At the heart of the American Midwest, Indiana, known as the “Crossroads of America,” is becoming a hotbed for electric vehicle (EV) innovation. Purdue University engineers and the Indiana Department of Transportation (INDOT), under a pioneering “Cars Program Indot” initiative, are collaborating to make wireless charging for electric vehicles a highway reality. This ambitious project aims to enable everything from heavy-duty tractor-trailers to everyday passenger cars to charge wirelessly while driving, potentially transforming the future of transportation.
Construction is currently underway on a groundbreaking quarter-mile test track on U.S. Highway 231/U.S. Highway 52 in West Lafayette. This dedicated testbed will be used to rigorously evaluate a patent-pending system developed by Purdue’s brightest minds. The goal? To prove that this innovative technology can effectively deliver power to a massive electric truck speeding down the highway.
Indiana Governor Eric Holcomb proudly highlighted this initiative at COP27, a major United Nations environmental conference in 2022, stating, “Thanks once again to some engineers and pioneers from Purdue, we’re developing the world’s first highway test bed for wireless charging. Yes, we will be testing whether concrete can charge passing trucks — and don’t bet against a Purdue Boilermaker.” This bold statement underscores the state’s commitment to embracing cutting-edge technology and its confidence in Purdue’s engineering prowess.
Image: Highway construction underway for wireless EV charging testbed in Indiana, showcasing the “cars program INDOT” initiative in action.
The construction of this revolutionary test bed, which commenced on April 1st and is projected to continue throughout the fall, marks a significant step forward. A fully electric truck, provided by Indiana-based industry leader Cummins Inc., will be the star of the pilot program scheduled to launch next year. This real-world testing is crucial to validating the technology and paving the way for the ultimate vision: electrifying a section of Indiana interstate within the next four to five years.
The Unique Challenges and Advantages of Highway Wireless EV Charging
While other regions globally are exploring wireless EV charging roads, Indiana’s project tackles a particularly complex challenge: highways and heavy-duty vehicles. The speed at which vehicles travel on highways, compared to slower city streets, necessitates significantly higher power levels for effective wireless charging.
The Purdue-designed system is engineered to operate at power levels far exceeding current US demonstrations. This high-power capability is not just crucial for energy-hungry heavy-duty trucks but also inherently supports the lower power demands of lighter vehicle classes, making it a versatile solution for a broad spectrum of EVs.
Why Prioritize Trucks for Electrified Highways?
Indiana’s strategic geographical location positions it as a critical artery for national freight movement. Remarkably, 80% of the continental U.S. is within a single day’s drive from Indiana’s extensive highway network. Electrifying Indiana’s highways, especially with a focus on heavy-duty trucks, offers the most impactful approach to reducing greenhouse gas emissions in the transportation sector and maximizing the economic viability of EV infrastructure development.
Heavy-duty trucks are major contributors to greenhouse gas emissions within the U.S. transportation landscape due to their sheer volume in interstate traffic and substantial fuel consumption. They are the workhorses of our economy, constantly transporting goods across vast distances.
Nadia Gkritza, a distinguished Purdue Professor of Civil Engineering and Agricultural and Biological Engineering, explains, “The so-called ‘middle mile’ of the supply chain, which refers to all the travel heavy-duty trucks have to do to carry goods from one major location to another, is the most challenging part of the transportation sector to decarbonize.”
Image: Cummins electric truck designated for testing the Purdue wireless charging system as part of the “cars program INDOT” initiative.
However, wireless highway charging for electric heavy-duty trucks presents a game-changing opportunity. By enabling trucks to charge or maintain their battery charge while in motion, battery sizes can be significantly reduced. This translates to increased cargo capacity and dramatically lower operating costs for EV freight transportation. Considering that trucking is the largest contributor to the U.S. GDP among freight transportation modes, reducing costs for electric heavy-duty trucks can stimulate substantial investment in nationwide electrified highways, benefiting all classes of electric vehicles.
John Haddock, a Professor in Purdue’s Lyles School of Civil Engineering, emphasizes the system’s capabilities, stating, “We’re developing a system that has the power to charge semitractor-trailers as they move 65 miles per hour down the road.”
Electrified Highways: Charging EVs Like Smartphones
The wireless charging technology being pioneered at Purdue mirrors the convenience of wireless smartphone charging. Imagine highway pavement capable of transferring power to EVs through magnetic fields, similar to placing your phone on a charging pad.
Steve Pekarek, Purdue’s Edmund O. Schweitzer, III Professor of Electrical and Computer Engineering, clarifies the concept: “If you have a cellphone and you place it on a charger, there is what’s called magnetic fields that are coming up from the charger into that phone. We’re doing something similar. The only thing that’s different is the power levels are higher and you’re going out across a large distance from the roadway to the vehicle.” He further simplifies the innovation, “This is a simple solution. There are complicated parts of it, and that we leave to the vehicle manufacturers.”
The Purdue wireless charging system design incorporates transmitter coils embedded within dedicated highway lanes, beneath standard concrete pavement. These coils will transmit power to receiver coils installed on the underside of electric vehicles.
While other wireless EV charging projects utilize similar transmitter and receiver coil technology, the Purdue system stands apart by being specifically designed for the high-power demands of heavy-duty trucks. The innovative coil design accommodates a broader power range, eliminating the need for complex multi-coil receiver setups on trailers, thus simplifying the overall system and enhancing practicality.
Furthermore, Purdue’s transmitter coils are uniquely engineered for integration within concrete pavement, which constitutes a significant 20% of the U.S. interstate system. Many existing coil designs are limited to asphalt pavement, making Purdue’s concrete compatibility a crucial advantage for widespread highway deployment.
Aaron Brovont, a Research Assistant Professor in Purdue’s Elmore Family School of Electrical and Computer Engineering, succinctly captures the user benefit: “The whole idea is if you can charge your car on the road while in motion, then you’re basically riding for free.”
Image: Purdue professors inspecting concrete pavement embedded with wireless power transfer technology, central to the “cars program INDOT” project.
Extensive testing has been conducted on 20-foot sections of both concrete and asphalt embedded with transmitter coils to evaluate their structural integrity under heavy truck loads. Machines simulating heavy semi-truck axle loads have been used to repeatedly stress-test the pavements. Complementary lab tests have validated the electromagnetic performance of both the transmitter and receiver coils.
Building the Foundation for Nationwide Electrified Highways
This groundbreaking research has garnered attention from major news outlets including The New York Times, CNBC, and Popular Mechanics, highlighting its potential to reshape the future of EV charging infrastructure.
Purdue’s partnerships extend beyond Indiana, reaching across the nation. The project is supported by INDOT through the Joint Transportation Research Program at Purdue and is also affiliated with ASPIRE (Advancing Sustainability through Powered Infrastructure for Roadway Electrification), a fourth-generation National Science Foundation Engineering Research Center. ASPIRE is dedicated to accelerating the advancement of electrified transportation in all its forms.
Purdue is a founding member of ASPIRE, with Professor Gkritza serving as the campus director for ASPIRE’s Purdue operations. Headquartered at Utah State University, ASPIRE unites academia, research, and real-world testing with over 400 members from ten partner universities and more than 60 industry, government, and non-profit partners.
ASPIRE members at Purdue and Cummins are also collaborating on a U.S. Department of Energy-funded project to develop a comprehensive EV charging and hydrogen fueling plan for medium and heavy-duty trucks along the critical Interstate 80 corridor in the Midwest, spanning Indiana, Illinois, and Ohio. This plan will specifically evaluate the integration of the wireless power transfer technology being tested in West Lafayette.
Professor Gkritza envisions a strategic deployment of this technology, noting, “We don’t envision 100% of the roads being electrified. But we see the potential for dynamic wireless power pavement technology as complementary to an expanding network of EV charging stations that we will see very soon here in the U.S. We feel it would be useful in areas where charging stations are scarce in underserved communities, even supporting transit routes where initial charging at the depots and terminal stations might not be enough and there might need to be some charging in between the routes.”
Researchers anticipate that achieving full power wireless charging for EVs at highway speeds may take 20 to 30 years. Ultimately, the adoption of receiver coils in EVs will depend on vehicle manufacturers.
Dionysios Aliprantis, a Purdue Electrical and Computer Engineering Professor, remains optimistic, stating, “The technical obstacles that we need to overcome are not insurmountable. Those can be overcome with proper design.”
The Purdue team is confident that their research will demonstrate the viability of electrified highways and encourage industry adoption. As Professor Haddock aptly concludes, “We are Purdue University, where the difficult is done today and the impossible takes a bit longer.”
Image: Purdue researchers measuring electromagnetic performance of coils for wireless EV charging, crucial for the “cars program INDOT” initiative.
ASPIRE’s Purdue location is integrated within LEAPS (Leading Energy-Transition Advances and Pathways to Sustainability), a new Purdue Engineering Initiative. LEAPS aims to drive energy transition innovations, transform energy-focused education, and accelerate technology translation through academic-industry partnerships.
Purdue Innovates Office of Technology Commercialization has filed patent applications for the team’s innovations. Industry partners interested in exploring development or commercialization opportunities are encouraged to contact Matt Halladay at Purdue Innovates.
About Purdue University
Purdue University is a top-tier public research institution renowned for its excellence and scale. Consistently ranked among the top 10 public universities in the U.S., Purdue is committed to delivering high-quality education and groundbreaking research. With over 105,000 students across various modalities and locations, including nearly 50,000 at its West Lafayette campus, Purdue remains dedicated to affordability and accessibility, having frozen tuition for 13 consecutive years. Purdue continues to pursue the “next giant leap” through strategic initiatives, including its new urban campus in Indianapolis, the Mitchell E. Daniels, Jr. School of Business, and Purdue Computes.
