Technology
Discover how the Otrera reactor is redefining the future of energy with cutting-edge technology and unmatched efficiency.
Making Fast Neutron Reactors (FNRs) Competitive
When the fast neutron reactor (FNR) sector was first developed, its main objective was the production of plutonium.
This led to specific design choices for the reactor core and boiler systems, resulting in oversized components. The resulting complexity increased building sizes and led to construction costs significantly higher than for conventional light-water reactors (LWRs).
This original design brief contributed to the widespread belief that sodium-cooled FNRs would cost 30 to 50% more than LWRs. Yet energy needs have changed, and the historical deserve to be reconsidered.
At Otrera, this is exactly what we are doing: rethinking core design decisions to meet today’s challenges with a clear ambition—make fast reactors simple, safe, and cost-competitive.
Delivering Technology for the Future
The OTRERA concept is based on a compact, modular loop-type architecture, drawing inspiration from proven LWR principles. It features three alternating reactor vessels: two in operation and one in cooling. This configuration allows for in-vessel fuel cooling, eliminating the need for separate storage pools—a major cost-saving innovation.
The project is designed to reduce or even eliminate the traditional limitations of sodium technology. Our solutions allow us to:
- Significantly reduce the number of severe accident scenarios,
- Simplify the reactor’s overall architecture,
- Shrink the size of components and supporting infrastructure.
All these choices serve a single purpose: lowering capital and operating costs to make this technology competitive with water-cooled reactors.
Three Key Differentiators of the Otrera Reactor
An Innovative, Modular Architecture
Our architecture, the result of two years of intensive design work, introduces innovations such as system simplification and a fourth containment barrier in addition to the three found in today’s nuclear reactor fleets.
OTRERA’s modular design relies on standardized components, enabling a range of reactors from 30 to 450 MWe while significantly cutting costs and qualification timelines.
Factory-prefabricated Components with a High Level of Maturity
The components planned for the OTRERA reactor are based on proven expertise from RNR sector components. Their limited size, due to the OTRERA reactor’s compactness, allows for factory prefabrication and testing operations to reduce on-site assembly and testing times. Furthermore, the reactor’s design enables a modular approach to offer a wide range of power options for electrical and/or thermal energy production.
For example, the sodium/gas heat exchanger and the electromagnetic pump are central to the modularity of the OTRERA reactor range, which boasts a thermal power of 50 MWth. These two components have reached pre-industrial maturity levels (TRL 5/TRL 6), facilitating accelerated market entry by 2032.
Reinforced Safety, Built Into the Desig
The main safety design choices to enhance operational security include:
- Design-based elimination of sodium-water and sodium-air reactions, notably through the use of a sodium-gas heat exchanger,
- Elimination of severe core degradation scenarios thanks to open fuel assemblies,
- No pressurization in the primary loop,
- Use of redundant and diversified passive systems for core residual heat removal,
- Inclusion of four containment barriers,
- A semi-buried reactor building, offering high levels of physical protection and resilience to external threats.
Small Modular Reactors (SMRs): An Energy Revolution
Small Modular Reactors represent a breakthrough in nuclear power. More compact and flexible than traditional large-scale plants, SMRs provide an innovative response to growing energy needs while minimizing environmental impact. Their modular design allows for rapid deployment and regional adaptation, making nuclear energy more accessible and sustainable. Explore how SMRs are reshaping the global energy landscape and contributing to a greener future.
Together, Let’s Redefine Nuclear Energy!
At Otrera, we believe in the importance of innovation to shape a sustainable energy future. We invite you to learn more about the exciting advancements in nuclear reactors, particularly sodium-cooled fast reactors and small modular reactors. Engage in the conversation and discover how you can contribute to redefining nuclear energy. Together, let’s build a cleaner and safer energy future.