The Fusion to Hydrogen option in a carbon free energy system

To face climate change and keep the global temperature increase within 1.5°C above pre-industrial levels over the long term, ambitious climate policies are needed to progressively decarbonize all the sectors of the economy. In the power sector, the share of solar and wind electricity is likely to dramatically increase. However, because of their intermittent and variable production, power systems resilience and flexibility has to increase accordingly to assure the security of supply. Within this context, dispatchable capacity and energy storage systems acting on both short and long terms, will play a pivotal role. The COMESE code is applied to assess the affordability and reliability of alternative carbon-free Italian power system configurations. The 100% renewable generation option is compared to nuclear scenarios where a bold base-load generation is provided by nuclear fusion power plants. To manage the excess energy from renewables, the deployment of a power-to-hydrogen strategy is also investigated, besides the conventional storage through electrochemical devices. Also, the viability of a "fusion-to-hydrogen" strategy is assessed. The system cost of electricity of any least-cost 100% power systems configuration exceeds that of the corresponding alternative nuclear scenario. If energy curtailment is allowed, converting a portion of the excess energy into H2 for short and medium term storage is more affordable than storing the whole surplus generation. Finally, the system cost of electricity is lower if fusion energy is converted into electricity rather than hydrogen for long-term storage.