Environmental Assessment of Fusion Reactors by the Calculation of CO₂ Emission Amount

Abstract

  Comparative studies of environmental burden have been made for fusion reactors based on different confinement systems and blanket modules by calculating CO₂ emission amount. The confinement systems of fusion reactor considered in this paper are the Tokamak reactor (TR), helical reactor (HR), and spherical Tokamak reactor (ST). Several blanket modules such as Li/V, Flibe/FS, and LiPb/SiC blankets are evaluated under the condition of 1 GW electric power output and specific beta values. The calculated amounts of CO₂ emission from fusion reactors are 9.2-11.3 g-CO₂/kWh. This range is the same as that of emission from hydraulic power and atomic power plants which are regarded as clean energy sources now. A substantial amount of CO₂ is emitted from superconducting magnet systems. TR and HR, which use large superconducting coil systems, emit much CO₂ as a whole. If we adopt a higher beta design, the demand on coil systems is relaxed and better fusion reactors emitting less CO₂ can be constructed.