Emission mitigation potential from coordinated charging schemes for future private electric vehicles

Plug-in electric vehicles (EVs) are expected to synergize with low or even zero-carbon electricity towards a deep mitigation of greenhouse gas (GHG) emission and ultimately carbon neutrality. These benefits are only obtainable when EV charging maximizes the consumption of electricity generated from renewable energy sources. However, the current mismatch between renewable energy output and EV charging demand poses a substantial challenge. Rescheduling charging events, namely charging coordination, has the potential to integrate renewable electricity and tap into higher GHG emission reductions. In this study, with Beijing as the research domain, we develop a charging demand model informed by real-world usage data generated by a massive fleet of private cars, and evaluate the comprehensive impacts of various charging coordination schemes in the future with higher adoption rates of both private EVs and renewable power sources. The research finds that strategies aiming at maximizing renewable power consumption, netload valley filling, and charging cost minimization have similar climate benefits, which can reduce well-to-wheels GHG emissions by approximately 20%, cut charging cost by half, and erase 95% of the need for newly installed generation capacity compared to the benchmark scenario without coordinated charging. On the other hand, conventional charging strategies, such as the simple demand-valley-filling strategy, would increase GHG emissions. The study indicates that substantial benefits can be synergistically achieved between power and transport systems towards improved grid stability, lower fuel cost, and greater emission mitigation by leveraging EV charging flexibility at the end-user side (i.e., charging facility). Furthermore, the potential need for sophisticated charging coordination with multiple optimization objectives is brought to attention.