A comparative analysis of the environmental impacts of machine tool manufacturing facilities

Manufacturing accounts for 37% of the global energy demand. Few researchers have conducted a holistic energy assessment of factories where energy beyond production equipment is accounted for, and environmental impact assessments of machine tool manufacturing are even more limited. All the while, factories need to understand where energy is used, how to allocate it to their products, and where savings lie. This paper quantifies the energy consumption and greenhouse gas emissions of a machine tool manufacturer located in Iga, Japan. Six plants within the factory are investigated whose primary operations range from precision machining to product assembly. Furthermore, a model of the energy consumption of each plant's HVAC system is developed and used to evaluate the environmental impacts and operating costs at alternative sites in China, Germany, and the US. Location was found to have a significant influence on the environmental impacts and resulted in changes in the annual energy consumption relative to the Iga baseline that ranged from 10% to 8%. Additionally, opportunities for improvement were identified by comparing the energy intensities of the equipment within the plants to industrial averages. Since the plants in this study use widespread manufacturing processes and varied climates were investigated, the methods and strategies that were developed can be extended to other discrete manufacturing facilities to identify opportunities for cleaner production. (C) 2015 Elsevier Ltd. All rights reserved.