As part of the BrittanHy Day, held on 22 September, the French start-up EHM unveiled their famous 5-stroke hydrogen engine. The 265 kW (360 hp) unit is designed for coaches and trucks.

Founded in May 2022 in Châteaulin, Finistère, in the western part of Brittany, Efficient Hydrogen Motors (EHM) claims to have a disruptive innovation in the field of hydrogen internal combustion engines (H2 ICE). This engine was presented for the first time at the BrittanHy Day*.

The start-up is also using the event to announce that it will be integrating its engine into a Transdev coach.

This will be a world first. Converting such a vehicle to hydrogen has already been done (Iveco Crossway) with a fuel cell, but never with a hydrogen engine. Financed by ERDF**, this coach will be on the road in Morbihan (Brittany) in 2025. It will refuel at the hydrogen station in Vannes.

EHM took part in an overview of the hydrogen solutions developed in Brittany at the end of the day. It was an opportunity for the start-up to give more details about its engine. Note that it will also be on display a few days later at the Le Mans Hydrogène event, on 26 and 27 September.

EHM hydrogen engine: a team effort

Supported from the outset by the Brittany region and backed by local university research structures such as UBS, ESTACA and ENSTA, the project consists in developing a high-performance five-stroke engine powered by hydrogen.

First incubated by ENSTA Bretagne, then by ACCEL’AIR, which provide the team with premises and laboratories, the EHM team has developed its first 265 kW H2 ICE. The engine will now be put through its paces on the test bench in November.

*Organised by the Brittany region, the Côtes d’Armor Chamber of Commerce and Industry and Bretagne Développement Innovation.

**European Regional Development Fund

Do you want to learn more about hydrogen engines? Then our latest 2 articles on the subject should interest you. You can read them here and there. 

Article written by Laurent Meillaud and translated by Logan King