Hydrogen Combustion Engines: New Paradigm/Old Parts

As the hydrogen economy adapts to myriad crosscurrents, products are coming to the fore that lower barriers to adoption but may entail efficiency and/or emissions tradeoffs. The hydrogen combustion engine (“HCE”) is one example. HCEs are less efficient than fuel cells and produce some NOx emissions (but can qualify as Zero Emissions Vehicles under EU rules given those emissions are typically very small). However, these engines can be lighter and more durable than fuel cells, have lower hydrogen purity thresholds and still produce no carbon emissions. Importantly, relative to implementing fuel cells, trucks, tractors, cranes, excavators etc. running on HCEs require less re-design, fewer changes to supply chains and are better able to maintain economies of scale. MAN Truck and Bus, for example, says 80% of parts in its HCE are the same as in its diesel engines.

Some recent developments in the commercialization of HCEs include:

>In January, after €100 million in product development expenses, JCB announced its HCE had been certified for commercial sale and use in eleven European countries including Great Britain, Germany, France and Spain. With its European certification process likely to reach a conclusion soon, engine sales are expected to begin this year.

>Also in January, Cummins unveiled the hydrogen version of its HELM platform (Higher Efficiency, Lower Emissions, Multiple Fuels) L10 engine engineered to meet upcoming BSVII and Euro 7 standards as well as a turbo charger for HCEs optimized to reduce NOx.

>In November, MAN Truck and Bus awarded a contract to MAHLE for certain components to be used in serial production of its HCE engine. MAN says it will distribute 200 HCE trucks to fleet customers in 2025 for testing.

>In addition, Daimler Truck unveiled two HCE prototypes last July (a truck and a tractor) after a year of successful testing. Volvo Trucks said it will begin customer tests of HCE trucks in 2026 and Bosch is also expected to launch an HCE in the coming months. Hyundai and Toyota are among others working to commercialize HCEs.