Heavy-duty transport is one of the most challenging sectors to decarbonize, and hydrogen internal combustion engines have emerged as a highly practical solution capable of addressing many of the operational, financial and logistical constraints faced by long-haul truck fleets and large public transit operators. Heavy-duty trucks, city buses, regional coaches, construction haulers and specialized industrial vehicles require high power output, long distance capability, quick refueling and robust performance in all types of environmental conditions. Battery-electric technology, while effective for short routes and lighter applications, faces fundamental barriers such as limited range, long charging times, significant payload penalties and high battery costs. Fuel cell vehicles offer cleaner operation with greater efficiency, but their systems are complex and expensive, and they remain sensitive to dust, vibration and temperature extremes. For these reasons, hydrogen internal combustion engines have begun to capture increasing attention from global fleet operators seeking realistic near-term solutions that maintain performance while reducing emissions.
Heavy-duty transport is built on decades of diesel-dominant infrastructure, engineering practices and service models. Fleet operators rely on engines that provide high torque at low RPM, stable output over long distances, reliability in remote areas and the ability to handle harsh duty cycles. Hydrogen internal combustion engines mirror diesel powertrains in architecture, behavior, and maintenance requirements, making the transition for operators familiar and strategically advantageous. The greatest appeal lies in the fact that hydrogen ICE technology leverages the existing engine manufacturing ecosystem. Components such as crankshafts, pistons, turbochargers, cooling systems and lubricating circuits remain largely similar, with modifications made to support hydrogen’s unique combustion characteristics. This allows manufacturers to adapt current diesel engines into hydrogen variants without needing to build entirely new production lines, thereby accelerating the availability of hydrogen-powered heavy vehicles.
Refueling time remains one of the strongest advantages hydrogen combustion offers the heavy-duty sector. Commercial trucking depends on tight schedules, strict delivery windows and consistent uptime. Charging large battery-electric trucks can require hours, even with high-powered chargers, and installing megawatt-scale charging infrastructure can be prohibitively expensive for many logistics companies. Hydrogen internal combustion trucks, by contrast, can be refueled in minutes, similar to diesel, enabling continuous operation and avoiding costly downtime. This is particularly valuable for long-haul trucking routes that span hundreds of kilometers daily, where quick refueling directly translates into increased productivity and reduced operational cost. Many fleet operators prefer hydrogen ICE vehicles precisely because they can integrate into existing refueling-based workflows instead of transitioning to charging-based systems.
Another major benefit of hydrogen combustion engines in heavy-duty applications is performance consistency. Hydrogen’s high flame speed ensures rapid and complete combustion, producing strong torque output that is essential for hauling heavy loads up steep grades or maintaining speed on long highways. With the support of advanced turbocharging and direct injection technologies, hydrogen engines can match diesel engines in power and torque. Moreover, hydrogen ICEs handle cold weather better than battery-electric systems, which tend to lose range and efficiency in low temperatures. Hydrogen engines also perform reliably in extreme heat, high dust environments, and industrial territories such as mines, ports and construction sites where vibrations, debris and rapidly shifting duty cycles pose challenges for fuel cells and batteries.
Maintenance and operational familiarity are equally important factors driving adoption. Diesel mechanics can be retrained relatively quickly to service hydrogen combustion engines because the underlying mechanical layout is largely unchanged. Spare parts availability remains high due to shared components across engine platforms. In contrast, battery-electric trucks require specialized electrical technicians, and fuel cell vehicles require entirely different training and handling procedures. Fleet operators appreciate that hydrogen ICE technology reduces the learning curve, keeps service costs predictable and avoids the need for major retraining investments. Hydrogen engines also avoid the soot buildup and particulate emissions associated with diesel, potentially reducing downtime associated with maintaining exhaust aftertreatment systems.
