Energy consumption model and energy efficiency of machine tools: a comprehensive literature review

To cope with the serious situations such as rising energy price, the global resource depletion and climate warming, improving energy efficiency in manufacturing becomes an inevitable trend for energy conservation, emissions reduction and sustainability. As the basis energy consumed device in manufacturing system, machine tools' energy consumption modeling and energy efficiency evaluation are the prerequisite for energy-saving in manufacturing. A comprehensive literature review is needed because some related concepts are not clear and the precision of models still need to be promoted in this field. Firstly, the connotation of energy efficiency for machine tools was discussed. It was pointed out that specific energy consumption referred to the mapping relationship between energy consumption and the processing parameters, which reflected the energy efficiency of machine tools from the perspective of effective input and output. Secondly, design, scheduling management, optimization and environment assessment of machine tools were introduced based on energy efficiency. Thirdly, the existing energy consumption models were classified into three categories in this work: 1) the linear type of cutting energy consumption model based on material remove rate, 2) detailed parameter type of cutting energy consumption correlation models and 3)process oriented machining energy consumption model. Finally, conclusions were drawn for the future study in two major points: 1) the accuracy of current energy consumption models could be improved through introducing the correlation analysis of machine tools, parts, tools and processing condition, 2) more scientific evaluation index system is required for the assessment and test of machining tools' energy efficiency.