Why Developed Countries Apply Solar Road Stud

Why are solar road stud suggested to be installed on high-speed roads? Why do many developed countries in the world have installed large-scale solar road stud?
Solar road stud is a safe and green transportation solar energy product. During the day, solar panels absorb sunshine, transform solar power into electrical energy and store solar power in energy storage devices (batteries or capacitors). At night, the electric energy in the energy storage device is automatically converted into light (controlled by light control switch) and emits light in the dark condition.

solar road studs
In the dark, rainy, foggy days and other bad environment with short driving sight, if the vehicle deviates from the lane and presses the solar road stud, the driver can also timely detect the sound and bumpy feeling, causing alarm. In the case of insufficient light at night, the solar road studs will automatically flash and emit light. 
Usually, the solar road stud has active light and passive light. Even if the reflector of solar road stud is broken, it can remind the driver to drive safely, sketch out the road outline and guide the road.

solar road studs improve road safety
In the current national highway safety and security projects, more scientific and technological traffic safety facilities have been widely used, solar road studs are one of them, they play a due role in improving road traffic safety and reducing the occurrence of traffic accidents.
The practice has proved that the solar road stud plays an important role in drawing the road outline, guiding the driver's sight and eliminating the hidden danger in the rain and fog weather and in the curve. One belt and one road initiative, the peak of international cooperation, I believe that solar road stud will become the most shining star in the world security.