What if metals could store and transport renewable energy?

On September 17, 2026, Zakarie Bruyr successfully defended his PhD, under the supervision of Professor Francesco Contino.

Storing and transporting renewable energy is a key challenge for the energy transition. Apart from e-fuels, such as hydrogen or ammonia, metal fuels represent simple and safe renewable energy carriers. Iron is abundant, cheap, safe, and burns in a combustion regime allowing for the collection of combustion products. Those iron oxides can subsequently be regenerated back to iron using renewable energy, creating a carbon-free closed cycle.

His thesis investigates the combustion process of iron particles, including the analysis of micro-explosions, the influence of impurities, as well as the role of this technology in a European energy system.

• The combustion process was first studied experimentally using a multi-scale approach including:
• a single-particle levitator located in CNRS Orléans allowing for particles stabilization and ignition, and
• multi-particle burners both in TU Eindhoven and in our lab (CREDEM) allowing for ignition analysis and production of combusted particles.
  A single-particle numerical model was also developed and validated using experimental data.

This research shows that metal fuels could play an important role in our future European energy mix. Moreover, this work also proves that working with impure powders is feasible and should receive more attention from the research community to finally design optimal impure powders burner.

During this PhD, funded by the FNRS, strong collaboration with the team of Fabien Halter in CNRS Orléans considerably improved the quality of the research and allowed for innovative experimental campaigns. 
Collaboration with the metal-fuels research team of TU Eindhoven also strongly helped him conduct his different numerical and experimental analyses.

Congratulations to Zakarie for this important achievement, and we wish him all the best for the next steps of his career!