Charging station status is inaccurate more than a quarter of the time, U.S. study says

More than a quarter of electric vehicle charging stations misreport their status, leaving drivers with inaccurate information as they try to figure out where they can charge their vehicles on the road.

Stations either appeared as out of service and were functional, appeared online but were offline or appeared to be in use when they were available 26 percent of the time in a study by ChargerHelp, a company that handles operations and maintenance for EV chargers.

Nearly 11 percent of stations appeared offline but were actually online, 1.9 percent appeared online but were offline, 3.6 percent misreported occupancy status as either busy or available, and roughly 10 percent had both software and physical cues indicating the station was online while failing to deliver a successful charge.

In general, the study found that chargers significantly misreport their uptime, or the amount of time that the charger is functional.

The findings demonstrate that station reliability is often an information problem. While charging stations may not be as widely available as drivers would like, neither the industry nor the consumer has accurate information about when and where chargers are operating.

People are saying, "'Everything is broken; nothing works,' but not really getting into the specifics of this being a software, data, interoperability problem," said Kameale Terry, CEO of ChargerHelp. "A solidified uptime calculation holds us accountable."

The company used its own data from site visits and work orders as well as data from the U.S. Department of Energy, electric utility filings and Paren, a data platform for EV charging that includes more than 9,700 stations. The University of California, Davis endorsed the study.

Charging availability and reliability have emerged as huge obstacles to wider EV adoption. Eighteen percent of public charging attempts failed during the fourth quarter of 2023, a slight improvement from the nine months prior, according to J.D. Power. Long wait times and lack of charger availability continue to impact drivers and those problems appear to be getting worse.

An April report by AlixPartners found that battery-electric vehicle owners were slightly more likely than the general respondent pool to express concern that there are not enough places to charge, meaning that charging angst is afflicting experienced EV drivers even worse than prospective buyers or skeptics.

There are many factors that can impact charger reliability.

The ChargerHelp study found that the condition of the payment system had a "significant, strong positive correlation" with the actual status of the charger. In other words, chargers with payment system issues were significantly more likely to accompany stations that were down.

Not only are credit card readers complex systems, they must interoperate with the chargers, themselves complex systems.

"Credit card readers have their own communication protocol and they also have their own back-end software, and they're also made by completely different companies than the folks who make the charging infrastructure," Terry said.

The ChargerHelp study recommended that network providers and station operators keep data accessible, that the industry coalesce around a way of calculating uptime accurately and that manufacturers keep the chargers coming using dedicated funding.

"The best way to fix charger reliability is to install many more chargers," said Gil Tal, the director of the Electric Vehicle Research Center at UC Davis. "We still need to fix the broken ones, but we need many more chargers — we have more chargers; we have more locations; we have more chargers in each location; we just have more redundancy."