Statistical Characterization of Public AC EV Chargers in the U.K.

Abstract

In recent years, the public AC electric vehicle (EV) charging network in the United Kingdom (UK) has experienced significant growth, more than doubling in size. However, there remains a significant lack of information regarding usage patterns, which hampers decision-making for future infrastructure planning. This study addresses this gap by presenting a statistical analysis based on data from nearly twelve thousand EV charging sessions. The data was collected from 595 AC charging sockets, with 85% operating at 7 kW and the remaining 15% at 22 kW, throughout the UK between April 2022 and July 2022. The analysis focuses on key factors that define the primary characteristics of the current public EV charging ecosystem, including utilisation rates, arrival-departure times, sojourn durations, energy transfer, and overstay durations. Several important observations are made, such as the variability in utilisation rates, factors influencing overstay periods, and peak demand periods. With two case studies, the potential role of smart charging in leveraging EV flexibility is shown by lowering and shifting the peak EV loads. The findings of this study have significant implications for the planning and efficient allocation of investments to expand the charging infrastructure. By gaining a better understanding of the current charging ecosystem, informed decisions can be made to optimise the usage and expansion of EV charging facilities.

Keywords

• Electric vehicles
• AC charging
• statistical analysis
• smart charging
• overstay