The chipper for chips is an energy consuming machine. Many factors influence the result of chipping which influence the whole process. The paper deals with the process of wood chipping by a chipper in order to determine its energy consumption. The main purpose was the determination of input power and comparison of revolution frequency on the outlet shaft of a skidder regarding the dimension of the torque depending on variable parameters which characterize the process of wood chipping during the measurement and the analysis of energy consumption of a chipping machine was carried out.