Comparison of Water Footprint for Industrial Products in Japan, China and USA

Recently, water scarcity has received attention. With the development of industries and the growth of population, the amount of water use has increased. In order to evaluate the water use of industrial products, the method of estimating water footprint (WF) has been developed. WF is defined as the amount of water use during the lifecycle of products or services. In this study, we estimated WF of industrial products in Japan, China, and the U.S. using input-output analysis. It was found that WF for BOF crude steel in Japan was estimated as 0.62 m3/t, whereas WF for EAF crude steel in Japan was estimated as 0.85 m3/t. WF of crude steel in China was estimated as 0.99 m3/t. In the U.S. the pig iron, crude steel and ferroalloy cannot be divided into each sector, so we cannot compare the results of the U.S. to those of Japan and China. In WF for a passenger car, the indirect water use dominated their WF in all countries. To compare the results in each sector between countries appropriately, consistency of industrial sector in the data for water use is required.