Experts at the Southwest Research Institute (SwRI) have successfully developed a hydrogen engine to decarbonise heavy-duty, long-haul trucking.
The Hydrogen Internal Combustion Engine (H2-ICE) produces ultra-low NOx and CO2 emissions while simultaneously producing enough torque and power for trucking applications.
Developed under the H2-ICE consortium, the hydrogen engine has been shown to power a hydrogen-fuelled Class-8 demonstration vehicle successfully.
The innovation could prove instrumental in significantly curbing the sizeable emissions generated in the trucking industry.
Hydrogen engine development
To manufacture the H2-ICE, the consortium combined a vast array of experts, including engine and truck manufacturers, fuels and lubricants providers, and Tier-I suppliers.
The focus of the project was to demonstrate the potential of hydrogen-powered vehicles to complement other zero-emission vehicles on the road toward decarbonisation.
The researchers set a target for the engine to achieve the California Air Resource Board’s (CARB) Ultra-Low NOx designation of 0.02 g/hp-hr (grams per horsepower-hour).
Ryan Williams, an SwRI Powertrain Engineering Division manager, and the H2-ICE consortium’s program manager, explained: “We wanted the programme to align with the Environmental Protection Agency’s Phase-3 greenhouse gas policy, so we knew our timeline was ambitious.
“It took incredible planning by the integration teams to ensure that the build proceeded smoothly.”
To achieve this, they advanced a truck engine provided by consortium member Cummins to run on port-injected hydrogen using components provided by other members.
From custom-built parts and prototype components to specially formulated lubricants, this has truly been an industry-wide effort,” said Williams.
“We could never have completed the demonstration vehicle in the short time that we did without the support and collaboration of the consortium.”
Exceptional performance to decarbonise long-haul trucking
The H2-ICE vehicle offers a compelling zero-GHG solution for the challenging long-haul trucking market.
Its 370-horsepower engine, producing 2,025 Newton-meters of torque, is ideal for heavy-duty applications with an efficiency above 40%, peaking at 43%. Exhaust emissions are minimal, at about 1.5 grams of CO₂ per horsepower-hour.
Additionally, SwRI leveraged previous low-NOx project experience to create a novel after-treatment system for the hydrogen exhaust.
This system, combined with the low emissions of the hydrogen engine, reduces NOx levels to 0.008 g/hp-hr with aged catalysts, far below the 2027 EPA limit of 0.035 g/hp-hr, marking an industry first.
By producing ultra-low NOx and CO2 emissions while maintaining high power and efficiency, the hydrogen engine demonstrates the potential to reduce the sizeable emissions associated with long-haul trucking significantly.
