  We develop a Fermi-liquid based approach to investigate the power output of
nano devices in the presence of strong interactions and resonance scattering.
The developed scheme is then employed to study the power output of a SU($N$)
Kondo impurity at the strong-coupling regime. The interplay between Kondo
resonance and the filling-factors in the SU($N$) quantum systems is found to be
a key to enhance output power. Such enhancement results an output power
corresponding to $50\%$ of the quantum upper bound. We demonstrate that given a
proper tuning of the electron occupancy, the investigated power grows linearly
with degeneracy of Kondo state ($N$). This relation can hence be exploited to
obtain output power that is larger than the one in existing non interacting
setups.
