This study presents a practical and simple approach to investigate the energy consumption of a decanter centrifuge during the sludge dewatering process. An experimental plan to measure the energy consumption of the decanter fed with sludge at three different flow rates and different differential speed values between bowl and screw (?n) was carried out. The trend of the energy withdrawn from power supply as a function of the energy consumed by the bowl motor and the trend of the energy drawn from bowl motor as a function of that recovered from the regenerative braking system has been identified. Finally, the consumption of the bowl motor and of the energy taken from the mains as a function of the flow rate has been determined. The results show that the energy drawn from the grid and the energy regenerated by the regenerative braking system is linearly correlated with the energy consumed by the main electric motor and with the sludge feed rate. In addition, as the flow rate increases, the power recovered is about ¼ of that consumed. A high correlation of the developed models has been detected. The models developed can be used to provide valuable information about energy use patterns and can be used to identify areas where energy efficiency measures can be implemented.