Integrated methodology for the evaluation of the energy- and cost-effectiveness of machine tools

Sustainable machine tools are characterized by less consumption of energy as well as low costs during their life-cycle. In order to design such machine tools an evaluation of the energy-efficiency and the costs incurred is needed. In contrast to this, up to now there has been no fully developed evaluation method relating to both technical and cost efficiency of machine tools. Thus, the paper presents an integrated approach for the evaluation of machine tools consisting of methodological proposals for the measurement of energy consumption, modeling of energy flows and simulative analysis of the energy saving potentials as well as an energy-oriented life-cycle costing concept. Additionally, braking energy storage systems and reactive power compensation are analyzed. Based on the identified energy saving potentials, it is shown that at present only reactive power compensation is economically profitable under given assumptions.