Hi O_Plata,nThe driving point approach is correct. However there are errors in your understanding the energy approach which has led to the discrepancy you see.nThere is only 1 form of energy, SENE=KENE, with thermal energy (TENE) being 0 as this is not a thermal analysis. The KENE and SENE are equivalent with any kinetic energy being stored as elastic potential energy (SENE) when the velocity is 0. Therefore, look at one energy result, SENE or KENE.nYou need to combine the real and imaginary components of the SENE across the frequency domain in a SRSS fashion. This is essentially an amplitude result which can be requested in the mechanical postprocessing environment. Once you have done this you will see that the energy approach matches the driving point approach.nn