Value stream maps for industrial energy efficiency

Lean thinking is an engineering approach to avoid non-value adding tasks or processes in manufacturing. Most of the lean studies in the energy field are focused on savings in manufacturing processes. This paper suggests a futureoriented energy value stream mapping approach that aims to improve energy efficiency in small- and medium-sized manufacturing companies. Energy value stream mapping is a graphical technique that allows identifying the level of energy use and, thereby, discovering saving opportunities at each step of different processes either in production or in facility support. To analyze the possible outcomes of improvement options, future scenarios are developed using Bayesian networks. The suggested model can be used not only for diagnostic purposes but also for energy budgeting and saving measures. An application is given to demonstrate the use of energy value stream maps (E-VSMs).