Instead of banning older diesel vehicles in certain zones throughout German cities as was recently proposed, European Transport Commissioner Violeta Bulc believes that charging a toll to each driver based on their vehicle’s emissions would better combat air pollution.

"City toll systems can be an effective tool to clean up the air in cities," while also avoiding "very frustrating" vehicle bans, Bulc said.

One potential solution, according to Bulc, could be an electronic levy system that would allow national governments to impose “dynamic tariffs, for example depending on levels of harmful emissions or the time of day."

Although systems to track cars would likely be expensive to initiate, Bulc believes that they "…would pay off quite quickly both from a financial perspective and in terms of the environment and protecting health" of city residents.

A similar toll scheme has already been introduced in London where the oldest, most polluting vehicles (built before 2006) are charged 10 pounds (11.18 euros or $13.87) per day in addition to a general 11.50-pound “congestion charge” for entering the city.