Sudden Load Profile Spikes After Importing File

[Ady]

Hello,

I defined a custom load profile as per the PVsyst template and imported it into PVsyst. However, after importing, I noticed some unexpected sudden spikes in the preview graph (screenshot attached, seem happen at 00 hour).

• The spikes do not exist in my original input file.

• They only appear after the file is loaded into PVsyst

• The rest of the profile seems to follow the expected trend.

Could you kindly advise what might be causing this?

• Is it related to file formatting, delimiter issues, or data resolution mismatches?

• Are there any best practices to avoid such spikes during import?

Any guidance would be greatly appreciated.

[Linda Thoren]

Hello,

Does the peaks only appears in the preview graphics or is there in issue with the actual values in the input? Does the Annual need and the CSV source file to the left of the graphic correspond to the original file? 

You can possibly try to run a simulation and export the results to verify that the simulation is made with the correct values

[Ady]

pls see below screen shot, the spike seem like happen at the graph...

 

[Linda Thoren]

I notice that you have a warning message indicating that your file contains data for the 29th of February. Are you using weather data for this specific year (a leap year) or a generic year ? Try to take out the 29th of February from the dataset.

[Ady]

hi, able to solve the above issue.. thanks. 

[Ady]

I’m seeing an unexpected overlap in the results for a project with ~6 MWp PV + 5 MWh BESS (see attached screenshot).
Simulation setup: self-consumption with storage; grid injection disabled.

Issue - 1st screenshot
Around late afternoon (≈16:30–18:00 in the attached plot), the curves show “Unused energy (battery full, no grid injection)” and “Battery Discharging Energy” occurring in the same time window. My expectation is that if PV is being curtailed because the battery is full and export is not allowed, the battery should not discharge during that same period unless the load exceeds available PV and the battery can no longer charge.

Issue - 2nd screenshot

"Battery Charging" and "Battery Discharging" accure in the same time window. 

please clarify.

[André Mermoud]

Please remember that we are working in hourly values. And the thresholds according to the battery SOC  may arise during the hour, so that the transition from an operating state to another one may arise during the hour. Therefore you can have a "Battery full" state at the beginning of the hour, and a discharge during the rest of the hour. 

However there is also a visual artefact because you are showing lines from the middle of hour to the middle of the next hour. In your first plot, at 13:30 you have unused energy, but no BESS discharge. At 14:30, you have BESS discharge, but no Unused energy. The intermediate lines don't have any meaning.