Plug-in hybrids face stricter emission tests in 2025 as misleading efficiency figures are targeted
More realistic emissions testing could see substantial tax increases for PHEV drivers
Plug-in hybrid cars will be subjected to more stringent emissions tests in 2025 to better represent real-world use cycles, Auto Express can confirm. It’s thought the changes could have significant implications for company car drivers, with some models expected to see big jumps in tax bands, which are based on CO2 emissions.
Existing Euro 6e emission standards will be superseded by so-called Euro 6e-bis tests, applicable to all new models launched from 1 January 2025. This will then be updated at the end of the year (31 December) to include all cars on sale, meaning existing models will have to be retested in order to comply.
Previously, the emissions tests were conducted over a simulated distance of 800km (497 miles), but Euro 6e-bis ups this to 2,200km (1,367 miles). To illustrate the effect this has on a PHEV’s emissions and fuel consumption in real world driving, the International Council on Clean Transport (ICCT) analysed the performance of a BMW X1 xDrive25e under the revised conditions.
The ICCT said: “Over the past several years, it has become evident that the currently used UF curve does not reflect the real usage of PHEVs resulting in unrepresentatively low official CO2 emission values.
“This leads to an excessive gap between the real-world fuel consumption and the official value determined during type-approval.”
The new parameters saw the X1’s emissions rise from around 45g/km, to 96g/km. The X1 has a current Benefit-in-Kind company car tax banding of eight per cent, but the 6e-bis tests would see this number jump to 24 per cent – comparable with the most efficient pure petrol models.
A further advancement in emissions standards is expected in 2027, when ‘Euro 6e-bis-FCM’ comes into force. Under these circumstances, tested over a total distance of 4,260km (2,647 miles), the same BMW is said to emit around 122g/km.
As it stands, only cars bought brand new will be affected by the updated emissions standards; there are no plans to backdate the bandings for existing company car users. This is in contrast to the proposed introduction of VED road tax for electric car drivers due later this year, which will be applicable to both new and existing electric vehicles.
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