Recently the European Union (EU) has declared ambitious targets for CO2 emission reduction in the heavy-duty vehicle segment. The published decarbonization strategy considers a reduction of CO2 emissions by 90% until the year 2040. Intermediate steps foresee a reduction percentage of 45% by 2030 and 65% by 2035. Recently these targets are increased further to 100% in 2040, 95% in 2035 and 65% in 2030.
Due to the need to develop CO2-emission free propulsion technologies also for the commercial vehicle sector the hydrogen internal combustion engine (H2-ICE) technology is getting increased attention in the automotive industry. Currently, various manufacturers around the world are looking into the development of H2-ICE based propulsion concepts.
The spark ignited H2 combustion process itself does produce almost no species/pollutants which are currently in scope of different emission regulations if a specifical air to fuel ratio is maintained. However, during transient operation, a drop in air to fuel ratio can lead to high levels of NOx formation requiring post-treatment technologies (SCR) to comply with current and upcoming regulations such as Euro 7 and Carb MY27.
In this article possible aftertreatment concepts for a H2-ICE are described for different legislation scenarios.
Additionally, R&D results of an actual H2-ICE equipped with an aftertreatment system configured specifically for the exhaust gas composition of a H2-ICE are discussed. The system was tested in representative testbed test protocols as for example the WHTC cold and hot. Legally regulated gaseous emission species and PN10 were measured upstream and downstream of the exhaust aftertreatment systems (EAS).
