Conceptual designs for a European demonstration power plant (EU-DEMO) are based on extrapolations of physics scaling laws and current understanding of engineering limits based on available technologies. It is imperative to quantify the impact of uncertainties in physics and engineering parameters on the ability to produce an economically attractive future fusion power plant that meets key design outcomes. In this work the sensitivity of the expected capital cost of an EU-DEMO power plant has been studied using the systems code PROCESS [1]. A systems code aims to model interactions between subsystems of a fusion power plant and provide consistent solution across a large parameter space. The PROCESS system code allows for user defined initial conditions and constraints and then optimizes using a given figure of merit to find optimal design parameters.
We present a sensitivity analysis on optimizations around the 2018 pulsed EU-DEMO baseline [2], this allows for the identification of the most consequential model parameters and the magnitude of the non-linear interactions between them. We consider the pulsed EU-DEMO baseline and while fixing the major radius and optimizing for fusion gain Q we present a sensitivity analysis of the role of the physics and engineering parameters and constraints in determining the capital cost of such a device. We identify the dominant physics parameter as the power threshold necessary to enter H-mode which accounts for 45% of the sensitivity and find high interactions between plasma shaping parameters and other power plant subsystems. This analysis allows for the identification of areas of additional technical focus and uncertainty propagation.
[1] M. Kovari et al, 2014 Fusion Engineering and Design 89 3054-3069
[2] G. Federici et al, 2019 Nucl. Fusion 59 066013