Home Charging Saves EV Drivers £1,240 a Year Over Diesel, Ofgem Cap Shows

• Ofgem’s price cap from 1 October to 31 December 2026 sets electricity at 26.32p a kWh with no VAT, which works out at about 7.8p a mile for an average electric car.
• Against the RAC’s 20p a mile for a diesel car, charging at home over 10,000 miles costs about £780 against £2,020, a gap of roughly £1,240.
• Public rapid charging at Zapmap’s 77p a kWh average works out at 23p a mile, or £2,300 over 10,000 miles, dearer than diesel.

Charging an electric car at home on the standard energy price cap now costs about 7.8p a mile. A diesel car costs 20p a mile at today’s record pump prices. Over a typical 10,000 miles a year, that is about £780 against £2,020, a gap of roughly £1,240 in the electric driver’s favour.

The electricity side of that sum comes from Ofgem. Its price cap, which applies from 1 October to 31 December 2026, sets the average unit rate for a household on a default tariff paying by Direct Debit at 26.32p per kWh. The daily standing charge is 54.83p. From 1 October the Government has also removed VAT from household electricity bills, a change that runs to 31 March 2027, and the cap figures already include it.

The per-mile conversion uses Zapmap, whose August 2026 Price Index assumes an average electric car costs 16p a mile at 54p a kWh. That implies roughly 0.3 kWh per mile. The diesel figure is the RAC’s: 20p a mile for a 45mpg car at the record 200.01p a litre it reported on 2 October 2026. Any figure below marked as our calculation is built from those published numbers.

The Catch: Public Rapid Chargers Now Cost More Per Mile Than Diesel

The home saving only holds for drivers who can plug in at home. Zapmap’s Price Index, updated on 4 September 2026 with August data, puts the average pay-as-you-go price, based on how much power each network delivers, on the UK public network at 54p per kWh for standard and standard plus chargers (3kW up to 49kW) and 77p per kWh for rapid and ultra-rapid chargers (50kW and above).

Zapmap converts those prices to 16p a mile on standard chargers and 23p a mile on rapid chargers. Over 10,000 miles that is £1,600 and £2,300. Against the RAC’s £2,020 for diesel, a driver who relied entirely on rapid chargers at the average price would pay about £280 a year more than a diesel driver, while one using standard public chargers would pay about £420 less.

Zapmap also reports that prices are rising. The average standard charger price is up around 6 percent on a year earlier, and the average rapid price is up around 1 percent. Home electricity looks calmer: Ofgem says electricity bills under the cap remain broadly stable for the new quarter, helped by the VAT removal.

Rates differ by network. Zapmap lists Sainsbury’s Smart Charge at 72p a kWh and Believ at 66p. At Tesla Supercharger sites open to all drivers the average is 63p. Using the same 0.3 kWh per mile, those work out at about 21p, 20p and 19p a mile (our calculations), so even the cheapest of them sits close to the 20p a mile for diesel.

What the VAT cut is worth to an electric driver

Ofgem says the removal of VAT from electricity bills is reflected in the October cap. For a typical household using gas and electricity, the regulator said the total would have been around £45 higher without it. Gas keeps its 5 percent VAT.

For a driver who charges at home, the effect is easy to size. Adding 5 percent VAT back to 26.32p would give about 27.64p per kWh, so the cut is worth around 1.32p per kWh. An average electric car covering 10,000 miles uses about 2,960 kWh at 0.296 kWh a mile, which makes the VAT removal worth about £39 a year to that driver (our calculation).

Ofgem also warns that the new rates cannot be compared directly with earlier quarters, as the VAT change distorts the comparison. It adds that households which do not use gas will see a rise of less than 1 percent in the new cap. The typical bill for a household using both fuels rises 4 percent, or £60, to £1,723 a year.

How the sums work out at home

At the capped rate of 26.32p per kWh, the 0.296 kWh a mile used by an average electric car costs about 7.8p a mile. Over 10,000 miles that is about 2,960 kWh and £779 (our calculation, leaving out the standing charge, which a household pays whether it owns an electric car or not).

Set against the 20.2p a mile implied by the RAC’s diesel figure, the gap is about £1,241 a year, which is where the headline number comes from. A petrol car at 45mpg and the RAC’s 174.71p a litre costs about 17.7p a mile, or £1,765 over 10,000 miles, so the home-charging saving against petrol is about £986 (our calculation).

These are national averages. Ofgem’s cap varies by region, and the unit rate on the day depends on the supplier, the meter and the payment method. About 35 percent of households, around 11 million, are on fixed tariffs and are not on the capped rate at all.

Can You Avoid the Dearer Charges? Steps That Protect the Saving

The spread between the cheapest and dearest way to charge is far bigger than the spread between most petrol and diesel pumps. Zapmap’s own example drivers show how much the choice is worth.

Charge at home as much as you can. Zapmap models three drivers. John and Rosa charge mostly at home on an EV tariff averaging 8.6p a kWh and save £1,030 a year against refuelling a petrol or diesel equivalent. Michael and Marie charge about half at home, topping up at supermarkets and motorway services, and save £590. Kris relies entirely on public charging and, according to Zapmap, does not save on charging compared with refuelling the equivalent petrol car. He still gains on car tax, servicing and maintenance, Zapmap says.

Look at an EV or time-of-use tariff. Zapmap’s profiles use an average of 8.6p a kWh. At that rate the 2,960 kWh for 10,000 miles costs about £255, or roughly 2.5p a mile (our calculation), which is £524 less than the standard capped rate of 26.32p. Ofgem notes that many suppliers offer cheaper electricity to smart meter customers for power used out of peak times, so a driver who charges overnight can often use that.

Compare fixed deals. Ofgem says fixed tariffs are available at £100 or more below the October cap for a typical household, and that the VAT removal benefits customers already on fixed tariffs, with the discount applied automatically by suppliers. Fixed deals are worth checking if you are on a default tariff, though the saving shown is for the whole household bill, not for charging alone.

Avoid pay-as-you-go rapid charging where you can. The average rapid price of 77p a kWh costs about 23p a mile, more than the 20p a mile for diesel. Compare prices on the network before you plug in. Sites at 63p to 66p a kWh bring the cost to roughly 19p to 20p a mile (our calculations), and standard chargers at an average of 54p come to 16p a mile. Many networks also offer membership or promotional deals that cut the pay-as-you-go price, a point Zapmap makes itself.

Watch the dates. Ofgem’s VAT removal on electricity runs from 1 October 2026 to 31 March 2027. The regulator will announce the next cap, covering 1 January to 31 March 2027, on 25 November 2026. The cap for 1 April to 30 June 2027 follows on 23 February 2027. Check each announcement, as the unit rate you pay in the new year could differ from the 26.32p quoted above.

For a household that can charge at home on the standard cap, the sums above put an electric car at roughly 7.8p a mile against 20p for diesel. For one that cannot, the answer depends on which charger and which network the driver uses.

Sources:

• Ofgem: Changes to energy price cap between 1 October and 31 December 2026
• Ofgem: Energy price cap will rise by 4% from October 2026
• Zapmap Price Index (updated 4 September 2026)
• RAC Media Centre: Diesel tops £2 a litre for first time ever (2 October 2026)