One of the major goals of automotive industry in recent years has been the improvement of the energy efficiency of vehicles, due to the increasing energy costs and the restrictions on emissions. This thesis investigates the potential in fuel consumption reduction of a 48V P1 mild-hybrid IVECO Daily equipped with an Eco-Adaptive Cruise Control (Eco-ACC). From the energy analysis of the powertrain on different driving cycles, a major contribution to fuel usage is due to high torque requests in correspondence of high acceleration and deceleration. Fuel consumption strictly depends on driving behaviour and therefore one of the strategies to increase efficiency is to adjust the driving style by using Advanced Driver Assistance System (ADAS) to enhance eco-driving.