By 2030, more than half of all new vehicle sales are expected to be all electric. But passenger vehicles only tell part of the story.
Manufacturers like Volvo, Ford, and Freightliner are already launching or developing electric heavy-duty trucks, a move that could make a major dent in carbon emissions. These vehicles account for only 5 percent of traffic but contribute 23 percent of all greenhouse gas emissions from transportation.
However, little attention has been paid to how and where these trucks will charge their batteries, and it’s no small problem. Because just-in-time delivery is essential to the national supply chain, truck charging stations must be robust, sustainable, and impervious to blackouts.
“It’s high time that we started thinking about how we are going to charge electric trucks,” said Robert Rosner, the William E. Wrather Distinguished Service Professor in astronomy and astrophysics and physics at the University of Chicago. “There’s a lot of information out there on how we are going to electrify transportation, but the very difficult parts like this have not been studied.”
Rosner and his colleagues –from both the University of Chicago and Argonne National Laboratory – set out to find out just how much it would cost to set up a charging infrastructure for heavy-duty trucks.
Using models developed at Argonne, the team found that installing one charging site, which could supply 100 e-trucks at a time, would involve a major infrastructure investment that could run costs higher than $21 million.
“Making this transition to electrification is going to be expensive, and we wanted to estimate those costs so we can start thinking about who pays for it,” said Rosner, who is the founding co-director of UChicago’s Energy Policy Institute.
Determining the actual cost of a charging station
At issue is the power needed to charge heavy-duty e-trucks. Such trucks require a 1-megawatt-hour battery, which would take 10 hours to charge on an average electric car charger. Current ultrafast chargers could potentially reduce that time to 5 hours.
It’s not realistic to expect truckers to recharge mid-day, but because truckers generally are limited to how many hours they can drive in a day (they may, for example, drive a maximum of 11 hours after 10 consecutive hours off duty), they must take long breaks – an ideal time to recharge their trucks.
When the team set out to study this issue, they focused on one of the most heavily trafficked trucking routes in the United States: the portion of Interstate I-80 that runs east-west throughout Illinois.
Because trucks would charge while the drivers rest, the team identified 20 potential e-truck charging locations along this 163-mile stretch, at both truck stops and rest stops.
But to build a charging station at an existing rest stop would require major infrastructure investment.
“This wouldn’t be like the charging stations you see around now for cars,” Rosner said. “It would require much more power.” The researchers found that, given the magnitude of power that e-trucks would need, such charging stations would likely require an on-site substation, since existing grid connections would not be able to handle the load.
Any potential charging station must also have a power unit to condition the voltage from AC to DC. Add to that the installation of Level 3 DC fast chargers for 100 truck slots, and the cost rises to $21.2 million.
Ultimately, the 20-year cost for one charging site would be more than $100 million.
The team also examined other “green” alternatives to a substation. The initial cost for a solar-powered charging site would be between $82 million and $139 million, they estimated. A nuclear reactor station would initially cost $141 million. A wind power station would initially cost up to $75 million. Each alternative also comes with its own issues. Power from wind turbines and solar panels fluctuates over time, for example, so they would require additional power storage systems.
“We hope that these numbers help start the conversation,” Rosner said. “Transportation officials and the utility companies need to start thinking about how they are going to do this, and who is going to pay for it. It’s going to be a major issue.”
Other researchers on the team include UChicago master’s student Sabrina Fields, recent UChicago master’s graduate Rashmi Muraleedhar, Argonne principal mechanical engineer Derek Kultgen, Argonne principal energy systems engineer Audun Botterud, former Argonne strategy development director Michael Ford, and Argonne senior nuclear engineer Richard Vilim.
This research was supported by the UChicago Joint Task Force Initiative, which helps Argonne and Fermilab achieve mission success by opening channels of frequent communication and collaboration across institutions.
Originally published by the UChicago Office of Science, Innovation, National Laboratories and Global Initiatives.