Reducing Traffic Congestion by informing approaching vehicles of the best average speed to pass through on green. GLOSA was a feasibility trial.
Traffic congestion is a significant source of frustration and increased emissions in urban areas. It is well established that driving at a steady pace uses significantly less fuel. Smart motorways have also proven that moving heavy traffic speed without stop/start increases the overall flow of traffic through a road system.

In urban environments junctions are frequently controlled by traffic lights to manage flows from multiple directions efficiently. The down side of this is that traffic delayed at traffic lights uses more fuel and slow responses can cause unnecessary delays.

The GLOSA project tested the theory that giving drivers warning of time to traffic light changes would allow for a more planned approach to lights, smoothing traffic flows and improving both fuel consumption and journey times.
A 6km stretch of the A45 Coventry road in Birmingham was used for the trial,. This road is one of the major traffic corridors into the city and carries very heavy flows at peak times.
The technology was fitted to 10 sets of lights and sent details to smartphones in vehicles using the road system. The system also gave drivers the optimal speed with which to approach the junctions.
It reduced journey times through the test stretch of road by 7%.

Resources needed

The project was financed with £300,000 from the UK Department of Transport. The project was managed by 1 staff member form Birmingham City Council with partnership from Amey (Infrastructure and servers) Eastpoint (Coding SME) and SGTI (Traffic flow consultants)

Evidence of success

GLOSA demonstrated that it is possible to improve journey times through this approach. It was successful in doing that and proved that that the principle innovation required is in programming rather than hardware.
Measured journey times through the light with commercial test drivers showed that it improves journey times by an average of 7%. Funding has been obtained to extend the trial and gain more objective data on improved journey times.

Difficulties encountered

Principle difficulties lay in establishing that the information was available and in creating the programming required to share the data.

Potential for learning or transfer

This good practice takes information available from old technology, and innovates by making it available to vehicle drivers.

Traffic light controlled traffic systems exist in practically every European city. This trial proves that the concept is both scale able and cost effective.

Development is required in terms of an app to work with either Mobile Phone systems or in vehicle computing to provide the data to drivers. The work done so far is open source and can be transferred and developed by others in cooperation.

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Main institution
Coventry University Enterprises Ltd
West Midlands, United Kingdom
Start Date
March 2017
End Date
March 2018


Tess Lukehurst Please login to contact the author.

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