Energy equivalents to quantify the total electricity consumption of factory-integrated machine tools

Energy efficiency in industries is one of the dominating challenges of the twenty-first century. Since the release of the first eco-design directive 2005/32/EC in 2005, great research effort has been spent on the energy efficiency assessment for energy using products. A missing piece for finalizing the ISO 14955-2 is the quantification of a machine tool's non-electric power demand due to external support systems such as compressed air systems, water cooling systems, air conditioning systems, and exhaust air systems. These systems are comprised to the technical building service and cause additional electrical power demand that can be assigned to a machine tool. A model is set up that links the machine tool and the technical building services. The model enables to deduce the electrical power demand of the technical building service caused by non-electric power demand of a machine tool using electrical energy equivalents. Hence, the total electrical power demand caused by a factory-integrated machine tool can be derived. The applicability of the model and the electrical energy equivalents is proven in a practical case study on a grinding machine.