Summary
Honda, Taisei and Taisei Rotec have developed underlying technology for roads that wirelessly transfer power to EVs while they are moving. The companies plan further durability and power-transfer tests, with public-road demonstrations scheduled from Japan’s FY2027 onward.
Honda R&D, Taisei Corporation and Taisei Rotec Corporation have developed underlying technology for a road system that wirelessly transfers power to electric vehicles while they are moving. The companies say tests on a dedicated roadway in Saitama Prefecture helped verify technologies for the power-transfer system, road structures and construction methods. They plan further testing from late 2026 and public-road demonstrations from Japan’s 2027 fiscal year, which begins on April 1, 2027.
The system is being developed with large commercial vehicles in mind as well as passenger EVs. It uses magnetic coupling: power-transmitting equipment embedded in the road transfers energy to a receiver fitted to the vehicle. Honda calls the approach dynamic wireless power transfer, or DWPT.
How the road-based charging system works
The system has three main parts: a ground-based direct-current (DC) power supply, transmitter assemblies embedded in the road, and a vehicle-mounted receiver. Honda is developing the road assembly and vehicle system; Taisei is developing the DC power supply; and Taisei Rotec is working on road construction methods. All three companies are working on pavement structures, durability testing, upgrades and tests of power distribution and transfer.
The road assembly connects multiple power-transmitter units through DC distribution. Each unit combines an inverter and a coil, according to Honda. The company says this arrangement, paired with the ground supply, is designed to provide responsive and stable high-power transfer. Embedding the equipment in milled pavement is intended to make installation practical in existing roads and during later pavement renewal; the DC layout also reduces wiring and installation work, Honda says.
Testing for heavy traffic and higher power
A central engineering challenge is making the embedded equipment and surrounding pavement withstand heavy vehicles. Honda says the design was optimized for strength and durability, with testing aimed at road traffic that includes vehicles with a gross vehicle weight of about 20 tonnes.
The companies plan to build another test roadway at Taisei Group’s T-FIELD/TAMRA site starting in late 2026. Planned work includes a long-term loading test equivalent to 1 million wheel loads, using a load of 49 kN per wheel, as well as power-transfer tests and tests of measures to address electromagnetic-field leakage.
Further development is intended to verify performance at power outputs of up to 150 kW for potential use with large commercial vehicles, and to assess reliable transfer to vehicles travelling at high speeds. These are future test targets, rather than results reported for the system so far. The companies also plan to take part in a DWPT demonstration project on the Tateyama Expressway in Chiba, Japan, from FY2027 onward.
Honda expects in-motion power transfer could reduce how often EVs need to stop for charging. It says it will initially focus on potential applications in logistics and transportation, where vehicles may follow regular routes. Whether the road infrastructure can deliver the planned power and durability in real-world operation is the subject of the upcoming tests.