Abstract
This study addresses the development of environmental database using Japanese input-output (I-O) tables for Life Cycle Inventory analysis (LCI). Many LCI case studies have been performed using Japanese I-O tables. However, most of these studies have focused only on CO2 emissions due to lack of high quality data concerning other substances that influence the environment. The objective of this study is to supply CO2 and CH4 emission factors of commodities estimated using the latest Japanese input-output table (1995). In general, emission factors are estimated using Japanese I-O table based on the assumption that all commodities are produced in Japan. In this paper, however, a method that permits to reflect the actual activities at the overseas production of import goods is used. The results show, (1) CH4 is not negligible when performing Life Cycle Assessment (LCA) from viewpoint of global warming, and (2) CO2 and CH4 emission factors estimated using the conventional method are very different from those using the method proposed in this paper because of the difference of technologies used in Japan and abroad.
