Energy management of hydrogen hybrid electric vehicles — A potential analysis

The hydrogen combustion engine (H2ICE) is known to be able to burn H2, producing no CO2 emissions and extremely low engine-out NOxeo emissions. In this work, the potential to reduce the NOxeo emissions through the implementation of electric hybridization of an H2ICE-equipped passenger car (H2-HEV), combined with a dedicated energy management system (EMS) is discussed. Achieving a low H2 consumption and low NOxeo emissions are conflicting objectives, the trade-off of which depends on the EMS and can be represented as a Pareto front. The dynamic programming algorithm is used to calculate the Pareto-optimal EMS calibrations for various driving missions. Through the utilization of a dedicated energy management calibration, H2-HEVs exhibit the potential to decrease the NOxeo emissions by more than 90%, while, decreasing the H2 consumption by over 16%, compared to a comparable non-hybridized H2-vehicle. The present paper represents the initial potential analysis, suggesting that H2-HEVs are a viable option towards a CO2-free mobility with extremely low NOxeo emissions.