Analysis of DVLA data by the RAC Foundation shows that at the end of Q2 2015 there were 35,241 vehicles on the road in the UK that were eligible for the Government’s plug-in car and van grants, a rise of 19% on the Q1 2015 figure of 29,673.

The Mitsubishi Outlander Plug-in Hybrid remained the most popular ultra-low emission vehicle, with a total of 12,066 licensed at the end of Q2 2015, compared with 9,773 at the end of Q1 2015 – a 23% increase.

In second place was the Nissan LEAF, with 9,310 units on the roads in Q2 2015, a 13% increase on the 8,274 figure three months earlier.

Third in the list is the BMW i3 (2,484, up 14%).

Steve Gooding, director of the RAC Foundation, said: “The success of the Outlander looks to be down to three things: a high-profile advertising campaign, good range, and probably most importantly competitive pricing which makes it as affordable to buy as the diesel equivalent. 

“But that price is dependent on the government grant. Ultimately all ultra-green cars will have to stack up commercially when the grants are withdrawn. What ministers must ensure is that both consumers and manufacturers have a clear idea of when and how the scheme will come to an end.”