The tariff, 1 Year Fix and Drive, gives customers up to 2,000 kWh of electricity free per year when they charge their car overnight (midnight to 7am).

The energy giant says it’s the equivalent of 8,000 miles free a year, based on rated consumption of a TESLA Model 3 Standard Range Plus.

The tariff is available to both new and existing customers, and doesn’t have an exit fee. To be able to sign up to Fix and Drive tariff, customers must own or lease an EV and may be required to show their V5C certificate to prove ownership. Customers will also need a smart meter to purchase the tariff so SSE can track energy usage overnight.

SSE said that when a customer signs up to the tariff, all electricity will be matched with 100 per cent renewable electricity.

Stephen Forbes, managing director of SSE Energy Services, said: “We know that the majority of EV owners charge their car at home as this is the easiest way to keep their battery topped up. Here at SSE, we want to make using electric cars even more convenient, which is why our new 1 Year Fix and Drive tariff allows customers to charge their car at home overnight for free.

“We hope this new tariff will help the growing number of electric vehicle owners across the country reduce their carbon footprint and take control of their bills, too.”

The government is currently consulting on introducing “green” number plates for electric vehicles. The plates would make electric cars easily identifiable if local authorities introduced incentives to promote zero emission vehicles, such as allowing these drivers to use bus lanes and to pay less for parking.

SSE announced last month that it has agreed to sell its household energy business to Ovo Energy for £500m.