Abstract

This paper evaluates the potential role of fusion in decarbonizing the US power sector in the year 2050. This is done by breaking the US electricity system into regions to understand factors that favor or disadvantage fusion. Fusion is economically competitive in all regions at a grid emissions intensity cap of 20 gCO2-equiv/kWh and lower. As the emissions ceiling lowers, fusion penetration quickly increases, reaching 15%–35% of regional system capacity at 15 gCO2-equiv/kWh. The dispatchability of fusion is valuable as it operates seasonally, with its highest monthly output occurring in the summer and lowest occurring in the spring. Because of this, fusion competes most directly with low-carbon dispatchable options (geothermal and natural gas with carbon capture) and long-term energy storage technologies (pumped hydro storage). Fusion is economically competitive when deep decarbonization is targeted and when land availability is limited.