Plug-in hybrids pollute like petrol cars – and leave drivers paying more

Even in electric mode, PHEVs still burn fuel and emit 68g of CO₂/km, on average, and their hidden fuel consumption costs the average PHEV driver £650 more a year than running a battery electric vehicle (BEV).

UK sales of plug‑in hybrids (PHEVs) soared 56% in September compared with last year, according to the latest Society of Motor Manufacturers. But new analysis from T&E UK reveals these vehicles emit five times more CO₂ than claimed and cost the average driver over £650 more a year to run, making them less cost‑effective than a fully electric car.

’’Plug-in hybrids look green on paper, but the reality is they pollute far more and cost hundreds of pounds extra each year to run. It’s unacceptable that outdated official tests continue to mislead consumers - drivers deserve to know what they’re really buying.’’ Tim Dexter, UK Vehicles Policy Manager, said.

New evidence from over 127,000 real‑world PHEVs reveals they emit just 19% less CO₂ per kilometre, on average, than petrol and diesel cars, a stark contrast to industry claims. When driven on the road, their emissions are almost five times higher than official figures which assumes frequent battery charging. The gap is also getting worse, increasing from 3.5 times in 2021.

To ensure that consumers aren’t ‘duped’ by the false official CO₂ emissions of PHEVs, it is essential that the government updates the type approval of PHEVs to reflect real-world CO₂ figures before implementing changes to the ZEV mandate. Otherwise there could be a large increase in PHEV sales which fail to deliver the expected CO₂ savings on the road damaging the UK’s ability to meet climate targets.

This decision does not just impact emissions targets, it hits consumers directly in their pockets. Recent analysis shows refuelling a PHEV costs drivers on average over £650 more a year than running a battery electric vehicle (BEV). Many consumers, misled by the ‘low emission’ image of PHEVs portrayed by carmakers, will be left paying higher fuel costs while unknowingly emitting far more CO₂ than thought.

Put simply, choosing a medium‑range PHEV, like the VW Tiguan, over a BEV, such as the Kia EV3, leaves drivers about £1,500 worse off every year due to higher upfront prices and more fuel use. Yet despite higher purchase prices and running costs, carmakers still push PHEVs as the sensible choice.

‘‘Until official PHEV emissions and taxes reflect real‑world performance, plug‑in hybrids will keep polluting more than promised — and Britain’s climate targets will take the hit. PHEVs are one of the biggest cons in automotive history, costing drivers far more than they realise. The real smart and affordable choice is to go all‑in on electric — and with more budget‑friendly BEVs hitting the market next year, there’s no reason to choose anything else.’’ Tim Dexter added.