The UK needs a sixfold increase in the number of electric vehicle charging points by 2020 to provide adequate infrastructure for green motorists, new research has found.

It estimates there will be more than one million EVs on UK roads within two years, requiring 100,000 charging points. Currently there are just 16,500, according to the report from data company Emu Analytics.

Currently only 3 per cent of supermarkets have a charging point, the research found. Asda has the best coverage, with chargers at 19 per cent of its stores, while Tesco has the worst, with chargers at just 0.4 per cent.

Rapid chargers, which can fill 85 per cent of an EV’s battery in half an hour, are even more scarce. Lidl has the highest number of rapid chargers at just 11.

Across the UK there are only 1,500 rapid chargers, with space to charge 3,400 vehicles. By comparison there are 9,000 petrol stations, each with multiple pumps which can fill a tank in minutes.

A charging network is “critical” to the expansion of EVs because the majority have a maximum range of between 100 and 200 miles, with actual range often being less, the reports authors said.

The government has committed £440m to delivering charging infrastructure and has also mandated twenty-two local authorities to develop plans this year for tackling poor air quality and to look at enforcing Clean Air Zones.

The Plug-In Car Grant, a subsidy for EV purchases, has coincided with a surge in EV registrations, from less than 2,000 In the first quarter of 2014 to more than 14,000 in the third quarter of 2017, the research found.

The report highlights plummeting diesel sales as a potential driver of further rapid expansion of the EV market. New diesel sales crashed 20 per cent in the final six months of last year, as the cars have been linked to high levels of air pollution and many consumers have been left confused about future taxes and regulations on the cars.

The existing fleet of diesel cars in the UK will need to be replaced by a green alternative, the researchers said.