Plugin Hybrid Cars Pollute 200–400% More Than Official Ratings

Real-world CO2 emissions of plugin hybrid cars (PHEVs) are on average 2–4 times higher than official values, which for most plugin hybrids are less than 50g/km on paper. Almost 1 million of them will have been sold in the EU in 2021 alone — carmakers are pushing their sales because their unrealistically low official CO2 emissions allow them to easily meet their CO2 targets. Yet PHEVs do not deliver the expected CO2 savings on the road due to both their design and lack of incentives to charge, undermining the car CO2 regulation and reducing the sales of truly zero emission cars.

To address the problem, the European Commission is planning to reform the way PHEV CO2 emissions are calculated, ie update utility factors (UFs): the currently unrealistic assumptions on the share of electric kilometers driven by PHEVs which underestimate official PHEV CO2 values. This review is welcome and is urgently needed as the credibility of Europe car climate policy is at risk.

The real-world data on plugin hybrid cars use will soon be available from on-board fuel consumption meters (OBFCM) fitted to all cars sold in the EU from the start of 2021. Yet, the Commission is not planning to use that data fully until 2030, allowing polluting PHEVs to be sold for another decade. Basing UFs on a very limited data set in 2025-2030 risks, once again, underestimating the PHEVs real CO2 emissions.

T&E understands that the reason for delaying to 2030 is that the Commission is concerned over real world data availability from OFCM, as collection during periodic technical inspections (PTI) does not begin until 2023. But the reality is that only 1.5% of records (14,000 ) need to be collected by car makers in 2021 from the close to a million PHEV expected to be sold this year for the Commission to have more representative data than the dataset they plan to use from 2025. It is highly likely that such a small threshold will be achieved, and therefore there is no reason not to base UF on real world data as soon as possible and no later than 2025. Delaying will not only car CO2 reduction goals, but will lock Europe’s carmakers sub-optimal technology at the time of the global race to electrification.

Alongside implementing real-world UFs as soon as possible, the Commission also needs to ensure that UFs remain representative of plugin hybrid car use. The Commissions should therefore update UFs on an annual basis in line with the frequency of OFCM data collection. To reward manufacturers which sell efficient PHEVs and encourage their customers to charge, the Commission should implement manufacturer-specific UFs from 2027 when over 1.5 million PTI records will be available.

T&E recommends that the Commission:

1. Introduces real world utility factors based on OFCM data for the calculation of PHEV CO2 emissions and for compliance with fleet CO2 standards no later than 2025.

2. Updates utility factors on an annual basis in line with the frequency with which the Commission will receive updated OFCM data from the EU fleet.

3. From 2027 introduces manufacturer specific utility factors, to reward those carmakers which improve the performance of their PHEVs and encourage their customers to charge.

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Originally Posted on Transport & Environment.


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