Potential contribution of fusion power generation to low-carbon development under the Paris Agreement and associated uncertainties

Fusion energy has abundant resources, does not exhibit nuclear runaway, and it has zero-carbon emissions. Long-term strategies for fusion energy development will become critically important to promote future DEMOnstration Fusion Reactor (DEMO) projects by another largescale investment and gain social acceptance. This paper assessed the potential contribution of fusion power generation to low-carbon development, which is prescribed in the Paris Agreement, under the combination of different uncertainties of future socioeconomic development, probability of the 2 °C target, and development of commercial fusion power plants. Global negative CO2 emission in 2100 by drastic decarbonization of energy systems was required to achieve the 2 °C target, and fusion power plants were expected to be installed in the latter half of the 21st century mainly in countries with limited potentials of zero-emission energy sources, such as Japan, Korea, and Turkey, for cost-efficient climate change mitigation. If inexpensive power plants could be developed by enhanced R&D and advanced design in DEMO projects or if the establishment of fission plants in the future is low, fusion power generation will also be deployed in the EU28, India, and China. Further cost reduction by innovative design and alternative concepts are also essential to diffuse fusion plants in zero-emission resource-rich countries.