Improving limiting factors for heat transfer from fuel cell electric vehicles to buildings using a multiphysical system model

This study investigates the suitability of fuel cell electric vehicles (FCEVs) as combined heat and power sources for buildings with conventional radiator heating systems. While previous work demonstrates high efficiencies for low-temperature heating, applicability at elevated supply temperatures remains unclear. Experiments with a modified passenger FCEV at supply temperatures of 40 and 50 °C show that heat transfer efficiency decreases by up to 57 %. A multiphysical simulation model identifies the vehicle-integrated heat exchanger and coolant mass flow rate as the dominant heat transfer limitations. Model-based parametric studies show that increasing the heat exchanger area and coolant flow enables heat transfer efficiencies above 99 %. The results indicate that the reduced performance at elevated temperatures arises from system design rather than fundamental thermodynamic constraints and support the technical feasibility of the concept to radiator-heated buildings.