What you'll learn:
- What is dynamic wireless charging?
- Electreon's effort to build wireless roads abroad.
- Wireless road projects in the U.S.
Researchers have long theorized about devices installed in highway pavements that would deliver electrical energy to battery electric vehicles (BEVs) on the road using a magnetic field. Yet even with much progress being made in BEV technology, in terms of hardware and infrastructure, EV systems still depend on stationary recharging, which takes significantly more time than refueling an ICE- or hydrogen-powered vehicle.
However, there are signs that this may soon be changing. Dynamic wireless charging could revolutionize transportation and accelerate the switch to electric mobility by using copper coils fitted under the asphalt, enabling EVs to charge their batteries while on the move.
To transmit electricity wirelessly, inductive charging uses coils mounted in a transmitter and connected to a source of electricity as well as a receiver mounted on the vehicle. It requires the receiver on the vehicle to be aligned with the line of coils in the road surface.
In a 2021 study on the most efficient and sustainable large-scale technologies and strategies to achieve net-zero transport emission, France’s Transportation Ministry concluded that if deployed at large scales, a wireless electric road system could reduce CO2 emissions from road freight transport by 86% compared to diesel fuel. In France, the transportation sector represents one-third of the country’s greenhouse gas emissions, and 95% of these emissions come from road transport. Without the electric road system, electric heavy-duty trucks would have to be equipped with extremely large batteries and stop to charge at high-power charging stations.
The French study also proposed a plan to deploy electric road systems over nearly 5,000 km by 2030, and nearly 9,000 km by 2035, highlighting the critical importance of the technology as a significant piece of the puzzle to achieve net-zero emissions.
Electreon’s Global Wireless-Road Projects
Multiple efforts are underway to develop wireless-charging road systems. The Israeli firm Electreon has won tenders in France and Norway to install small sections of its wireless “Electric Roads System” aimed at fleet operators. Electreon places copper coils just below the surface of the road—along highways, at bus stations, in parking lots, and at logistics centers.
Deployment takes place at night to minimize disruption as a portion of the asphalt needs to be removed and replaced. The coils are then covered with asphalt and the Electric Road is ready to begin charging EVs.
Other than that, the system can connect to existing power grids without the need for additional infrastructure or transformation stations. It uses management units placed on the sides of the road to communicate with the receivers on the vehicles and transfer energy. The end-to-end solution includes underground infrastructure, vehicle technology, and charging management software.
In 2019, Electreon completed the deployment of its dynamic wireless-charging system on a 1.65-km (1.02-mile) public road in Gotland, Sweden. Since then, a fully electric, 40-ton truck and trailer have successfully conducted tests on a road between the airport and city center of Visby, reaching speeds of up to 80 km/h while receiving an average power of 70 kW from the electrified roadway.
Following on the heels of this effort, Bpifrance, the French public sector investment bank, has selected Electreon’s Electric Road System for a project on a 2-km section of the A10 highway, southwest of Paris. Bpifrance, together with the relevant French Ministries, chose Electreon and its consortium partners for the project as part of its strategy to promote decarbonized mobility. The consortium is led by VINCI Autoroutes with several additional partners to Electreon—VINCI Construction, Hutchinson, and Gustave Eiffel University. The initial phase of the project will focus on charging commercial e-fleets while they drive.
In this project, Electreon plans to unveil its next-generation product with significantly increased power-transfer capacity, additional software features such as real-time monitoring, and a more robust architecture. Specifically designed for dense traffic corridors on public highways, Electreon will deploy the Electric Road as both a two-kilometer dynamic wireless charging road and a stationary wireless-charging station. This charging infrastructure is said to support all vehicle types and classes.
On top of that, Electreon will provide a 40-ton truck as well as a bus, and will invite multiple leading automotive partners to benefit from the company’s new product capabilities. In addition, a kilometer-long strip in the German town of Balingen will, later this year, host a public trial of a wireless-charging road.
Michigan’s Department of Transportation is also testing the technology this year. MDOT and Electreon have signed a five-year agreement for a pilot program. The total estimated cost is $1.9 million.
Also in the U.S.
In a patent application, titled “Roadway Charging Coil Alignment and Monitoring,” published on July 20, 2023, and originally filed on January 20, 2022, Ford discusses embedding inductive-charging coils in the road and using them to charge moving vehicles. The patent aims to apply wireless inductive charging to vehicles in motion.
As Ford points out, to ensure efficient charging, the receiver on the vehicle needs to be aligned with a line of coils in the road surface. The company further notes that drivers could maintain alignment by following lane markings or be guided by a camera or other sensors designed to read lane markings.
Specifically, though, Ford proposes equipping vehicles with ground-penetrating radar. The radar would help the vehicle locate the charging coils, and the data could be used to automatically adjust the steering for optimal charging.
The Indiana Department of Transportation and Purdue University are working on developing what’s said to be the world's first contactless wireless-charging concrete pavement highway segment for electric cars. They’re working with German startup Magment GmbH. How does it work? A magnetizable concrete would be used on highways in Indiana that would charge the cars as they drove along.
Magnetizable asphalt will enable high-efficiency and cost-effective construction of electrified roads that will supply energy to vehicles of the future. Current available technologies use copper coils with or without magnetic ground pads, such as Magment’s patented magnetizable road construction materials. An antenna mounted to the vehicle bottom passes through the magnetic field, generating an electrical current that charges the batteries.
The project is part of the Advancing Sustainability through Power Infrastructure for Road Electrification (ASPIRE) Initiative, an Engineering Research Center funded by the National Science Foundation.
The testing phase of the project is complete. Teams are working on the design for the testbed strip, which will be located on US 231 and US 52 in West Lafayette, Ind.
Still, hurdles remain that must be overcome. All of the electric charging road concepts have to be interoperable, enabling rival vehicle models to charge on the same system to avoid duplicating the technology. What’s more, installing underfloor charging pads can be prohibitively expensive. Such a system would require a large infrastructure investment, and the roads would need to be chosen wisely for greatest impact.