Plug-in hybrid vehicles (PHEVs) are touted as a transition drivetrain that can help drivers take that first step towards a zero emissions transport future. But according to Greenpeace, they are “the car industry’s wolf in sheep’s clothing”.
PHEVs typically have smaller batteries than all-electric vehicles with an all-electric driving range of just 50-80 kilometres, although they can also drive longer distances using a combination of electric power and fuel, and are preferable to hybrid-only vehicles such as the Prius because they can be plugged in at the wall.
Car makers sell PHEVs on a promise that they have far lower emissions than their petrol and diesel equivalents, as well has non-pluggable hybrid vehicles.
But a new report that studied plug-in hybrid vehicles in Europe by transport lobby group Transport & Environment (T&E) suggests that actual usage patterns – and manufacturer’s operating parameters – paint a very different picture.
The report, which was undertaken in collaboration with environmental lobby group Greenpeace, shows that emissions from PHEVs are on average 2.5 times higher than those shown in official tests.
“The CO2 emissions from a typical PHEV are about 117g CO2/km4 on the road only slightly better than from a conventional hybrid car like a Toyota Prius 135g CO2/km.5 A conventional new ICE car has emissions of 164-167g CO2/km on the road6 (diesel and petrol respectively),” the reports authors write.
“Over the lifetime of the vehicle a new PHEV in 2020 will emits about 28 tonnes of CO2, slightly less than a conventional hybrid car (33 tonnes).7 In comparison a conventional petrol or diesel car emits 39 and 41 tonnes respectively.
“A new battery electric car will emit about 3.8 tonnes from the electricity it uses over its lifetime. (Assumptions are detailed in the annex.) It is clear PHEV emissions are much more comparable to those of conventional cars than electric cars,” they write.
According to the report, the top ten PHEVs sold in the UK claim to have an “EV only” mode but the reality is that it is the manner in which the vehicle is driven, the ambient temperature and the use of heating or cooling that makes it very difficult to achieve any 100% pure electric driving.
Greenpeace UK’s head of politics, Rebecca Newsom described PHEVs as “the car industry’s wolf in sheep’s clothing”.
“They may seem a much more environmentally friendly choice but false claims of lower emissions are a ploy by car manufacturers to go on producing SUVs and petrol and diesel engines,” she says.
The UK is planning to ban the sale of petrol and diesel vehicles from 2035, and is considering bringing it forward five years to 2030.
However according to UK’s Auto Express, the National Franchised Dealers Association has urged the Government to “reconsider the benefits of plug-in hybrid vehicles” and exclude them from the ban. Norway, on the other hand, is going ahead with a ban on plug in hybrids from 2025 in its pursuit of 100 per cent battery electric vehicles.
“It’s great that the government is considering bringing the ban on new petrol and diesel vehicles forward to 2030, doing so is one of the most important things the government can do now to help tackle the climate emergency,” says Newsom.
“But ministers mustn’t be duped by plug-in hybrids when making this critical decision – it’s imperative that they are included in the 2030 ban, and that support is provided to enable workers to transition to electric vehicle manufacturing.”
Amongst the criticism levelled at car makers by the T&E report are the fact that the Kia Niro PHEV, when in EV-only mode, fires up the engine on if the demister is turned on.
One driver told T&E that their Niro PHEV still used its engine even when in Eco+ zero emissions mode – and when the vehicle was checked by a Kia engineer they were told it was operating correctly.
Kia also told T&E that, “When the coolant temperature is lower than 14 °C, and you turn the climate control on for heating, the vehicle will automatically switch to HEV mode as the engine is required to provide heat for the passengers.”
T&E also reports that similar issues apply to Volvo’s XC90 SUV plug-in hybrid, and Mercedes-Benz E Class PHEVs, which turn on the engine if it is too cold outside.
It also labels Mitsubishi’s Outlander PHEV as misleading, saying its even when its “EV” button is on, it will still turn the engine on if adaptive cruise control is being used or if it is too hot or too cold outside.
Jaguar Land Rover’s range of PHEVs also have problems, it says. Both the Range Rover and Range Rover Sport PHEVs fire up the engine when extra power is needed, generally because the electric motor cannot generate enough power on its own under demanding conditions. The same is true for the Porsche Cayenne PHEV, says T&E.
When driving over a certain speed, T&E also points out that BMW PHEVs and the Mini Countryman PHEV will also fire up the engine.
Greg Archer, UK director of Transport & Environment said in a statement that, “PHEVs are not electric cars and claims that in cities plug-in hybrids have zero emissions are just mischievous, misleading marketing.”
He points out that if PHEVs are to be able to claim low emissions status, they must be charged regularly.
“Unless the battery is frequently charged, these fake electric cars are actually worse for the climate than conventional cars,” he says.
Bridie Schmidt is lead reporter for The Driven, sister site of Renew Economy. She specialises in writing about new technology and has been writing about electric vehicles for two years. She has a keen interest in the role that zero emissions transport has to play in sustainability and is co-organiser of the Northern Rivers Electric Vehicle Forum.