I have exactly the same problem, the differences are quite small but it still can have a real economic impact on our studies. I can detail more what I did. So, I ran a batch simulation with ticking the box "Create hourly files", then I set my output files to "Monthly values". My batch simulation is about to simulate over 10 years of functioning, so my only parameter is "Year of simulation". After that I just compared the different values of the variable "Energy injected to the grid", and the results are :
0 43229 43220
1 43166 43151
2 43040 43017
3 42894 42882
4 42729 42729
After that results are the same, but so for the first years there are some differences, which can also be noticed at month level. For information, I just let the default values for the degradation over the years and I ticked the box "Keeps calculated mismatch values".
So my question is the same than sailerthomas, how is that possible ?
Thank you for your answer,