With the intensification of environmental crises and increasing global commitments to reduce greenhouse gas emissions, electric vehicles (EVs) are rapidly expanding as clean and efficient alternatives to vehicles equipped with internal combustion engines. Despite significant advances in battery technology, power electronics, and charging infrastructure, today’s electric vehicles still face a set of technical, economic, and operational challenges that have prevented their widespread deployment worldwide. First, their heavy dependence on fixed charging stations requires careful planning for daily and intercity trips. The charging process, depending on the type of charger, can take from a few tens of minutes to several hours, effectively imposing unwanted downtime on the driver. In such a context, a bold and revolutionary idea has been proposed: the dynamic and wireless transfer of power from the road surface to moving vehicles. A concept that, if successfully implemented, could overcome the fundamental limitations of classic electric vehicles and take a big step towards clean, sustainable and smart transportation.
What are charging roads?
Charging roads, or so-called energy-generating roads, are smart and advanced infrastructures that, by using wireless power transfer technologies, enable the charging of electric vehicles on the move and without stopping. In these systems, the roadbed is not only the path of the vehicle, but also acts as an active and sustainable energy source.
Engineering methods for transferring energy from the roadbed
Inductive transfer
In this charging road technology, a set of primary coils are embedded in the underlying layers of the road. By passing alternating current (AC) through these coils, an oscillating magnetic field is produced. Secondary coils mounted on the underside of the vehicle receive this magnetic field and convert it into an electric current through the process of electromagnetic induction.
Conductive Transmission
In this method, metal rails or current-carrying channels are installed in the roadbed. Vehicles are equipped with a movable electrical pickup arm that makes physical or quasi-physical contact with these rails. Electrical current—usually low-voltage DC or precisely controlled AC—is transmitted from the roadbed to the vehicle’s power system.
Radial Transmission
This technology, which is still in the research and laboratory stage, works by directly transmitting energy in the form of targeted beams from sources such as infrared lasers, microwaves, or focused radio waves to receivers on the surface or roof of the vehicle. Antennas or receiver panels convert the received energy into usable electrical current.
Practical examples and global projects
In recent years, several leading countries in the field of transportation and energy engineering have implemented pilot and semi-industrial projects in the field of dynamic energy transfer from the roadbed to vehicles. The most important practical examples of this technology are introduced below.
Sweden: Near Arlanda Airport, a test section of charging roads with a length of approximately 2 km has been developed using conductive technology. On this route, metal charging rails have been installed in the center of the road, which are intelligently activated only when a vehicle is present. The system is equipped with an advanced safety mechanism that ensures complete power cut if the vehicle connection is not detected.
South Korea: South Korea’s KAIST University is one of the pioneers in the research and development of dynamic charging technology with the development of the Online Electric Vehicle (OLEV) system. In this system, coils are installed in the path of electric buses that, when activated momentarily, transfer electrical power to the vehicle through induction. In pilot projects implemented in the cities of Gomy and Seoul, the energy efficiency and magnetic interference of the system have been precisely measured and optimized.
