External costs of silicon carbide fusion power plants compared to other advanced generation technologies

This study was performed in the framework of the Socio-Economic Research on Fusion (SERF3), which is jointly conducted by Euratom and the fusion associations. Assessments of monetarized external impacts of the fusion fuel-cycle were previously performed (SERF1 and SERF2). Three different power plant designs were studied, with the main difference being the structural materials and cooling system used. The key variables and factors that significantly contributed to the value of externalities in the fusion fuel chain were identified and a set of design criteria and recommendations on how to reduce the external costs of fusion power was produced. In this third phase of the SERF project the external costs of three additional fusion power plant models using silicon carbide as structural material have been analyzed. External costs are those costs imposed on society by the fuel cycle but not reflected into the price of the electricity generated. This study has evaluated the external costs of three different power plant designs using silicon carbide as structural material. A comparison with other advanced generation technologies expected to be in use around 2050, when the first fusion power plant would be operative, has also been performed. These technologies include advanced fossil technologies, such as pressurized Fluidized Bed Combustion and Integrated Gasification Combined Cycle with carbon sequestration technologies; renewable technologies including fuel cells, photovoltaic systems and geothermal energy with energy storage devices and advanced fission reactors. The study uses a methodology for evaluating, in a standardised way, the external costs of electricity generation by different fuel cycles previously developed by the Commission of the European Union in the frame of the "ExternE" project. The ExternE methodology is a bottom-up methodology, with a marginal and site specific approach. Quantification of impacts is achieved through the damage function or impact pathway approach that follows the sequence of events linking a burden to an impact and subsequent monetary valuation. This means that it involves siting a power plant, and calculating its contribution to the environmental and health situation locally, regionally and globally. Fusion power plants using silicon carbide as structural material have higher efficiencies than plants using steel and this fact has a very positive effect on the external costs per kWh. External costs of these plants are in the lowest range of the external costs of advanced generation technologies indicating the outstanding environmental performance of fusion power.