In September 2023, RAEB signed the Cooperation agreement with Dual Fluid Energy Inc. a Canadian-German nuclear technology company, to collaborate on the development of the Critical Demonstration Experiment (CDE) in Rwanda. The CDE is the functional prototype for the commercial DF300 reactor, a small modular reactor (SMR) design developed by Dual Fluid Energy Inc. which uses a unique "dual fluid" concept, meaning it has two separate fluid loops: one for the fuel and one for the coolant.

The goal of the experiment is to study in detail the behavior of a low-power Dual Fluid core in an experimental setup. The technology under experimentation is expected to provide cheap, safe and abundant energy to Rwanda and other countries.

The CDE setup is a minimal critical configuration (core diameter ≈60 cm) running for a limited time (at most 2 years) and demonstrating the Dual Fluid principle.

The CDE experimental hall with the CDE core vessel and part of the bio shield

The CDE underwent 10 years of extensive groundwork to achieve three Technological Readiness Levels (TRL 1, TRL 2 and TRL 3). These levels include studies of basic material properties and principles (TRL 1), moving ideas from basic to application (TRL 2) and analytical studies and laboratory-scale studies designed to physically validate predictions of separate elements of the Dual Fluid technology (TRL 3). The next level (TRL 4) to be conducted in Rwanda will ensure the demonstration and component tests of the Dual Fluid principle under the CDE setup.    

This Cooperation Agreement highlights the spirit of Rwanda to remain a proof – of – concept destination as a strategy to accelerate integration of innovative technologies and build a knowledge-based economy. 

Status of the CDE project 

The formal Initial Safety Assessment Report (ISAR) review process started in February 2025.  A preliminary complex engineering site survey report has been commissioned by RAEB, executed by expert companies, and delivered with positive result [in April 2024], i.e. the site is suitable for nuclear installations. The site license for Dual Fluid is expected to be one of the next steps. 

From 25-29 March 2024, at the invitation of RAEB, IAEA conducted in Kigali an Expert Mission on Safety Analysis and Design Safety Features of the CDE Project. RAEB and Dual Fluid are very grateful for the important support of internationally recognized experts in implementing international licensing norms. 

Group photo with IAEA Experts during the CDE mission in Kigali

The Technical Design and Safety Report (TDSR) is available and will soon be submitted to the Regulatory Authority (RURA) for review. A design approval can be expected soon. For more on the Dual Fluid technology: https://dual-fluid.com/