Energy–materials nexus of electrified vehicle penetration in Japan: A study on energy transition and cobalt flow

Abstract

The penetration of low-carbon technology must be accelerated to achieve carbon neutrality, but can be restricted by the material supply required for the production of such technology. In this study, we analyzed the diffusion of energy technologies from energy transition and sustainable resource use perspectives. An energy system analysis was performed to evaluate the future technology stock, energy balance, and CO2 emissions in Japan. Simulation results show that 79.4% of the energy consumed and 94.4% of the CO2 emitted by passenger vehicles could be reduced from 2010 levels by 2050, if the maximum growth rate of electrified vehicles is 17% per year. Meanwhile, for that scenario, material flow analysis suggests that cobalt demand in 2050 would increase to 93.9–174.0 kt, which is 20.9–35.8 times of that in 2020. Recycling of cobalt waste will reduce the cobalt supply and demand gap therefore is critical for sustainable resource use.