Doosan Infracore has announced the successful completion of initial testing for its hydrogen internal combustion engine (H2-ICE) designed for large excavators operating in the quarry and mining sectors. While much of the industry's zero-emission focus has been on battery electric or hydrogen fuel cell technology, Doosan's approach retains the familiar architecture of a traditional diesel engine, swapping the fuel source for direct-injected hydrogen gas. This strategy offers a pragmatic transition path for heavy-duty applications where battery weight and extended recharging times are dealbreakers.
The primary engineering challenge with hydrogen combustion is controlling pre-ignition and minimizing nitrogen oxide (NOx) emissions. When hydrogen combusts at high temperatures in the presence of atmospheric nitrogen, it produces NOx. Doosan's engineering team tackled this by developing a lean-burn combustion strategy paired with a highly precise, high-pressure direct injection system. By injecting the hydrogen directly into the combustion chamber at pressures exceeding 300 bar during the compression stroke, and utilizing a micro-pilot diesel injection (less than 5% of total fuel) as an ignition source, the engine achieves a stable, clean burn that keeps cylinder temperatures below the NOx formation threshold.
Crucially, the H2-ICE platform bolts directly to existing transmission and hydraulic pump interfaces. This means OEMs do not have to redesign the entire chassis, counterweight, or cooling pack to accommodate the new power source. For quarry operators, this translates to immediate familiarity for maintenance technicians, as the engine block, crankshaft, and aftertreatment system remain largely identical to their diesel counterparts.
During a 2,000-hour durability test in a basalt quarry, the H2-ICE excavator matched the breakout force and hydraulic flow of the diesel equivalent while cutting operational carbon emissions by over 95%. The residual 5% is attributed to the micro-pilot diesel ignition. Doosan is now partnering with hydrogen infrastructure providers to develop on-site refueling solutions, aiming to make the H2-ICE excavator commercially viable for high-throughput aggregate operations by 2027.
