Gwyn TophamSat 10 Mar 2018 08.01 GMT
Some new diesel models emit 12 times legal limit, while others ‘are the cleanest cars on the road’
False emissions ratings for cars based on lab tests have cost the UK more than £2bn a year in lost tax revenue, according to the Green party.
With CO2 emissions exceeding official measures by an average of 42%, millions of vehicles have been placed in tax bands that do not reflect their true levels of pollution, according to new research published on Saturday.
Since 2001, UK vehicle excise duty has been based on carbon emissions. Cars registered before April 2017 and producing less than 100g of CO2 per km are exempt, with the rate rising to £535 for the most polluting cars.
Analysis for the Green party in Europe shows that car taxes would have been more than €10bn higher across 11 EU countries last year, with the UK one of the main losers due to its large car fleet and graded tax system.
Sign up to the daily Business Today email or follow Guardian Business on Twitter at @BusinessDesk The report estimated a loss of more than £2bn in the UK in 2016, based only on new vehicles registered since 2010, which make up around half of the cars now on the road.