Wireless EV Charging: The Detroit Road Test

The concept of charging an electric vehicle while driving down the highway has moved from science fiction to reality in the Motor City. Michigan has officially launched the first public roadway in the United States capable of wirelessly charging electric vehicles as they move. This pilot program on 14th Street in Detroit marks a significant shift in how infrastructure planners and automotive engineers approach the challenge of EV range and battery capacity.

The Technology Under the Asphalt

The technology powering this stretch of road comes from Electreon, an Israel-based developer of wireless charging solutions. The system works through magnetic resonance induction, which is similar in principle to how you might charge a modern smartphone or electric toothbrush, but on a much larger and more durable scale.

Construction crews installed copper coils roughly two to three inches beneath the surface of the pavement. These coils are connected to the power grid via management units located on the side of the road. When a vehicle equipped with a specific receiver passes over the coils, the system detects it and transfers energy wirelessly through the air gap between the road and the vehicle’s undercarriage.

This process is known as dynamic wireless power transfer. The pilot in Detroit also tests static charging, which allows vehicles to charge wirelessly while they are parked or stopped at a red light or bus stop.

Key Technical Specs

• Provider: Electreon
• Mechanism: Inductive charging via buried copper coils
• Activation: The coils only activate when a vehicle with a verified receiver passes over them.
• Safety: The system is safe for pedestrians, drivers, and animals to walk over, as the energy transfer is localized and specific to the receiver.

Location and Partnership Details

The quarter-mile test segment is located on 14th Street, right next to the iconic Michigan Central Station. This area has been redeveloped by Ford Motor Company as an innovation district dedicated to the future of mobility.

This project is not a solo effort. It is the result of a five-year agreement involving several major stakeholders:

• Michigan Department of Transportation (MDOT): Overseeing the integration into public infrastructure.
• City of Detroit: Managing local logistics and roadways.
• Electreon: Providing the hardware and software technology.
• Ford Motor Company: Providing the test vehicle.
• DTE Energy: Handling the grid connection and power supply.

For the initial demonstration, a Ford E-Transit commercial van was retrofitted with Electreon’s rubber-encased receiver. During the live test, the van was able to charge at a rate of up to 19 kilowatts while moving. While this is slower than a DC fast charger, the goal of dynamic charging is not necessarily to fill a battery from empty to full in minutes. Instead, the goal is to maintain the battery level or slow the rate of discharge while the vehicle operates.

Solving the "Range Anxiety" Problem

The primary argument for electrified roads is the potential reduction in battery size. Currently, automakers pack massive, heavy, and expensive lithium-ion batteries into vehicles to ensure they can travel 300 or 400 miles on a single charge.

If roads could charge vehicles as they drive, cars would not need such large energy reserves. A smaller battery makes a vehicle lighter, more efficient, and significantly cheaper to produce. This is particularly relevant for commercial fleets.

The Use Case for Fleets

The Detroit pilot focuses heavily on the commercial application. Delivery vans and public transit buses follow fixed routes. If key sections of these routes (or the bus stops themselves) were electrified, these heavy-duty vehicles could run all day without stopping to plug in. This eliminates downtime and reduces the strain on the electrical grid that occurs when hundreds of buses plug in simultaneously at a depot overnight.

Weather and Durability Concerns

A common question regarding Michigan infrastructure involves winter weather. The state is notorious for freeze-thaw cycles that create potholes, as well as heavy snowfall.

Electreon and MDOT have stated that the coils are protected by the asphalt and are designed to withstand the harsh environment. The magnetic field is unaffected by snow, ice, or rain. In fact, the heat generated during the energy transfer might even help melt small amounts of snow directly above the coils, though it is not a replacement for snowplows.

The coils are modular. If a section of the road is damaged or a coil fails, road crews can strip a small section of pavement to repair that specific unit without tearing up the entire street.

What This Means for Consumer Drivers

It is important to clarify that this road will not charge your personal Tesla or Chevy Bolt today. Current consumer EVs do not have the necessary receiver hardware installed on their underbelly to communicate with the Electreon coils.

However, the automotive industry is watching this pilot closely. If the infrastructure proves reliable and cost-effective, automakers may begin offering wireless charging receivers as a factory option or standard feature in future models. The Society of Automotive Engineers (SAE) has already established standards for wireless power transfer to ensure different car brands can use the same charging pads and roads.

Future Expansion and Costs

This project in Detroit is just the beginning. MDOT contributed $1.9 million toward the project, with Electreon covering the remaining costs. While the per-mile cost is currently high due to the experimental nature of the technology, proponents argue that costs will drop as production scales up.

Other states are following suit. The Indiana Department of Transportation is working with Purdue University on a similar project using a different type of concrete designed to magnetize efficiently. As these pilots conclude, the data gathered regarding efficiency, road durability, and maintenance costs will determine if wireless charging lanes become a common sight on American interstates.

Frequently Asked Questions

Does the road shock you if you walk on it? No. The system is designed to only activate when it communicates digitally with a compatible receiver on a vehicle. If you walk across the road, or if a squirrel runs across it, the coils remain inactive and emit no power.

How much does it cost to use the road? For the pilot program, the focus is on testing technology rather than billing. In a future commercial deployment, the system would identify the vehicle via its receiver and bill the driver automatically, similar to how an E-ZPass or toll transponder works today.

Will this work if the road is covered in snow? Yes. Magnetic resonance induction works effectively through air, asphalt, ice, and snow. The physical barrier of winter precipitation does not block the magnetic field required to transfer energy.

Can any electric car use this road? Not currently. The vehicle must be equipped with a specific receiver pad on the bottom of the chassis. Currently, this requires a retrofit, but manufacturers may build this technology into future vehicles if the infrastructure expands.