The Euro 6e-bis standard puts hybrid electric cars under the spotlight

Regulations on fuel consumption and polluting gas emissions are constantly changing to adapt to the realities of legislation in European countries. Manufacturers must therefore comply with what these laws stipulate and adapt their vehicles until they meet them. The latest regulation is Euro 6, although it has had two updates, called Euro 6d and Euro 6e.

The latest evolution of the Euro 6 standard sets new limits for vehicles driving in Europe, including plug-in hybrid cars. This new standard came into force on 1 January 2026, so all manufacturers have had to re-certify all their models to comply with the new standard.

Earlier versions of the Euro 6 standard focused on reducing the regulated polluting emissions and incorporated Real Driving Emissions tests, while this new evolution adds specific requirements for plug-in hybrid cars, related to the certification of their CO₂ emissions, the utility factor and their use.

Changes in measurements

The problem is that laboratory tests produced emissions and consumption figures far lower than those seen in real traffic conditions. The tests assumed that drivers would use the vehicle in electric mode, something that does not happen in practice. These erroneous figures also cause problems for tax enforcement, since exemptions are applied that are not real and lead to discrepancies between the taxes levied and those that should apply.

This new regulation Euro 6e-bis makes homologation requirements more demanding, incorporates advanced On-Board Monitoring (OBM) systems, strengthens Real Driving Emissions (RDE) tests and adjusts the criteria applied to hybrid and plug-in hybrid vehicles. In this way, more realistic test conditions are achieved, better aligning laboratory tests with real-world driving.

As a result, the average consumption and emissions values of hybrid and plug-in hybrid cars have risen considerably compared with previous measurements. For example, a Ford Kuga PHEV has gone from being homologated with a consumption of 0.9 l/100 km and emissions of 20 g/km CO₂ to 2.7 l/100 km and 52 g/km CO₂. The change is very visible and brings many consequences.

Cars that already carry an ECO label are exempt from these changes, which only apply to new vehicles and those that have had to be re-certified under the new standard. If any hybrid or plug-in hybrid vehicle exceeds 120 g/km, it will be subject to the registration tax, which will affect the selling price and other matters that will reduce the competitiveness of these models.