High-efficiency climate control systems with a heat and cold storage unit for electric vehicles

Abstract

Range reduction caused by climate control is a barrier to widespread adoption of electric vehicles (EV). Higher efficiency and lower energy consumption by the air conditioning system will mitigate this disadvantage, as power consumption inside electric vehicles is a very relevant issue. Moreover, several European Union directives prohibit the use of HFC 134a or any other fluorinated greenhouse gas with a Global Warming Potential (GWP) higher than 150 in new mobile air conditioning systems by January 2017. The Adoption of environmentally friendly refrigerants and minimizing the charge of refrigerant gas would be a viable option to endorse the EU directives. In this lecture, alternative climate control systems which profit from the advantages of thermochemical energy storage will be presented. In order to investigate the suitability of these systems for the high temperature fuel cell range extender vehicle (HTFCREX) developed by the DLR Institute of Vehicle Concepts, suitable climate control systems based on the use of hydrogen are developed, modeled and designed using the simulation environment Modelica/Dymola and the Air Conditioning Library. Based on simulation results, the alternative climate control systems are compared with regard to their efficiency, weight, volume and performance. These systems exhibit a reduction of 5 % to 22 % of electrical energy consumption depending on the system design in comparison to the reference HVAC.