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Last day of SolarGIS data doesn't get imported


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PVsyst is not importing the last day of an hourly SolarGIS weather file when the timestamps are stored as decimal values. This problem exists in both version 6 and 7 (I was using 6.8.7 and 7.0.17). Below is a detailed description of the problem:

A customer provided me a SolarGIS TMY weather file containing hourly data. The columns included the day of the year (1-365), the time of day (in decimal format), GHI, DNI, and other parameters.

I imported this file using the hourly SolarGIS format. After importing, I did NOT get a message saying the file had been created or an additional message asking me if I wanted to view the hourly meteo file.

Next I went to view the monthly GHI and DHI totals for the meteo file. The table looked normal except for the month of December, which was highlighted and showed "(30 days)" next to the month of December (screenshot attached). I then looked at the daily totals and confirmed that the GHI and DHI were both zero for December 31st.

I then opened the source CSV file and confirmed that the dataset was complete, having data for 8760 hours and 365 days. I totaled up the monthly GHI from this file and confirmed that the December GHI from the CSV was higher than the December GHI from the PVsyst meteo.

To figure out what was going wrong, I compared the SolarGIS file that wasn't importing correctly to a different one that had previously been imported successfully. I found out that the good SolarGIS file had timestamps that were specified as hours and minutes (e.g., 0:30, 1:30, 2:30, ... , 12:30, 13:30, 14:30, etc.), while the bad SolarGIS file had timestamps as decimals (0.0208, 0.0625, etc.). I changed the decimals to hours and minutes, and was able to import the file successfully.

I think this is an issue with PVsyst as opposed to SolarGIS. As far as I'm aware, the customer did not modify the SolarGIS CSV file prior to sending it out. Additionally - if PVsyst wasn't able to import data with decimal timestamps, you would think that it would fail to import any data at all, as opposed to importing all the data except for the last day.


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