Alchymiste project: work package 1 technical and economic modelling of hydrogen in support of insular electrical grids

Islands face unique challenges in their energy transition, including vulnerability to climate change impacts and heavy reliance on imported fossil fuels. With ambitious decarbonization and energy autonomy targets for 2030 and 2050, integrating intermittent renewable energy sources like solar and wind presents complexities due to production and demand balance, grid stability issues, and limited interconnections. This study, undertaken as part of the ALCHYMISTE project, investigates the large-scale potential of hydrogen to support insular electrical grids. A primary focus is placed on its technical feasibility and economic competitiveness as an electricity storage solution, along with the utilization of hydrogen in co-combustion with diesel or biodiesel within existing thermal power plants. Technical and economic modelling for Corsica's electrical grid projects for 2030 and 2040 demonstrates that hydrogen, produced from renewable energy surpluses, is instrumental in achieving higher than 90% renewable shares (up to +5%) and higher energy autonomy (up to +2%) by 2040. Hydrogen production facilities effectively manage excess solar energy and provide grid services, with production costs proving competitive against conventional fuels like bioliquids and approaching diesel's Levelized Cost of Electricity (LCOE). However, the current limitations of high-pressure gaseous hydrogen storage constrain its full potential for very large-scale applications. This research highlights hydrogen as a viable and essential component for island decarbonization, offering valuable insights for energy transitions on a broader continental scale.