Redefining nuclear for a sustainable future

Designed to meet the needs of industries, urban heating networks, and regions in transition, Otrera reactors offer a concrete solution to the challenges of decarbonization, energy sovereignty, and reshoring production.

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50 years of French research and industrial expertise in fast neutron reactors to redefine nuclear energy

OTRERA is a French deeptech company that develops sodium-cooled fast modular reactors (SFRs), capable of co-generating competitive electricity and heat.

Founded in 2024 in Aix-en-Provence, the company now brings together over 30 employees. A laureate of the France 2030 program and certified Greentech Innovation, OTRERA is shaping the future of sustainable nuclear energy — both in France and internationally.

About Otrera

Together, we are building the energy of tomorrow

At Otrera, we believe that tomorrow’s nuclear energy must not only produce clean energy, but also multiply its potential and make it accessible at a reliable and controlled cost. From almost nothing, everything becomes possible: this is our promise of abundant, competitive, and sustainable energy for generations to come.

Frédéric Varaine
Founder – CEO, Otrera

At the heart of Otrera’s next-generation reactor

Compact and modular architecture

A simplified architecture with six 50 MWth modules, a vessel less than 3 meters, and standardized components, ready for large-scale industrial manufacturing. All deployable on an area of less than 5 ha.

Flexible, sustainable, and closed-cycle oriented

A high-performance, long-operating-cycle, next-generation core, compatible with both MOX fuels from currently unreprocessed and stored spent fuel assemblies, as well as with UO₂ HALEU, which is simpler to manufacture and intended for export.

Integrated safety and sustainable performance

Operating unpressurized, in an inert atmosphere, the reactor benefits from four containment barriers and passive safety systems. Designed to offer lasting resilience, it incorporates the requirements necessary for enhanced public acceptance, particularly when located in urban or industrial areas.

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A compact solution, where it is needed.

Reactors designed to meet the needs of regions and energy-intensive industries

The reactors developed by Otrera are aimed at public and private stakeholders committed to decarbonizing their energy production, securing their supply, or reindustrializing their regions. Thanks to their modular format, cogeneration capacity, and economic competitiveness, they meet the needs of multiple sectors.