Thermodynamics and energy usage of electric vehicles

• Published in: Energy conversion and management 2020-01, Vol.203, p.112246, Article 112246
• Main Author: Michaelides, Efstathios E.
• Format: Article
• Language: English
• Subjects: Alternative energy sources; Batteries; Carbon dioxide emissions; Charging; Electric power grids; Electric vehicles; Electricity; Electricity distribution; Energy consumption; Energy resources; Energy sources; Energy usage; Exergy; Greenhouse effect; Greenhouse gases; Incentives; Internal combustion engines; Motivation; Renewable energy sources; Transportation; Vehicle wheels
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2019.112246

•An exergetic analysis of road vehicles is performed.•Well-to-wheels efficiencies of electric and thermal-engine cars are calculated.•The greenhouse gas emissions of electric vehicles are determined.•The effects of electric cars on the electricity grid demand are discussed.•Charging by renewable energy sources is examined. The global number of electric vehicles is exponentially rising, due to strong marketing efforts and governmental incentives that significantly lower the price of new vehicles. This shift of consumers from internal combustion engine vehicles to electric vehicles is actually a shift from petroleum to the primary sources that generate electricity. The motivation for this paper is the holistic analysis of electric vehicles and the determination of their benefits and detriments. Starting with an exergetic assessment for all road vehicles, this paper determines the electricity needed for the propulsion of electric vehicles. When the heating and cooling requirements of the vehicle’s cabin are included, the range of the vehicles decreases significantly. The electricity requirements of the vehicles are abridged to primary energy sources using the concept of well-to-wheels efficiency. Based on the regional mix of electricity generation, the effect of the shift to electric vehicles on greenhouse gas emissions is determined. Because the charging of the batteries of electric vehicles requires significant power, it was concluded that the simultaneously charging of a number of vehicles will strain the capacity of the electricity grid. The paper also examines the effects of electric vehicles on the further utilization of renewable energy sources.