EMF SR 5: Comparative Analysis of Energy Intensity Between the U.S. and Japan
Amidst growing concern about global warming, energy conservation has been recognized as a cost-effective way to reduce emission of carbon dioxide. It is considered that the United States has a big potential for energy conservation based on a comparison of energy intensity. Energy intensity is commonly measured by Total Primary Energy Requirement (TPER) per Gross Domestic Product (GDP). Energy intensity of the U.S. has been about 1.7 times as much as that of Japan since 1983. However, this number does not reflect the true differences in the efficiencies of energy consuming technologies; the contribution of non-technological factors such as climate, population density, life styles, or industry mix must be considered. In this study, the structure of energy consumption in the U.S. and Japan, and the contribution of non-technological factors to the differences in energy intensity are analyzed in detail. As a result of quantitative analysis performed here, energy efficiency in Japan is superior to that in the U.S. even if the contribution of non-technological factors is removed. Adjusted TPER/GDP ratio in Japan would be about 74% of that in the U.S. in 1989. Non-technological factors are expected to contribute to about 41% of this difference with the transportation sector comprising quantitatively the largest share in the non-technological differences. It is expected that there is large potential for energy conservation by technological renovation in the U.S. manufacturing sector. On the other hand, it is supposed that the differences in life styles and living standard affect higher energy use in the U.S. residential sector significantly and it is difficult to reduce the gap between the U.S. and Japan. Furthermore, a new standard, which measures nation energy intensity, is proposed. Considering the production aspect of GDP, energy consumption in the residential sector and private transportation sector is excluded. Based on this standard, adjusted TPER/GDP ratio in Japan is about 81% of that in the U.S. In other words, the lower the efficiency of energy consuming technologies in the U.S. results in about 19% more energy consumption than in Japan.