ideal contribution = 0 during solvation energy calculation?

I have calculated the solvation energy of formaldehyde in different solvents like benzene, DMSO, I have followed the same method of the tutorial " solvation energy of propanoic acid in octanol" but I am unable to see the ideal contribution of energy (= 0 ​​​​​​​KCal/mol) in all these output files. can anyone let me know why soo?