Stellaria is a French nuclear startup co-founded by CEA and Schneider Electric developing the Stellarium — a fourth-generation fast-neutron molten salt reactor that regenerates its fuel for over 20 years of self-sufficient operation. The company raised €23 million in 2025 and received €10 million in France 2030 programme funding. In February 2026 Stellaria submitted an application for its Alvin prototype and signed a power pre-order with Equinix — making it the first French SMR startup to secure a hyperscaler data centre customer.
At One Ventures, Supernova Invest, CEA Investissements, Schneider Electric