For the first time in the U.S., a roadway has wirelessly charged an electric heavy-duty truck driving at highway speeds, demonstrating key technology that could help lower the costs of building electrified highways for all electric vehicles to use.
Pictured above is an electric Cummins heavy-duty truck charging as it drives along a test segment on U.S. Highway 52/U.S. Highway 231 in West Lafayette, Indiana. Purdue University photo by Kelsey Lefever.
This experimental highway segment tests a patent-pending system designed by Purdue University engineers. The quarter-mile segment was built by the Indiana Department of Transportation (INDOT). “INDOT is proud to partner with Purdue on this project,” said INDOT Commissioner Lyndsay Quist. “While there is still more to explore, we are seeing what the future could hold for heavy-duty EV charging and transportation.”
INDOT embedded these Purdue-designed coils before covering them with concrete pavement. The coils transmit power to receiver coils attached to the underside of an electric heavy-duty truck. Purdue University photo by Kelsey Lefever.
The team installed transmitter coils in specially dedicated lanes within the concrete pavement. The coils send power to receiver coils attached to the truck’s underside. “Transferring power through a magnetic field at these relatively large distances is challenging. And what makes it more challenging is doing it for a heavy-duty vehicle moving at power levels thousands of times higher than what smartphones receive,” said Dionysios Aliprantis, a Purdue professor of electrical and computer engineering.
Why design electrified highways for trucks first?
Since trucking contributes the most to U.S. gross domestic product compared to other modes of freight transportation, lowering costs for heavy-duty electric trucks could help attract more investment into electrifying highways that all vehicle classes would share.
If electric heavy-duty trucks could charge or stay charged using highways, their batteries could be smaller in size and they could carry more cargo, significantly reducing the costs of using EVs for freight transportation. Electrified highways could also allow the batteries of passenger cars to be smaller, reducing the cost of EVs along with the vehicle weight, delivering greater travel efficiency.
Pictured is the Purdue University team of professors instrumental in the development of the charging concrete highway. From the left: Dionysios Aliprantis, Aaron Brovont, Nadia Gkritza, Steve Pekarek and John Haddock. Purdue University photo by Kelsey Lefever.
The Purdue system demonstrates “dynamic wireless power transfer,” with “dynamic” referring to vehicles in motion. A few other states and countries have also begun testing roads designed to enable dynamic wireless power transfer. But making this possible for highways — and particularly for semis and other heavy-duty vehicles — is a unique challenge. Because vehicles travel so much faster on highways than city roads, they need to be charged at higher power levels.
The Purdue-designed wireless charging system works at power levels much higher than what has been demonstrated in the U.S. so far. Using the test segment in West Lafayette, this system delivered 190 kilowatts to a truck traveling at 65 miles per hour.
“To put that in perspective, 200 kilowatts are on the scale of about a hundred homes,” said Steve Pekarek, Purdue’s Edmund O. Schweitzer, III Professor of Electrical and Computer Engineering.
Purdue University photo by Kelsey Lefever.
The researchers have disclosed their innovation to the Purdue Innovates Office of Technology Commercialization, which has applied for a patent on the intellectual property. Industry partners interested in developing or commercializing the work should contact Matt Halladay, Senior Business Development and Licensing Manager, at mrhalladay@prf.org about track codes 2022-ALIP-69682, 2024-PEKA-70401 and 2024-PEKA-70402.
Big thanks a tip of the hard hat to Kayla Albert for all of the information in this story.