One silver lining of the Covid-19 pandemic has been a major drop in air pollution thanks to the dramatic plunge in the number of cars on the roads. A new AI-powered smart technology system aims to help keep those pollution levels down. And all by using just traffic lights.

The system, has been developed by Surrey-based New Wireless, which already supplies 20 local UK authorities with pollution sensors and communication systems. It’s due to be tested on the Wolverhampton ring road later this year, with several other local councils keeping a close eye on the impact on air pollution in the area.

So how do simple traffic lights help cut air pollution? The AI algorithms are trained on historical data and constantly analyse current air pollution data and traffic levels. That allows the system to predict rises in air pollution levels up to an hour before they become a reality. When air pollution is forecast to increase beyond desired levels, the timing sequence on traffic lights is altered to delay the arrival of larger numbers of cars in risk areas.

The system can hold drivers headed in the direction of air pollution build up at traffic lights for up to 20 seconds longer than average, with others heading in directions where the air is cleaner benefitting.

Source: The Times

Wolverhampton traffic manager John Charles hopes the system trial will show the potential to keep the city’s air pollution level within legal nitrogen dioxide levels without the need to introduce daily entry fees for drivers. There city fears the need to introduce charges similar to London’s Congestion Charge would hurt businesses that rely on customers who arrive by car.

Mr Charles states:

“We need to explore alternatives to keep the city centre open. We are looking to see whether different biasing [of traffic light timings] can improve the traffic flow through at the expense of some of the other routes where air quality is not as bad. It’s about spreading the load to try to improve air quality.”

 The big improvement on other systems is that they rely on sensors measuring the current level of air pollution. This one works an hour in advance, preventing dangerous levels building up in the first place. It’s a delicate balancing act as holding traffic longer at lights can also lead to a rise in pollution at those spots but the system is able to carefully manage that risk and find the right ebb and flow of traffic to optimise emissions concentrations.

AA president Edmund King wasn’t quite as convinced, commenting:

“Whilst well intentioned this technology could easily backfire by holding up traffic, prolonging idling and moving the problem elsewhere. Rather than holding up traffic, we need to accelerate the move to cleaner, greener vehicles. Ironically the pandemic may bring air quality improvements in the longer term with 22 per cent of drivers saying they will drive less after lockdown and more people saying they will continue to work from home.”

Birmingham, Leeds and Bath had all planned the introduction of daily charges for vehicles with higher emissions levels but the step has now been pushed back to at least January next year. The Covid-19 pandemic means pollution levels have dropped anyway and resources also focused elsewhere. If the Wolverhampton trials of the New Wireless system prove effective, they may never need to be introduced at all.