We estimate the amount of energy growth consumed by the Internet infrastructure in Japan for the next two decades. We developed four scenarios for the next two decades that combine various emerging technologies, such as optical circuit-switching and content delivery networks, as well as current technologies, such as end-to-end packet-switching. Each technology has an energy consumption model. Our results show that energy consumption based on a packet-switching network will reach 17.49 TWh/yr. And also that a hybrid of packet and optical circuit-switching networks can reduce energy consumption by 67.7 % from that of the current Internet architecture, while a combination of current packet-switching networks and CDN can reduce energy consumption by 22.2 %. When the core-networks are replaced by optical circuit-switching networks, energy consumption in 2030 is reduced by 48.4 %. We conclude that, by using optical circuit-switching networks to transfer large content, energy consumption will stay flat after 2022.