DE superheater /Heat pump in the chiller

In respect of Chillers :
Use of de superheater for hot water generation or Heat pump for Hot water generation may result in higher power consumption.
How it can be designed to derive max eff of CHILLER ,better COP,
What are the parameteres governing the cut-off line for efficiency?
One thing remains that energy is getting converted from one form to the other & what matters therefore is prevention of losses & recovery of losses.
How this can be effectively tackled?