A new study by the Stockholm Environment Institute (SEI) has found that electric vehicle (EV) chargers are significantly underutilized, with the average charger capable of serving up to 135 EVs, compared to the global average of just 11 vehicles per charger. The research, published in Energy Strategy Reviews, suggests that this disparity reflects widespread inefficiencies in current charging infrastructure deployment.
The literature review, described as the most comprehensive to date on EV charging demand estimates, highlights the gap between the mean and median number of EVs per charger—135 and 23 respectively. “Even though there is extensive research on charging infrastructure, there is no comprehensive mapping of charging demand estimations. Our review is the first of its kind, helping design more efficient charging deployment and informing new research on optimal charger placement,” said Maria Xylia, Senior Research Fellow at SEI.
Xylia noted that the median figure may better represent current leading EV markets such as Norway and Sweden, while higher mean values reflect outlier studies that anticipate larger EV fleets. “If the EV to charger ratio is too high then there is risk for queuing for charging at some locations, while a low ratio indicates we have underutilized infrastructure which is not economically viable in the long term, so there has to be a balance,” she added.
The study warns against one-size-fits-all approaches, noting that demand depends on factors such as charging power, vehicle battery capacity, and charging strategies. Key recommendations include refining EV fleet power demand indicators, standardizing definitions for charger types, and incorporating user experience metrics such as time and distance into planning.
Geographically, the current research is heavily weighted toward Europe and North America, with limited data from Asia, Africa and Latin America—regions with growing EV markets but underrepresented in global studies. The review also emphasizes the need to account for private, semi-public, and emerging vehicle segments, including commercial fleets, micromobility and autonomous vehicles.
For heavy-duty vehicles, the study found that public infrastructure typically includes one charger per five buses and one per 14 trucks, although data for electric trucks remains scarce due to their recent entry into the market.
SEI calls for more forward-looking strategies and inclusive research to guide public and private stakeholders in developing cost-effective and future-ready EV charging networks.
