Analysis of an integrated thermal management system with a heat-pump in a fuel cell vehicle

Abstract

Fuel cell vehicles (FCVs) are becoming increasingly popular because they are both environmentally friendly and energy efficient. However, because no waste heat from the internal combustion engine can be used, the additional electricity needed to heat the cabin in cold weather increases the energy consumption substantially. This also lowers both the fuel economics and driving range. The required additional heating is typically done with a positive temperature coefficient (PTC) electric heater. To overcome the associated performance problem, a novel vehicle-integrated thermal management system (VTMS) with a heat-pump system is developed and investigated in this study. Using a simulation, the performance of the VTMS is investigated with respect to cooling performance, heating performance, and heating energy consumption for several different heat sources. For four different driving cycles, the equivalent hydrogen consumption (EHC) is highest when the PTC heater is used. The heat-pump system, which uses waste heat generated by a proton exchange membrane fuel cell, shows the lowest EHC. The results reveal that the use of a heat-pump heating system with waste heat can reduce hydrogen consumption by ∼14.6%, 6.5%, 16.9%, and 16.7% compared to PTC heating. Furthermore, the driving ranges increased by 17.2, 6.8, 20.3, and 12.6 km per 100 km, respectively. The VTMS, thanks to its ability to reduce energy consumption effectively, makes it possible to improve the thermal comfort in the vehicle cabin, which is especially useful for the commercialization of FCVs.