Idealized analysis of relative values of bidirectional versus unidirectional electric vehicle charging in deeply decarbonized electricity systems

Michael O Dioha; Tyler H Ruggles; Sara Ashfaq; Ken Caldeira

doi:10.1016/j.isci.2022.104906

Idealized analysis of relative values of bidirectional versus unidirectional electric vehicle charging in deeply decarbonized electricity systems

iScience. 2022 Aug 11;25(9):104906. doi: 10.1016/j.isci.2022.104906. eCollection 2022 Sep 16.

Authors

Michael O Dioha¹, Tyler H Ruggles¹, Sara Ashfaq¹, Ken Caldeira^{1

2}

Affiliations

¹ Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USA.
² Breakthrough Energy, Kirkland, WA 98033, USA.

Abstract

We employed an idealized macro-energy system model to examine how the value of unidirectionally- and bidirectionally-charging electric vehicles (EVs) varies with EV penetration and mix of electricity generators. We find that EVs can help wind and solar-based electricity generation systems to be less costly by making better use of power that would otherwise be curtailed and, potentially, by giving electricity back to the grid at times of peak net load. At low levels of EV penetration, bidirectional EVs are valuable because they can provide electricity at times of main load peak. At today's low levels of EV penetration, bidirectional EVs stimulate investments in solar and wind generation and substantially reduce the need for grid-battery storage compared to unidirectional EVs. At high levels of EV penetration, generation capacity must be increased, and most peaks in main net load demand can be met by reductions in charging by unidirectional EVs.

Keywords: Energy management; Energy modeling; Energy policy; Energy resources; Energy systems.