A Study on the Modal Shift for Environmental Problem

Abstract

The purpose of this study is to propose that modal shift is effective as an environmental countermeasure. Therefore, we present the optimal modal shift pattern considering environmental problems. In such research, it is necessary to consider the emission of pollutants though overall energy flow, from the input process of primary energy to energy consumption. In other words, it is essential to focus on import, conversion, transportation, and consumption processes of energy in addition to dealing with the physical distribution process. An "energy input-output model" that clarifies the overall energy flow is presented in our study. This model consists of energy input, conversion, transportation and consumption sectors. Bi-objective linear programming is used to formulate a model which minimizes the emission of carbon dioxide and nitrogen oxide. The optimal modal share of freight transport, which minimizes NO_x and CO_2 emissions considering the overall processes of energy flow, is identified in this analysis.