Testing carried out at the company’s facility in Los Angeles has found that driving a hybrid passenger car with the air conditioning turned fully on reduces MPG by an average of 6.1%– almost double the average reduction recorded in petrol engine cars which amounted to 3.8%. In comparison, the average MPG in diesel cars was found to be reduced by 4.6%.

The data, compiled by comparing over 100 passenger cars, also highlights the impact of using air conditioning on fuel economy during motorway and city driving. The tests found that hybrid models perform worst in both conditions, with air conditioning on average reducing MPG by as much as 9.3%when driven in the city and 2.8%on the motorway.

Air conditioning was found to have the least impact on petrol engine cars in both test scenarios, as MPG was reduced by 5.1% during the city drive and 2.7% on the motorway drive. Again diesel engines were found to be somewhere in the middle, with results showing an average reduction in MPG of 6.4% in the city, compared to on a motorway which amounted to a reduction of 3.3%.

Commenting on the findings, Nick Molden, founder and CEO of Emissions Analytics, said: ‘While these results were based on tests conducted in the United States where the climate tends to be warmer and there is therefore larger requirement for air conditioning, our findings can still be applied by consumers in the UK when looking for their next car.’