When Dr. Robert Cox pulls in his Charlotte, N.C., driveway, he plugs in his Chevrolet Volt. It’s not surprising. Research shows 80% of electric vehicle (EV) charging happens at home.
“One you drive an EV,” Cox said, “you realize that this overnight charging thing is a pretty big deal.”
But one in three U.S. households can’t just install a charger at home; take renters, for example, or people who park on the street. They’re what the industry calls “garage orphans,” and charging for their EVs is limited.
So Duke Energy and the Energy Production & Infrastructure Center (EPIC) at the University of North Carolina at Charlotte teamed up to create a potential solution in PoleVolt, an EV charger that mounts on a light pole with overhead power.
“It’s a location where you already have power,” said Cox, associate director EPIC, “and people parking in a curbside environment. Why not couple those things together?”
By using existing infrastructure, PoleVolt is easier and less expensive to install on a public street than a traditional EV charger. That gives it potential to help close the gap on an inequity that Cox said transcends income level.
“High-income earners who live in trendy uptown neighborhoods,” he said, “may lack access simply because of their housing choice. So, this garage orphans issue that we’re solving is not necessarily about socioeconomic status. Equity, in this case, is broad.”
Lack of charging has dissuaded a lot of people from ditching their gas-powered vehicles, a major contributor of air pollution, said Jamie Cleveland, a senior solutions developer in Duke Energy’s Community Customer Innovation group.
“Access to home charging is one of the most influential factors determining whether a driver will go electric,” Cleveland said. “We have to solve this problem if we want to grow EV adoption and, ultimately, decarbonize transportation.”
With a U.S. Department of Energy grant and support from Duke Energy, which owns the infrastructure, UNC Charlotte engineering students Alex Miller, Grady Harwood and Phillip Harmon brought their design to life, thanks, in large part, to Cleveland and Bruce Hoban, technology development manager, who helped create and test a prototype.
“We found a great set of partners in Jamie and Bruce,” Cox said of an idea they’d dreamed up years ago during a chat among colleagues at both companies.
Harmon designed a mobile site that starts and monitors a charging session, while product development continued at Duke Energy’s Emerging Technology Office (ETO), west of Charlotte.
With a bright LCD screen, video tutorials walk first-time users through the charging process, and EV drivers get visual feedback when it’s plugged in correctly – features made possible by a local intelligence module designed by the ETO’s Steve Hinkel.
Its heavy-duty cable also retracts between sessions, so people are less likely to cut or trip on it.
“These things may sound simple,” Cleveland said, “but we know from experience that poor experiences with public chargers often come back to one of these two things: not being certain if their vehicle is charging or locating a charger only to realize it’s broken. So, these design elements provide a lot of value.”
To minimize installation costs, the Outdoor Lighting Standards group designed brackets that simplified how the charging station is mounted to a Duke Energy light pole. For customers, this translates to lower attachment fees.
The City of Charlotte and Centralina Regional Council joined the public-private partnership in 2022, when the first level 2 charger was installed in Washington Heights, a neighborhood a few miles from the city center.
“I think it’s incredible,” Harmon said, “that in three years or so, we’ve managed to roll out a finished product to the public. It’s really cool to have had that experience before I even graduated.”
Duke Energy and EPIC continued to innovate into 2023, when a second PoleVolt was installed in Charlotte’s Belmont neighborhood, just outside of Uptown.
The charging station has an air quality sensor that measures pollution, an LED light that brightens as a vehicle approaches the parking space and a camera system for security, as well as an extended sidewalk and unloading area along the curb for people with disabilities.
It’s also faster, Cleveland said of its high-power built-in level 2 charger that is 40 amps in output compared to the 24-amp charger in Washington Heights. It can charge most electric vehicles from a 10% state of charge to full within seven to 10 hours.
As part of its agreement with the City of Charlotte, Duke Energy will operate the chargers through 2024. During that time, EV drivers can use the chargers at no cost.
Cleveland’s hope, though, is that Charlotte is just the beginning. He’d like to see PoleVolt become a standard part of kits that other cities could use for their own curbside chargers.
“We’ll need more funding to make this scalable,” he said, “but cities in Duke Energy service areas have already reached out with an interest in what we’ve created here. So the future looks bright.”