Japan’s Highly Energy Efficient Transportation Sector: Is It Possible for the US to Replicate?

A massive amount of energy could be saved if the United States’ transportation sector had the same energy efficiency as Japan’s. In fact, according to a new study, Japan’s CO2 emission per capita for passenger transportation is only about 30 percent of that in the US. Could it be possible, then, for the US to take Japan’s transportation energy model and achieve substantial energy savings?

In their article “Energy Efficiency in the Japanese Transport Sector,” Phillip Y. Lipscy and Lee Schipper analyze Japan’s transportation sector and argue that Japan stands out in transportation sector energy efficiency primarily due to low activity levels and modal structure, which is largely correlated with geography, urban population density, and political context. Therefore, simply copying Japan’s model will not help the US save substantial energy in the transportation sector.

Phillip and Lee begin to analyze Japan’s transportation sector energy model by dividing transportation into passenger and freight sectors. Passenger transportation consumes about 60 percent of the total energy spent on transportation, while freight consumes the remaining 40 percent. Subsequent analysis is focused on the passenger transportation sector. The authors introduce an analytical framework and decompose the energy consumption into three different components: activity, structure, and intensity. Activity represents the volume of transportation, structure represents the different modes of transportation, and intensity measures the CO2 emission per activity.

The authors find that the difference in energy consumption between the United States and Japan primarily comes from the activity and structure components. In the activity component, passenger travel per capita in the US is about 2.5 times greater than that in Japan. The most obvious explanations for this are Japan’s smaller geography and higher urban population density. Structure is another factor that contributes to the energy consumption difference. In 2008, cars accounted for 55 percent of all passenger activity in Japan while this figure was 88 percent in US. The share of rail transportation in Japan is 30.9 percent compared to 0.6 percent in the US. Since rail is more energy efficient than cars, structure plays an important role in the energy consumption difference. Japan and the US almost have the same level of energy intensity by mode, however. The US is slightly more energy efficient in air, while Japan is more energy efficient in train and car. Even though Japanese cars are more fuel efficient, congested traffic greatly increases the fuel consumption on the road and leads to the nearly equivalent energy consumption between the US and Japan.

Japan’s political context also plays an important role in its transportation sector. The authors note that, after World War II, the political arrangements in Japan made it attractive for politicians to make automobiles expensive for Japanese citizens to drive. Automobiles have high taxes and highway tolls, and the resulting revenue is redistributed to the core supporters of the Japanese ruling Labor Democratic Party, which reinforces the transportation policy. Since the oil shock, energy efficiency became a high priority for the Japanese government. The Top Runner program was introduced to automate improvements in efficiency by setting target improvements based on the product with the highest efficiency performance in the market. Also, lower tax rates and highway discounts are given to kei cars, which are more energy efficient than regular cars, to promote energy conservation.

Although Japan’s transportation sector is more energy efficient than that of the US, it is primarily due to activity level and modal structure. The energy intensity by mode is similar between Japan and the US. Since travel level and modal structure are greatly influenced by factors such as geography, urban population density, and political context, it cannot be changed only through transportation policies. Therefore, it is unreasonable for the US to replicate Japan’s transportation sector energy model. However, the US can follow Japan’s steps to adopt policies that promote energy efficient cars, as cars account for 88 percent of the total passenger activity in the US.

Article Source: Phillip Y. Lipscy and Lee Schipper, “Energy Efficiency in the Japanese Transport Sector,” Energy Policy 56 (May 2013): 248-258.

Feature Photo: cc/(Matthias Harbers)