Auxiliary electrification in Hybrid Electric Vehicle (HEV) and Plug-in Hybrid Electric Vehicle (PHEV) represents a promising solution in energy management of vehicle. The work presented in the following paper focuses on the design of a controller able to reduce the electrical energy consumption of electrified auxiliaries during a driving cycle. A Model Predictive Control (MPC) is proposed and applied to the air supply system of a PHEV. A comparison of energy consumption between this method and two others (Hysteresis Control and Dynamic Programming) is carried out in order to verify the performance of the MPC controller. Numerical simulations show that this technique allows to obtain a significant gain on energy consumption compared to a standard Hysteresis Control. Furthermore, the difference in term of energy consumption between MPC and Dynamic Programming is weak.