The Development of Fuel Economy Regulation for Passenger Cars in Japan

Increasing the energy efficiency of cars, resulting in improved fuel economy, has received attention from time to time in various regions of the world. The main driving forces – today and historically – have been increasing energy prices and concerns about exhaust emissions. Reduced fuel use implies both lower fuel cost and lower emissions of carbon dioxide (CO₂). Due to the increasing attention these driving forces receive worldwide, fuel economy improvements form the basis for car manufacturers’ competitiveness in the global market. Fuel economy regulation is no doubt one of the factors that influence, direct and strengthen the fuel economy of cars, and such regulation has hitherto been implemented at regional or national levels. A prominent example is Japan, which plays a dominant role in the car industry while also having a strong tradition of fuel economy regulation.