Electric vehicles are getting greener due to the recent switch from coal to renewables, and now create half the CO2 of the cleanest conventional and hybrid cars on the road, according to a new report.

Writing in Electric Insights Quarterly, Dr Iain Staffell of Imperial College London said: “Producing the electricity to charge a Tesla Model S back in 2012 would have created 124g per km driven – the same as a 180 horsepower Range Rover.

“Nowadays that has halved to 74g per km in winter and 41g per km in summer. Smaller cars like the Nissan Leaf and BMW i3 can be charged for less than half the CO2 of the cleanest non-electric car on the market – the Toyota Prius hybrid.”

He said the calculation is complex because it depends on what time of day or night a vehicle is charged, and which power stations increase output to meet the additional demand.

The number of plug-in vehicles on Britain’s roads recently topped 100,000. Pure electric and plug-in hybrid numbers have grown 30-fold in four years, and now represent 1.8% of new car registrations.