Quantitative Assessment of Urban and Industrial Symbiosis in Kawasaki, Japan

Colocated firms can achieve environmental benefit and competitive advantage from exchanging physical resources (known as industrial symbiosis) with each other or with residential areas (referenced here as urban symbiosis). Past research illustrated that economic and environmental benefits appear self-evident although detailed quantification has only been attempted of symbioses for energy and water utilities, This article provides a complimentary case study for Kawasaki, Japan. The 14 documented symbioses connect steel, cement chemical, and paper firms and their spin-off recycling businesses. Seven key material exchanges divert annually at least 565 000 tons of waste from incineration or landfill. Four of these collectively present an estimated economic opportunity of 13.3 billion JPY (similar to 130 million USD) annually. Five symbioses involve utilization of byproduct and two sharing of utilities. The others are traditional or new recycling industries that do not specifically benefit from geographic proximity. The synergistic effect of urban and industrial symbiosis is unique. The legislative framework for a recycling-oriented society has contributed to realization of the symbioses, as has the availability of government subsidies through the Eco-Town program.