Energy conservation and energy management in the metals industry

Abstract

Statistical analysis shows that energy costs on average are in the range of 20–35% of the production costs in the metal industry depending on the age of plant, working methods, and cost of energy, to give just a few examples. Since processing times can be considerably shortened and unnecessary operations eliminated, it is essential that reorganized routes and their consecutive sequences are carefully controlled. The concept of a coordinated production control can be shown to be a powerful tool for optimizing energy usage; a hierarchical approach in supervision and control enables efficient utilization of the informatics methodology. Energy consumption per unit of product is also dependent on the production capacity. At reduced capacity both heat and power consumption per unit of product tend to increase exponentially. The coordinated operation of the process units makes it possible to avoid idle running and thus reduce energy costs. As an additional saving potential, energy can be stored in intermediate products during a period of cheaper power, e.g. the electricity night tariff.