The work deals with the issue of measuring and evaluating the energy intensity of selected processes of machining metal and wood materials. Machining processes are analysed in terms of energy intensity of individual operations, structural and functional components. Thework is compiled as a set of published scientific articles supplemented by an introductory theoretical commentary summarizing the results obtained in experimental measurements.The introduction deals with energy consumption in industry. It summarises the international interests in reducing or transition to renewable sources. The second part describes the machining process based on energy consumption models, which can be used to predict andoptimize consumption. Cutting power is characterized here as the main component of the energy required to remove material from the workpiece.The third part of the work is devoted to the methodologies of monitoring the energy consumed for machining in terms of the possibility of measuring the force effects during machining or electrical quantities in the supply wires to the electric drive of the machine tool. The possibilities of obtaining information about the cutting power are divided into three areas:measuring the current and voltage in the supply conductors, measuring the forces and torque and analysing the properties of the electrical network.The fourth part of the thesis contains an overview of the influence of factors on the energy intensity of metallic and wood materials available in the current scientific literature and experimentally identified and verified in author`s own scientific work. In this part there is ananalysis of the influence of parameters on the cutting power in planar milling of natural and thermally modified wood, where the energy intensity was measured using a power analyser and a frequency converter.The conclusion summarizes the findings that the greatest impact on energy intensity have powerful electric drives of cutting and feed mechanisms, stating that when reducing energy intensity, it is necessary to take into account other factors such as production capacity or quality of the created surface.The appendices to this work are publications in foreign and domestic journals, in which the results of author`s own scientific work have been published.