A recent comprehensive review by the Stockholm Environment Institute (SEI) has found that electric vehicle (EV) chargers globally are significantly underutilized, with each charger capable of supporting up to 135 vehicles — far exceeding the current average of 11 EVs per charger.
The extensive literature review, published in Energy Strategy Reviews, analyzed diverse studies on charging demand and concluded that large discrepancies between mean and median EV-to-charger ratios reflect varying assumptions and charger configurations across different regions and markets.
“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.
The report found that while the mean estimated demand stands at 135 EVs per charger, the median is much lower at 23, with real-world data averaging just 11 vehicles per charger, primarily focusing on public charging infrastructure.
“The median value could be seen as more representative of current markets with front-runner countries such as Norway and Sweden already exceeding it, while mean values that include outlier studies of larger EV fleets can be more helpful to understand future market needs,” Xylia added.
The study emphasized the need for balance in charger deployment: an excessively high EV-to-charger ratio risks long wait times at charging stations, while too low a ratio indicates underused infrastructure that may not be economically sustainable.
The review also underscored that there is no universal EV-to-charger ratio applicable worldwide. Instead, demand varies according to factors such as charging power, battery capacity, and user charging behavior, which are often not explicitly accounted for in existing studies.
Key recommendations from the study include the adoption of clear definitions for charger types — including “public” vs. “private” and “slow,” “fast,” and “super-fast” chargers — to facilitate meaningful data comparison and guide rollout strategies. The authors also propose incorporating metrics combining time and distance to better reflect actual user experience rather than relying solely on EVs per charger.
The research pointed out a geographic imbalance in existing data, noting that Europe and North America dominate charging infrastructure studies relative to their population sizes, while regions such as Asia, Africa, and Latin America are underrepresented. The study called for more research focused on these areas to ensure equitable development of EV infrastructure.
Additionally, the review highlighted the growing importance of private and semi-public charging and noted that several transport segments, including light-duty commercial vehicles, micromobility options, autonomous vehicles, and car-sharing services, are currently underexamined.
For heavy-duty vehicles, available data suggest one public charger per five electric buses and one per 14 trucks, although evidence on trucks remains limited due to their more recent market entry.