Hydrogen bus fire in Belfort: initial findings point to electrical cause

“The fire was not related to hydrogen or its use.” This clarification comes from Yannick Monnier, Director of the Régie des transports du Territoire de Belfort, following the incident that destroyed seven hydrogen-powered buses at the Optymo depot in Danjoutin on January 2nd 2025.

In his interview with French media outlet Mobily-Cités, Monnier highlighted that initial analyses suggest the blaze was electrically generated, though the exact malfunction remains under investigation. Crucially, the vehicle at the center of the fire had been out of service since December 31, ruling out any thermal activity at the time of the incident.

Safety system and fuel cell bus fire

Monnier offered reassurance about the incident, underscoring the effectiveness of the hydrogen buses’ safety mechanisms. “All the safety systems on the hydrogen buses worked perfectly. The TPRD fuses on the tanks effectively evacuated the hydrogen, generating hissing noises that alerted local residents and mobilised the fire brigade,” he explained.

“The flares that fed the fire came from burning plastics and other materials, unrelated to the hydrogen flames, which were quickly dissipated by the safety devices.”

“This incident will not question Belfort’s hydrogen strategy,” Monnier added, reiterating the plan to power 50% of the bus fleet with hydrogen by 2025.