Exergy diagnostic methodology for energy management in manufacturing

Abstract

Scope and Method of Study: The focus of this study was the creation of a systematic characterization and identification methodology for potential energy management projects in the industrial manufacturing setting. The current methods of selecting processes for energy improvement processes tend to be experience-based in nature. Most energy improvement software either begins with the notion that the particular processes to be improved have already been identified or that some form of a-priori domain knowledge is needed to identify these processes. The methodology proposed in this study begins with the product value transformations and works outward to establish metrics of process performance (efficiency and effectiveness). The methodology presented in this research can be used as both a process design system and an energy auditing aid.

Findings and Conclusions: A systematic methodology is described that gives the engineer an understanding of the energy use of individual processes at a systems level and uses a more quantitative means for the identification of candidate energy improvement projects. The method suggested uses a combination of an exergy (second law) based analysis and energy value stream mapping to visualize the entire plant process for systems optimization (process integration). The sub-processes with potential for energy conservation are highlighted and may be ranked or otherwise selected by the engineer and management for action. The methodology also is poised to act as an integrator with other process analysis methodologies such as activity based management, lean manufacturing and sustainability studies. The expansion of this integration role is suggested for further research.