A new study out of Cornell University details the challenges of operating electric buses in the Tompkins County area, and strategies to address how those vehicles consume energy during freezing upstate winters.
Researchers tracked the energy consumption of seven electric buses in the Tompkins Consolidated Area Transit, or TCAT, fleet over two years. The transit service no longer runs those buses, citing issues with maintenance, parts shortages and the bankruptcy of Proterra, the company that sold the buses.
The study showed that cold weather significantly increased how much energy was used by the buses' batteries.
Dr. Max Zhang is an engineering professor and a senior author of the study. He said cold weather increases the energy needs of all vehicles, even those with internal combustion engines. However, he said the significant decrease in cold weather performance by the electric buses included in the study was surprising.
“We saw an almost 50% decrease in the energy efficiency of the vehicles,” Zhang told WSKG. “So I think that's, you know, obviously a little bit unexpected, right?”
Driving through urban areas also increased energy consumption in the winter. Frequent stops meant more open doors and cold air, which made heating the bus more energy-intensive.
However, Zhang said the problems outlined in the study don’t mean that all electric buses are a lost cause. Instead, providers need buses that are better equipped for the winter weather.
“As a community in the cold climate region, we should advocate for vehicles that are designed for this region.”
Zhang said that would require transit services to shop around for buses that can handle the cold.
“Not all electric buses are created equally,” he said. “I feel like some of the manufacturers have not thoroughly tested or evaluated their vehicles in our region or in similar regions with cold temperatures.”
Researchers also recommended adjusting the bus schedule, maintaining electric vehicles indoors, and charging the vehicle while the battery is still warm to combat cold weather inefficiencies.