We model the optimal hydrogen and electricity production and storage mix for France by 2050. We provide a central scenario and study its sensitivity to the cost of electrolyzers, the hydrogen demand and the renewable energy deployment potential. The share of electrolysis vs. methane reforming with CO 2 capture and storage in hydrogen production is sensitive to the cost of electrolyzers, with the former providing around 60% in the central scenario. However, the system cost and hydrogen and electricity production costs are much less sensitive to these scenarios, thanks to the wide nearoptimal feasible space of the solutions. The electricity production mix is almost fully renewable in the central scenario, while nuclear has a significant role only if the wind & solar potential limits their deployment, or if blue hydrogen is not authorized.