Abstract

The Japanese government has expressed that Japan intends to become a #x201C;hydrogen society#x201D; where homes and fuel-cell cars are powered by hydrogen, which is regarded as the CO2 emissions-free energy source, and has laid out plans for a #x201C;hydrogen highway#x201D; peppered with fueling stations, all in time for the Tokyo 2020 Olympics [1]. And also, a remarkable development of Fuel-Cell Vehicles (FCVs) has been achieved; for instance, Toyota#x2019;s FCV, #x201C;Mirai," which launched in 2014 after two decades of tireless research, recently rolled out in the US and Europe. This situation may give many people an impression that a #x201C;hydrogen society#x201D; will come true in the near future. But is this really true? In fact, there are so many difficulties to overcome before a #x201C;hydrogen society#x201D; is realized.