Hi Meshal,
Can you please show on what basis you say "the thermal energy in storage in 75% of the year exceeds the TES capacity". If you show this in an excel file, probably I can help you. I use TES in Tower, and I have never seen a mismatch between charged and discharged energy except you consider TES fully or half charged in the beginning of the simulations. In this case, the discharged energy from TES can surpass the charged energy.
Regards,
Saeed