Traffic congestion schemes, of increasing significance in urban centers where there are concerns about pollution or the capacity of streets to accommodate a large number of vehicles during peak hours, seek to exclude classes of motor vehicles (for example cars owned by non-residents) or to allow entry of vehicles on a selective basis (e.g. at a particular time or subject to a financial penalty). In essence most schemes involve charging for use of public streets and have thus proved to be controversial, although sometimes supported by residents of the particular precinct.
ANPR Systems (Automatic Number Plate Recognition) has been used in such schemes to identify what vehicles are traversing a location, on the basis that the technology is less "invasive" than electronic tagging systems that require users to gain a RFID tag for the particular driver or vehicle. The registration database is typically linked to a billing system, with ANPR Systems (Automatic Number Plate Recognition) being used to identify 'authorized' vehicles (which have usually paid for the privilege of using the local road network) and non-authorized vehicles, which are automatically issued with a fine.
The UAE congestion pricing scheme (centered on a standard charge for private cars and commercial vehicles entering the zone during particular periods, with a 90% discount for residents and exemption for buses, taxis and disabled individuals) envisages that the penalty will be around per instance.
while the current level of accuracy would not support an account-based charging system (for which a vehicle would have to be detected in order to be charged), it is sufficient for the enforcement of the current pre-pay system; individuals must pay the charge without knowing whether they have been detected, and even the reduced penalty charge (if paid within 14 days) is more than six times the daily charge.
Given the speed of processing and sufficient cameras it is possible to develop highly granular, time-specific and dynamic charging, e.g. different charges at various times of the day, higher charges when pollution reaches particular levels.