2020 年 55 巻 8 号 p. 497-510
This paper proposes an upgrade planning method of Upgradable Product Service System: Up-PSS. The purpose of this study is to obtain upgrading cycle, number of necessary generations, profit rate, and available cost and environmental load amounts which can attain the lower environmental load, lower price, higher profit, and lower service receiver’s dissatisfaction concurrently compared with existing business models. Previously proposed method derives upgrade plan from the viewpoint of functional improvement without considering environmental and economic aspects which strongly relate to sustainability. Therefore, this study aims to develop planning method and evaluation models of sustainability factors. In particular, this paper proposes evaluation models of cost, environmental load, and receiver’s dissatisfaction which consider their temporal value change to obtain aforementioned design solution. This paper applies proposed method to design problem of packaged-rental business model as a case study. The result of case study which attains the lower environmental load, lower price, higher profit, and lower dissatisfaction compared with replacement case shows the availability of proposed method.