Brazil aiming to develop national microreactor

Wednesday, 19 March 2025

The vision is for the microreactor to fit within a 40-foot container and be operated remotely for more than 10 years without any need for refuelling. Suggested uses including providing reliable power to remote towns, to hospitals and factories and reducing dependency on diesel generators. Various universities and the Brazilian Navy and Amazônia Azul Defense Technologies are also involved in the project.

The National Nuclear Energy Commission (CNEN) says its Institute of Energy and Nuclear Research (IPEN) will be responsible for the research and development of essential materials for the microreactor, and its Institute of Nuclear Engineering (IEN) will be in charge of assembling a subcritical unit, to demonstrate the viability but without a self-sustaining chain reaction.

Professor João Moreira, from UFABC university and technical coordinator of the project, said: "There is still no microreactor operating in the world with established technology. We are developing something original, based on our technical and industrial competence, taking advantage of the experience of the Navy's nuclear programme, IPEN and IEN. The knowledge will be produced here, with national inputs, so that Brazil has autonomy and competitiveness in this strategic sector."

IPEN's work will focus on the study of different moderators, CNEN said, including beryllium oxide and control rod material, boron carbide.

IEN will be resuming research which began in the 1970s with the development of a subcritical unit. According to an article published by CNEN outlining the microreactor plans, the challenge for IEN "will be to test the behaviour of neutrons inside the reactor and other aspects of reactor physics. Through experiments, the institute will seek to prove whether the theoretical calculations on the functioning of reduced nuclei correspond to expectations. In addition, IEN will contribute to the instrumentation, an area in which it has vast experience. With the updating of the calculations and the manufacture of fuels by INB, the next step will be to conduct feasibility tests".

Among the project challenges will be the manufacture of the critical components, the development of the safety and control system, instrumentation and remote monitoring. The heat pipes "which remove heat and thermally stabilise the reactor, will require innovative engineering solutions", CNEN says. 

The commission said: "The project is currently at the TRL 3 technological readiness level, which corresponds to the mathematical modeling and preliminary studies phase. The goal is to advance to TRL 6, the level at which the technology is demonstrated in a relevant environment, closer to practical application."

There are various microreactor projects at different stages of development around the world. While small modular reactors are generally seen as including reactors up to 300 MW, microreactors are said by the International Atomic Energy Agency to be those designed for up to about 20 MW, with container-based ones seen as especially having the ability to be transported to a wide range of potential locations, including isolated areas.