24 Nov 20

OEMs dispute T&E claims that PHEVs pollute more

Transport & Environment tested three plug-in hybrids and said results show that plug-in hybrids are fake electric cars, built for lab tests and tax breaks, not real driving. OEMs and industry insiders dispute the claims, pointing to the unrealistic test regime.

Transport & Environment (T&E) asked Emissions Analytics to test three of the most popular plug-in hybrids sold in 2019: the BMW X5, Volvo XC60 and the Mitsubishi Outlander PHEV. The study found the plug-in hybrid models emitted between 28 and 89% more CO2 than advertised. With an empty battery, they emitted three to eight times more than official values. In battery-charging mode, allowing drivers to charge their EV battery ahead of a low-emission zone, emissions were three to twelve times higher.

As a result, T&E urges governments to stop all subsidies and tax benefits for plug-in hybrids, even going so far as to call this another emissions scandal.

OEM response

However, T&E has received criticism for its tests, with some pointing out T&E tested routes of 90 to 100km long whereas 90% of all daily trips do not exceed 50km, often spread over several shorter trips, giving drivers ample opportunity to top up their battery.

A BMW spokesperson said: “Plug-in hybrid technology is important to get customers used to electric driving and demonstrate how practical electrified driving is in every-day life. For millions of drivers, today’s PHEV technology already offers the opportunity to cover substantial parts of the daily commute, if not all of it,  using only electric power, whilst having the flexibility of the combustion engine available for longer drives when required. With technology evolving and expanding charging infrastructure, the customer benefits of PHEV technology will continue to grow.”

Mitsubishi also criticised the research, saying: “Our published MPG and CO2 figures are the numbers that are produced as a result of a standardised WLTP test that was specifically designed for PHEVs. Independent tests can produce unreliable / variable figures depending on conditions and a variety of other factors and we naturally contest any findings where we have no oversight of the testing or methodology. Disregarding a PHEV’s electrical powertrain during testing, for example, is like testing a petrol or diesel car and only using three of its gears.”

A spokesperson for Volvo said: “The existing emissions testing regime provides a useful industry standard that allows customers to make comparisons between cars, but real-world variations will apply. Plug-in hybrids have zero, or close to zero, tailpipe emissions when driven in pure electric mode and our customer field data shows that Volvo PHEVs are driven in pure electric mode on average 40% of the time, making them a crucial step in our path to full electrification.”

Earlier studies have also shown environmental benefits of plug-in hybrids rely heavily upon driver behaviour. PHEVs are not intended for drivers that regularly need to cover long distances. For drivers with the right profile, however, they can be a valid option on the path to full electrification.

Find out how you can make fleet electrification work in the next session of the International Fleet Managers Institute (IFMI) on 3 December 2020. Register now!

Image copyright: Shutterstock

Authored by: Benjamin Uyttebroeck