4. Resource Efficiency Quantification of a Long-Life Product Considering Service Activities Through Life Cycle-Using Japanese K-Car as a Case Study

Resource efficiency has been a focus of the society these days in aiming circular economy. Such resource efficiency evaluation is much more important for long-life products, since such products often try to ease large resource usages by long product lives through durable designs. For those products, service activities can be key factors to prolong product lives. The objective of the study is to propose a numerical model to express product value change including effects of service activities. The study assumes that the reasons for product value changes throughout life cycles are deterioration, obsolescence, and service activities. The case study formalized numerical models to simulate value changes of products. The survey data suggested that “maintenance” along the proper timeline can be the best strategy to enhance resource efficiency. Through the study, it was concluded that numerical models of value change throughout product life cycles can be effective in determining guidelines for resource-efficient life cycle strategies.