In recent years, the spread of electric vehicles has been steadily increasing, leading to a growing demand for related infrastructure development. While there have been criticisms about the long charging time, innovative technologies for "charging while driving" have recently been developed and are attracting attention.

NEXCO East Japan, a Japanese expressway operator, is already planning to start a new experiment for electric vehicle charging in 2025. They have decided to participate in a project to install electric coils under roads in the Osaka area to create a system for wirelessly transmitting electricity to electric route buses. This will enable buses to charge their batteries non-contact while stopped.

In 2029, they plan to conduct a charging while driving experiment on the expressway mainline. The system will automatically charge electric vehicles when they drive in designated "power supply lanes." They are accelerating the development of related technologies and improving the road surface materials to make this possible.

The "charging while driving" technology currently under development is broadly divided into electric field coupling and magnetic field coupling methods. The electric field coupling method uses electrodes to create an electric field, while the magnetic field coupling method uses electromagnetic coils to generate a magnetic field to transmit power.

Ceramic aggregates used in the electric field coupling method are known to have low water absorption, resulting in high transmission efficiency. Using these aggregates for road paving is expected to achieve a high transmission efficiency of about 70%. This is because ceramic aggregates have a low moisture content, minimizing electrical losses.

The ability to charge while driving is expected to significantly increase the utility of electric vehicles. Currently, the driving distance possible on a single charge is limited, making long-distance driving difficult. However, the ability to charge while driving will greatly alleviate this restriction.

As charging while driving technology advances, it is expected that simple charging will become possible in a time similar to visiting a gasoline station. This will contribute to the widespread adoption of electric vehicles. The Japanese government has set a goal of 100% electric vehicle share in new car sales by 2035, and infrastructure development is essential to achieve this target.

Furthermore, with the commercialization of charging while driving, electric vehicle battery capacities may be reduced compared to current levels. Since charging will be more convenient, there will be no need to install batteries with excessive capacities for long-distance driving. This is expected to lead to lighter vehicles and lower prices.

Meanwhile, electric vehicle running costs are also expected to be significantly reduced. According to government agency surveys, the current electricity cost for driving 100 km in a typical household is about 310 yen, while for a gasoline car, it is about 690 yen. This means that fuel costs per kilometer are reduced to less than half. This cost-saving effect is expected to be even greater as charging becomes possible in regular households.

With the government and private sector joining forces to accelerate the development of electric vehicle-related infrastructure, the electric vehicle era is expected to accelerate in the future. Electric vehicle adoption is already increasing globally. The realization of charging while driving will dramatically enhance the utility of electric vehicles, providing advantages in fuel efficiency and driving range. To accelerate the transition to a zero-emission vehicle era, continuous technological investment and efforts from the government and industry are likely to be necessary.