Earlier this month, Volkswagen and Siemens tested a smart light system in Wolfsburg, installing traffic signal systems that broadcast what color their lights were about to flash. Cars driving on that section of the road could receive the information and then regulate their speed so as to minimize stopping or slowing time and be able to drive straight through when the light flashed green. The system worked through a set of sensors transmitting via WiFi. At two of the crossroads on that smart-light-equipped stretch of road, Volkswagen and Siemens also trialled a system of sensors designed to detect pedestrians and cyclists and transmit that information to the cars on the road.

BMW have experimented with a 5-to-1 system that counts down to green. Mercedes insists that its cars, if driven at a speed within a certain range, will encounter green lights almost exclusively.

Ford and Honda are also in the mix, with goals of cutting wait times and, more importantly, emissions. Honda has already trialled the "smart intersection" concept in the U.S., implementing a camera on each corner of an intersection to create a 360-degree view and sending that information to specially equipped cars. Ford has taken the wraps off technology that allows cars to "talk" to each other.