Speed Advice: dynamic speed advice near intersections

Context of Transport Climate Action

Stop and go traffic near intersections and on congested motorways has a large contribution to emissions. In-car dynamic speed advice helps to reduce stop and go traffic on motorways and near intersections. On motorways speed advice can reduce shockwave traffic jams. This is quite important since shockwaves are responsible for about 20% of the total delays on the Dutch motorway network (on some motorway up to 40%). Near intersections speed advice can also reduce the number of stops and therewith emissions especially in combination with optimization of traffic signal settings. TNO develops a demonstration App which gives speed advice on the entire route. This App builds upon a demonstration of shockwave reduction on the A270 and A58 motorways in the Netherlands. Speed advice on the entire route will be demonstrated for two motorways and a signalized intersection in the area Rotterdam-Delft-The Hague in the Netherlands.


The App gives speed advice on motorways and near intersections. For each vehicle that approaches a signalized intersection a speed advice is given based on the time to green, time to red and queue lengths. The advice is given in such a way that the throughput at the intersection is optimized and that the emissions are minimized. The speed advice on the motorway is based on data from loop detectors and/or floating device data (both can be used stand alone or in combination). Speed advice is given in such a way that the traffic flows smoother (= less unexpected braking and accelerating) and driving is more fuel-efficient. By consequence there are less emissions.



Speed advice on the entire route has been developed and funded by TNO, a dutch research institute. Communication with a traffic signal is arranged in cooperation with the Province South Holland (a Dutch regional government body) and Vialis, a consultancy.


  • A demonstration on the A270 showed that speed advice (in that case with adaptive cruise control) can improve the throughput with 10% – 25%.
  • By driving at a more constant speed, start and stop movements are avoided, which will reduce emissions, since the engine can operate at a constant power.

Potential for scaling up

Implementation is possible for all countries where there is floating car data (for instance from smartphones) or loop detector data (from the road) available. The expected impact depends on the data quality and density, the type of signal controls and the extent to which communication with the signal controls and between vehicles is possible. Key challenge is moving towards a fully cooperative and collaborative system.

For large scale implementation cooperation with a service provider is required. Furthermore, cooperation with local, regional and national governments is required to allow communication with traffic signals and to enable communication between vehicles.

Selected references




Netherlands, A58, A13, A4 – Kruithuisweg.






Europe, the Netherlands, Passenger Transport, Car, Technology, Mitigation




Maaike Snelder: maaike.snelder@tno.nl

In relation to A58 project:
Minister Schultz van Haegen: “Intelligent vehicles that communicate with each other are no longer science fiction. The technique is available and more and more drivers in the Netherlands can experience it. We will test which techniques are most promising to reduce shock waves. Successful techniques can be deployed on a national scale”