The cost of charging an electric car at the kerbside fell by 12% during June, according to a new report by the AA.

It found that the average peak rate for using a slow charge point (up to 8kW) – typically found in residential areas – fell from 67p per kWh in May to 59p per kWh in June.

Nonetheless, powering an electric car can be typically more expensive than a petrol equivalent, the report suggests.

Charging a Vauxhall Corsa Electric using slow chargers at peak times gives it a running cost of 13.33p per mile. A 1.2-litre petrol Corsa cost 12.85p per mile, having benefited from a 3.4p-per-litre fall in the average cost of the fuel. 

However, using slow and ultra-rapid chargers at off-peak times yielded lower running costs than the petrol car, at 9.49p per mile and 11.53 per mile respectively. 

The other peak-priced rates remained the same as in May. Fast (9-49kW) and rapid (50-149kW) chargers averaged 79p per kWh at peak times, giving a cost per mile of 17.85p. Off peak, their rates averaged 75p per kWh, costing 16.95p per mile. 

On-peak ultra-rapid chargers were cheaper, at an average of 59p per kWh. That yields an average cost per mile of 13.33p.

Flat-rate chargers proved more competitive. The cost of charging at home averaged 24p per kWh, the same as in May. This yields a cost per mile of 5.42p, less than half the cost of the petrol Corsa. 

Flat rates for slow and fast (9-49kW) chargers fell by 1p, to 51p per kWh and 56p per kWh respectively. This meant slow charging averaged 11.53p per kWh, while fast charging averaged 12.66p per kWh.

“Considering 40% of households don’t have their own driveway or parking space, keeping residential charging prices low is vital to help prospective EV owners make the switch,” said Jack Cousens, head of roads policy for the AA.

Cousens called for the new Labour government to enact “easy wins” on the cost of charging, such as cutting VAT and increasing support for local government in areas with a shortfall of chargers.