size most likely to get the length of wire to a permissible length (there is a character maximum). This example was three symmetric blocks, I didnt fine tune the percentage loss, it is approximately 1/3 loss. Define the ohmic loss as typical for the other subarrays.

PVsyst will often (or always?) default to using the highest GCR under the backtracking menu if you have not selected which tracker(s) to use for backtracking, even if there are only one at say 0.411 vs 0.410. In the shade scene, go into the backtracking menu under tools to select the appropriate tracker for backtracking. There are different options, you can select an individual table (at the pitch you want) or automatic.

Express the report to second decimal to get clear picture, losses could be near zero and are being rounded.

If there are no trees or objects that shade the modules, backtracking is on, and your system is flat, it will not have electrical shading loss.

No electrical shading loss is showing. If these are bifacial c-Si, you'll want to include electrical effect (modeled according to strings) and then make the comparison.

Manually move the modules and objects over the image and line things up that way

Add an object in the PVC file like a tree line or houses

GlobInc = POA