Environmental benefits of combined electro-thermo-chemical technology over battery-electric powertrains

Abstract

Electric vehicles are being promoted worldwide in an attempt to mitigate greenhouse gas emissions and improve air-quality in cities. Yet, alternative propulsion systems could allow meeting climate change and air-quality policy goals while not raising other environmental burdens. This study offers a glimpse into the mobility solutions aside from traditional battery-electric vehicles (BEVs). A feasibility study of the novel combined electro-thermo-chemical (CETC) propulsion technology composed of a fuel-cell (FC), an internal-combustion engine (ICE) and thermochemical recuperation (TCR) of waste heat is performed based on a life-cycle assessment. A comprehensive comparison between the proposed technology and the BEV is conducted across multiple categories of environmental impacts from the stage of manufacturing, through vehicle use and vehicle end-of-life. Our findings showed for the first time that a technology comprising an internal combustion engine can assure a better environmental performance compared to BEV. Moreover, we demonstrate that the climate-change benefits of the suggested CETC technology over BEV are more pronounced when the share of renewable energy use increases. The study results show that the new CETC technology outperforms the battery electric propulsion for the majority of environmental impacts, including climate-change, air-pollution, human-health and ecological impacts by up to 22%, 62%, 60% and 43%, respectively. It is found that the environmental advantages of the CETC technology over the BEV stem mainly from the vehicle manufacturing stage, affected by the BEV's higher weight and resource-intensive production. These encouraging findings call for further examination and research into BEV alternatives, such as the discussed hybrid CETC powertrain. The latter has promising prospects for future implementation in both mobile and stationary applications.