Hydrogen Engine with 50 % BTE – Benefits of High-Pressure Direct Injection

On February 14th, 2023, European Union published an updated roadmap for CO2 reduction for commercial vehicles, associated with the “Green Deal” and Europe’s striving for carbon neutrality in 2050. Starting with the year 2030 significantly more stringent targets will be in place on the one hand side. On the other hand, the boundary conditions for Hydrogen internal combustion engines to be base powertrain for Zero-CO2-Emission-Vehicles (ZEV) were re-considered. Based on this proposal a commercial vehicle with a combustion engine emitting less than 5 gCO2/t-km (recent draft foresees 1 gCO2/t-km) brings equal benefits to the targeted CO2-fleet emission reduction as a battery electric or fuel cell electric truck.
Hydrogen as a fuel in an internal combustion engine for commercial applications allows either spark ignited lean burn or high-pressure direct injection concepts. Late cycle direct injection offers benefits in terms of power density, transient response as well as high efficiency. Fuel efficiency is a major contributor to optimize total cost of ownership for heavy duty vehicles, therefore high-pressure direct injection is an enabler to achieve carbon neutrality with highest efficiency for high load operation profiles combined with the robustness needed for commercial vehicle applications.
In this presentation, different ignition promoters, their influence on the combustion and on pollutant formation will be investigated. Additionally, the required aftertreatment systems for future emission legislation fulfilment will be discussed.