by Felix Reeves
are worse than
for some harmful
new research has
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
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
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
James Hobday, Business Development Director at Emissions
Analytics commented on the findings.
"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."
worse for the environment than diesel cars.
"The VOCs we found,
like benzene and formaldehyde, are in notable quantities. We
still require research into what quantities of VOCs are
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
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
Before 2035 we will
continue to regulate emissions from non-electric vehicles."