Fusion Power Sensitivity Analysis and Thermodynamic Cycle Selection

Abstract Fusion energy presents a promising alternative solution for the energy transition, with a huge amount of heat being generated across the tokamak. Unique to fusion, though, is the significant loads, with a key part of this being to drive current in the plasma and cool the magnets to cryogenic temperatures. This, coupled with the energy lost in the thermodynamic cycle and other smaller losses, such as those to power the fuel cycle, will determine the net energy produced by a fusion plant. This paper seeks to outline the current understanding of these loads, and highlight the workflow and trade-off required in the system particularly around materials choices and so-called breeder blankets, which drive much of the thermal energy capture. The technology choice for breeder blanket often focuses on its function as a fuel breeding module to enable self-sufficiency, while here this selection is viewed instead from the lens of the power generation system. Blanket technology that enables compatibility with preferred materials and temperature for the thermodynamic cycle of choice is outlined with optimising for this aspect in part being at odds with other functions of this blanket technology. The trade-off space is then explored, with potential options for navigating it outlined. This paper reviews several thermodynamic cycle solutions, highlighting the relative merits of different approaches to integrating power generation within a fusion power plant conceptual design.