EV owners tend to spend more time charging in cold weather, according to a new data analysis from FLO, a Canadian electric vehicle charging company and General Motors partner. According to the analysis, electric vehicle drivers are spending longer to charge and taking on more energy when the temperature dips, with a correlation found for both level 2 and DC public fast charging stations. The analysis suggests a few possible explanations behind the data.
The analysis was based on data collected from electric vehicle chargers around the Greater Montreal area, which was selected for its high density of charging stations and reliably cold weather during the winter months. The analysis looked at 2,230 public charging stations operated over the entirety of the 2023 calendar year, and categorized stations based on the average temperature in Montreal. The study also excluded a few outlier days during which temperatures were either excessively high or excessively low.
The study found a direct correlation between lower ambient temperatures and extended electric vehicle charging times. This correlation applied to both level 2 and DC quick-charging stations. Days with temperatures of 23 degrees Fahrenheit (-5 degrees C) and below showed the average charge time extended by 16 percent, or 25 minutes, compared to days with temperatures above 50 degrees Fahrenheit (10 degrees C). Additionally, EV energy consumption increased an average of 17 percent, or 2.7 kWH, in colder temperatures.
FLO suggests a few possible explanations for the correlation between colder temperatures and longer EV charging time / greater EV energy consumption. Among these is lower vehicle efficiency in colder weather, with the U.S. DOE noting that all vehicles are less fuel-efficient in cold weather. Another possible explanation is deferred charging, with some electric vehicle owners preferring to avoid public charging until absolutely necessary. Finally, the study suggests that while the rate of charge may be slower in colder weather, some vehicles may take on more energy more quickly if they start from a lower rate of initial charge, thus increasing the amount of energy transferred.
The study suggests that electric vehicle owners use the battery pre-conditioning feature, if available, and plan trips ahead of time with cold weather considerations in mind.