Hydrogen Combustion Engine

A hydrogen combustion engine is a reciprocating marine engine that burns hydrogen in the cylinder rather than feeding a fuel cell, run either as a pure hydrogen engine or as a dual-fuel engine blending hydrogen with diesel or natural gas. Combustion is carbon-free at the tank-to-wake stage, so the only in-cylinder greenhouse emission is the NOx from high flame temperature, managed by lean operation, water injection, or SCR. The engineering problems are pre-ignition, knock, and backfire from hydrogen’s wide flammability range and low ignition energy. MAN Energy Solutions and Wartsila are developing four-stroke hydrogen engines, with Wartsila reporting pure-hydrogen test running.