How EVs could be part of answer to UK’s fuel reserve worries

The Iran war has sent petrol and diesel prices to their highest levels in years, sparked warnings of fuel rationing across Europe and triggered calls for Britain to drill more North Sea oil and gas. But analysis suggests the UK is looking for solutions in the wrong places – and that one of them is sitting on people’s driveways or parked in the street.
If more drivers switched electric vehicles, Britain would sharply reduce its petrol and diesel consumption, with every car charged from the grid rather than the pump extending the country’s fuel reserves – and experts say the potential impact goes far beyond that.
Before the war, the UK had about three weeks’ worth of car fuel in reserve: 21 days of petrol and 22 days of diesel, according to official data analysed by the policy consultancy Mandala Partners. That reserve could reach an extra seven days of petrol if Britain had as many electric cars per head as Norway, the world leader. Nearly 32% of all cars on Norwegian roads are fully electric, compared with 5.4% in Britain.
Even now, Britain’s existing electric and hybrid cars are saving about two days’ worth of fuel, the researchers estimated. That figure underlines the size of the opportunity at a time when Shell’s chief executive, Wael Sawan, said on Wednesday that Europe could face fuel shortages as soon as April if the strait of Hormuz, the key shipping lane in the Gulf, remained closed.
The gap between the countries is doubly striking because Norway presents bigger challenges for EV drivers. It is the longest country in Europe, with freezing winters that can sap battery life. But any lingering range anxiety has been quelled by a dense, state-backed and commercial charging network. Britain, by comparison, has fewer such excuses, the researchers said.
“Those arguing on energy security grounds for new exploration and to cut taxes on domestic oil and gas production, ought also to advocate for electrification,” Mandala Partners wrote.
More ambitious still is that Britain’s electric car fleet could go further than simply replacing petrol usage, and become an active buffer against future energy shocks by storing and resharing energy.
Every electric car, when plugged in and not being used, is a battery on wheels – and most sit idle for 95% of the time, estimates the RAC Foundation. With the right type of charging points and inverters fitted to cars, that stored energy could flow back into the power grid when people are using more electricity or when supply runs short.
The technology, known as vehicle-to-grid, “turns your car into a virtual power plant”, said Alex Schoch, Octopus Energy’s director of electrification. An electric car usually holds about 40 kilowatt hours of power, enough for an average UK home for several days. “It lets EVs not just charge from the grid, but send energy back, powering homes, balancing the grid, or even supporting your neighbour’s kettle,” added Schoch.
In an energy supply crisis like this one, that excess electricity scattered across the country could make a big difference, proponents say. Rather than drawing on gas-fired power stations to meet demand spikes – the fuel behind much of Europe’s current price surge – the grid could instead draw on millions of car batteries.
The motivation for drivers is that they can make money from it. Octopus claims that customers on its main vehicle-to-grid tariff save about £620 a year on charging costs by selling back to the grid when demand is high and buying it back cheaply overnight.
Nonetheless, it has not yet caught on. Fewer than 100 people currently use two-way charging on that tariff, Schoch said, although more than 10,000 have expressed an interest.
One barrier is tax policy. EV owners pay tax on electricity when filling their car battery. Then, after selling it back to the grid, they must pay the same tax again when refilling. Germany and the Netherlands have passed laws to prevent this but Britain has not. Schoch called it “the single biggest thing” holding the technology back.
The other is simply that the hardware is not yet in place. While many electric cars – such as Volkswagen’s ID range, the Nissan Leaf and Chinese BYD models – are already capable of two-way charging, other carmakers have not switched on the feature en masse. Schoch believes that will change within three to four years as demand grows.
The energy regulator Ofgem has suggested that if half of the expected 11m EVs on UK roads by 2030 were capable of two-way charging, they could send 16 gigawatts of power back to the grid each day. That is almost half the output of Britain’s gas-power station fleet.
EVs would effectively be “a resilient, distributed virtual battery that could be a core part of absorbing price shocks”, Schoch said.
All of that requires filling UK roads with electric cars, but that effort is stalling. Battery electric cars’ share of sales in February fell by 1 percentage point compared with the year before, amid a broader chill in the industry. Ford, Volkswagen and the Vauxhall-owned Stellantis have written down tens of billions of pounds worth of investments in EVs in favour of more profitable combustion engines as they face slumping sales.
While there has been a recent spike of interest in EVs since the outbreak of the Iran war, Ian Plummer, the chief customer officer at the listings site Autotrader, said this month that previous peaks – such as during the energy crisis of 2022 – had not “led to sustained increases in electric purchases”.
The UK’s zero-emission vehicle mandate, meanwhile, which requires all new car sales to be electric by 2035, is also under pressure from industry lobbying. At a moment when the case for electrification is stronger than ever, the pace of its rollout remains far from certain.