by Felix Reeves
November 22, 2021

from Express Website



SOME hybrid vehicles

are worse than diesel cars

for some harmful emissions,

new research has revealed...

Channel 4's Dispatches program has discovered that certain groups of potentially harmful pollutants are worse in some new hybrid cars than some new diesels.


Hybrids are the most popular form of electric vehicle in the UK, accounting for nearly a quarter of all new car registrations in September 2021.

Mild hybrids (MHEV) which use diesel have seen a 79.6 percent increase in registrations since 2020, while petrol MHEVs saw a 184.1 percent jump.

Despite their growing popularity, new research has shown hybrids not to be as environmentally friendly as they appear.

Hybrids contain both an electric motor and a fuel tank, which makes the vehicle heavier and less efficient in terms of needing to fill up more often.

With an electric motor, hybrids can reduce exhaust emissions of carbon dioxide, nitrogen oxide and particulate matter.

However, volatile organic compounds - VOCs - are chemicals that are emitted as gases from some liquids including petrol and diesel.

At certain levels some VOCs can cause cancer or cause ground-level smog.

Dispatches worked with Emissions Analytics, a group of exhaust experts, to test emissions from nine cars: six hybrids which all use petrol, two diesels and one pure petrol car.

All the cars were put on the open road for testing and the results showed that, in a cold start, all hybrids performed worse than the new diesel car, emitting higher levels of VOCs.

Many VOC gases that are emitted from exhausts, including formaldehyde, are not currently measured or regulated by the Government.

The Government is still pushing ahead with its plan to ban the sale of new petrol and diesel cars in 2030, with a similar ban coming in 2035.

James Hobday, Business Development Director at Emissions Analytics commented on the findings.

He said:

"It's often a simplification when people look at emissions to say that electric is good and diesel is bad. In cold starts, VOCs for the electrified cars were often much higher than for diesels."

"And the diesels were even cleaner than the petrols. The prevailing wisdom that electric cars are clean when it comes to VOCs it isn't the case."

Some hybrids

are worse for the environment than diesel cars.

(Image: Getty)

"The VOCs we found, like benzene and formaldehyde, are in notable quantities. We still require research into what quantities of VOCs are acceptable"

In response to the findings, the Department of Transport told Dispatches:

"We're on course to become the first G7 nation to fully decarbonize cars and vans.


Hybrid cars and vans have an important role to play to achieve our phase-out date and will only be allowed to be sold between 2030 and 2035 if they deliver significant zero emission capability."

"By 2035 all new cars and vans will be zero emission at the tailpipe.


Before 2035 we will continue to regulate emissions from non-electric vehicles."