Plug-in hybrids cost over £450 a year more to run than manufacturers’ claim

New analysis from the Energy and Climate Intelligence Unit (ECIU) has found that drivers of the UK’s top-selling plug-in hybrid vehicles (PHEV) are likely to be spending almost twice as much money to fuel their cars than their manufacturers have led them to believe – over £450 a year.
 
Based on their manufacturers’ claims about their fuel efficiency, the UK’s best-selling PHEVs should cost, on average, around £530 a year for petrol and electricity. But based on research by Transport & Environment which has found that PHEVs consume 490% as much fuel as their manufacturers claim, [1] ECIU has found in real life these costs jump to £985 a year, due to petrol being more expensive per mile than electricity.
 
This disparity between claimed and real-world fuelling costs has a knock-on effect on a PHEV’s total costs of ownership (its purchase price, fuelling costs, insurance, tax and servicing). The analysis has found that, over the course of their lifetimes, the UK’s best selling PHEVs actually cost £81 a year more to own and run than a regular petrol car. And compared to an equivalent EV, these PHEVs’ total costs of ownership are almost £1000 higher each year.
 
These findings come following the Government’s decision in 2025 to weaken its Zero Emission Vehicle Mandate (a policy to encourage the shift away from polluting vehicles) in a way that that could encourage manufacturers to try to sell more PHEVs, and fewer EVs that have no exhaust emissions. [3] Flexibilities in the policy lobbied for by some manufacturers allow targets to be met through a combination of the sale of EVs and the sale of lower-emission petrol and diesel cars. Since impressively low claims are made about the CO2 emissions of PHEVs, they offer an attractive potential source of the credits a manufacturer needs to hit its EV sales targets. But since these claims have been proven to be unrealistically low, it means the Government’s EV sales targets can be met, in part, through the sale of vehicles that have real-world CO2 emissions that are not dissimilar from a regular petrol car.

Colin Walker, Transport Analyst at the Energy and Climate Intelligence Unit, said: “This increasingly looks like a scandal with echoes of ‘dieselgate’. The industry’s successful lobbying of government will encourage the sale of hybrids and keep the nation’s driving bills high. Expanding the pool of hybrids on the road will leave the second hand market, where most of us buy our cars, awash with vehicles that are much more expensive to run and own than EVs. Some families will be left simply unable to make the switch to cheaper and cleaner electric driving.
 
“Drivers already pay a ‘petrol premium’ of hundreds, even thousands, of pounds year to run a petrol car rather than an EV, but it’s clear the premium to drive a plug-in hybrid is almost as high.

“Even with the introduction of a 3p a mile tax on EVs, they will remain cheaper to own and drive. But with the prospect of more families and businesses left paying more to drive hybrids than EVs, that’s a real knock to the nation’s productivity. We’re spending more to drive than we need to and so less in other parts of the economy.”

ENDS

Notes to editors:

1. T&E: https://www.transportenvironment.org/articles/smoke-screen-the-growing-phev-emissions-scandal
 
2. the UK’s 10 best-selling PHEVs in 2025 were identified, and their fuelling costs calculated using a) their claimed fuel consumption levels and b) their real world fuel consumption levels, based on analysis by Transport & Environment of data from the European Commission. The difference was then calculated. These figures were then used to calculate the real-world annual total costs of ownership of these vehicles, together with their sticker prices, tax, insurance and servicing costs. These were then compared with the annual TCO figures for these vehicles’ petrol and electric equivalents.
 
3. https://www.gov.uk/government/consultations/phasing-out-sales-of-new-petrol-and-diesel-cars-from-2030-and-supporting-the-zev-transition/outcome/phasing-out-sales-of-new-petrol-and-diesel-cars-from-2030-and-supporting-the-zev-transition-summary-of-responses-and-joint-government-response

For more information or for interview requests:

George Smeeton, Head of Communications, ECIU, Tel: 07894 571 153, email: george.smeeton@eciu.net