As part of a series of initiatives to improve air quality in the city, on 8 April 2019 Transport for London (TfL) is to enforce an Ultra-Low Emission Zone (ULEZ) in central London. From then, most vehicles, including cars and vans, will have to either meet new, tighter exhaust emission standards, or pay a daily charge to travel within the ULEZ area. From October 2021, this area will be expanded to include the whole of inner London, bounded by the city’s North and South circular roads.
At the heart of the ULEZ will be a software solution developed and installed by Siemens Mobility. The software will be integrated with existing roadside sensors and automatic number plate recognition (ANPR) cameras, which already form part of TfL’s congestion charging scheme.
Among the company’s portfolio of software solutions is Aimsun Next mobility modeling software, which includes a London Emissions Model (LEM). The LEM was developed by the Institute of Transport Studies, University of Leeds, for TfL and then integrated into Aimsun Next in order to enhance the accuracy of emissions predictions.
The emissions model can be used to inform the urban traffic control system, enabling environmental considerations to form a part of the overall traffic management strategy; for example, signal timings could be adjusted to strategically adjust the flow of traffic when pollution levels rise.