Interested in this kind of news? Receive them directly in your inbox. Delivered once a week. Sign Up The discrepancy between what cars emit in their official testing – done in laboratories – and what they emit in real-world driving conditions can be as high as 1000% for air pollutants and 50% for CO2. It means that emissions from cars in cities are much higher than expected, resulting in cities with air pollution that is killing thousands of people a year, and leaving drivers with an additional €500 bill for additional fuel. Now the mayors of London and Paris, Sadiq Khan and Anne Hidalgo (pictured), have agreed to monitor cars under The Real Urban Emissions initiative (TRUE), a new partnership set up with specialist input from T&E, the International Council for Clean Transportation and the FIA Foundation. It was launched last month at an event involving the C40 initiative of cities with air pollution problems, some of which also want to develop real-world emissions monitoring systems. The idea is to monitor the emissions of almost all cars on London’s and Paris’s streets via a technique known as remote sensing, and compile a database which will be available through a new vehicle emissions scoring website, the Clean Vehicle Checker. Testing will begin soon, and the first information will be available on the website when it launches in autumn. The information will only be a guide for car buyers, but with rules on high-polluting cars getting stricter in London, Paris and other cities, the lower-emitting cars will gradually gain more advantages. For example, London has just announced plans for an ultra-low emissions zone to come into effect in April 2019, with the most polluting cars facing a daily charge of around €14.50 to enter the city centre. The mayor of London Sadiq Khan said: ‘The toxicity of the air in London and many other big cities is an outrage, and schemes of the type we are introducing in London and Paris have the potential to make a massive difference to the quality of the air we all breathe.’ He added that the scheme will deliver the ‘robust and independent data needed to put an end to the smoke and mirrors around vehicle emissions.’ T&E clean vehicles director Greg Archer said: ‘Real-world testing can provide consumers with reliable information about both fuel economy and polluting emissions, as T&E’s work with Peugeot-Citroën has shown. Remote sensing provides an innovative and hopefully effective way of detecting the most polluting vehicles on the road.’ The FIA is the governing body for world motor sport and the federation of the world’s leading motoring organisations. The FIA Foundation is an independent UK-registered charity which supports an international programme of activities promoting road safety, the environment and sustainable mobility, as well as funding motor sport safety research.