An approach to integrate parameters and indicators of sustainability management into value stream mapping
In production research, sustainability is discussed in various forms and often combined with Value Stream Mapping (VSM), a highly accepted method in practice for improving production systems using lean principles. In scientific literature, most authors present frameworks for scoring production processes (e.g. ratios, benchmarks). These approaches aim to reduce (material) input for producing a specific amount of goods. Hence, improved target-conditions of value streams can be designed to increase ecological efficiency and therefore decrease costs. However, the main aim of this contribution is to present an approach to combine generally accepted parameters and indicators of sustainability and VSM. This approach is based on process-oriented accounting of resource consumption along buffers, transports and processes along value streams. This model of integrating sustainability into VSM goes conform with international accepted guidelines to prevent disposals of input resources by reuse, recycle and recovery. On the one hand, following international guidelines and frameworks, this approach can be used for sustainability reporting; e.g. calculating emitted solvents per produced part, kilogram carbon dioxide equivalents per produced part (with units [kgCDE] or [kgCO2eq]), kilogram disposals per produced part, etc. On the other hand, companies will be able to calculate costs and revenues of sustainable value streams; i.e. to quantify their efforts and benefits monetary. Hence, it is necessary to immerse into material flows in value stream, material consumptions at processes, energy consumption of transports, buffers and processes in value stream, linkage of processes with scrap rates, creation of waste, etc. New data lines in VSM need to be created to represent the parameters and indicators of sustainability. The research findings will be presented by an use case from automotive industry.