England has begun installing SolarLite Smart Studs on some of their darker stretches of road. The solar studs have a little solar panel in them, along with an LED light and traditional reflecting surface.
Drivers on the retrofitted roads enjoy 10 times more visibility (90 meters to 900 meters) with the new in-road lights.
As a result, drivers have 10 times more notice to adjust to changes in road direction. In some scenarios, the lights replace overhead street lamps, completely eliminating the need for the roads to be on the electric grid.