Energy price cap increase: what it means for electric car running costs

The cost of charging an electric car at home will go up from 1 January 2024, following Ofgem’s announcement that the energy price cap will rise by 5%.

The price cap, which applies to variable energy tariffs and limits the price of a single unit of energy, had gone down in October this year. However, it has now has been revised upwards for the forthcoming quarter, with rising wholesale energy costs and market instability blamed.

EV drivers who charge solely at home and aren’t on a fixed tariff will experience a slight increase in their car’s fuel costs of around £30 a year, based on the energy efficiency data of all electric cars we’ve tested.

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How the cost of charging an EV from home will change

With a new typical unit rate for electricity of 29p/kWh (up from 27.35p/kWh), there will be small increases in running costs for electric cars when charged at home.

The table below shows the annual costs of charging an EV at home based on the current and new price cap, along with average annual petrol and diesel running costs, for comparison.

Head to our energy supplier switching guide to find out more about switching to the best fixed-price tariff, and those geared towards EV owners.

Why EV efficiency matters

As with petrol and diesel cars, average fuel economy doesn’t tell the whole story – EV models can vary greatly in terms of their energy consumption, with weight, performance, aerodynamics and thermal efficiency all having an effect.

All our car reviews feature lab-tested efficiency and you can view the reviews ordered by running cost. Our lab tests include a motorway cycle designed to better replicate real-world driving conditions than official assessments.

Find out more about the ins and outs of domestic charging, in our guide to charging an EV at home.

Most efficient EV: Hyundai Ioniq 6

Currently sitting as the most efficient electric car overall is the Hyundai Ioniq 6.

Despite a healthy 229hp and a sizeable overall footprint, its eye-catching coupe styling makes it one of the most aerodynamic EVs available. That, and decent overall efficiency, will see owners facing just a £22 rise in annual running costs due to the price cap, with an average fuel bill of £502 (based on 7,050 miles annually).

That’s exactly half what you’d expect to pay to run the least efficient EV we’ve tested to date.

The Mercedes Benz EQV – which admittedly is an enormous and hugely practical large MPV – will have an average annual energy cost of £1,004 – a £45 rise over this quarter.

Find out how other EVs score for efficiency in our guide to the cost of charging an electric car.

Electric vs diesel and petrol

While the new kWh unit price cap is still low enough for EV drivers to charge at home and save money compared to running a petrol or diesel car, the same can’t be said for drivers reliant on public chargers, which are often two to three times more expensive.

Using our extensive efficiency data, the table below shows the price at which charging an electric car (in pence per kWh) becomes more expensive than filling a comparable petrol or diesel.

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