ballestic PETROL vs DIESEL
What Car? UK|March 2023
Diesel has long been the fuel of choice for high-mileage drivers, but with it now costing an average of 22p more per litre than petrol, is it still the better option?
George Hill George
ballestic PETROL vs DIESEL

THERE ARE MANY factors that can impact your decision when choosing which fuel to power your car, but one key element is running costs.

Traditionally, for those who rack up a lot of miles and make mostly motorway journeys, diesel cars have been the default choice for the additional fuel economy they offer over petrol equivalents. However, after the recent inflation in fuel prices, the cost of diesel has risen significantly above that of petrol; at the time of writing, the RAC states that diesel is 22p more expensive on average per litre.

So, with that in mind, does it still make sense for high-mileage drivers to head to the black pump, or does the green nozzle make more financial sense?

THE EXPERIMENT

To compare the two fuels, we gathered six cars: three petrol-powered models and their diesel twins. We then tested them back to back on a mixed route of town, A-road and motorway driving to collect real-world economy figures.

The cars we chose included two family hatchbacks, two estate cars and two large SUVS. More specifically, we picked a Peugeot 308 1.2 Puretech, a Peugeot 308 1.5 BlueHDi, a BMW 320i Touring, a BMW 320d Touring, a Genesis GV70 2.5T and a Genesis GV70 2.2D. Why the variety? Well, as part of our investigation, we wanted to see how the fuel cost difference impacts different types of car, which vary in engine size, power output and weight.

Our test route started at a petrol station in Virginia Water, Surrey, where we brimmed the tanks and made our way down to Junction 9 of the M3 towards Winchester. Once we arrived at Junction 9, we swapped drivers and the positions of the cars and followed the same route back to the Virginia Water petrol station, where we refilled the tanks and crunched the numbers. The round trip totalled 84 miles.

ENSURING A FAIR TEST

Denne historien er fra March 2023-utgaven av What Car? UK.

Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.

Denne historien er fra March 2023-utgaven av What Car? UK.

Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.

FLERE HISTORIER FRA WHAT CAR? UKSe alt
Genesis GV60
What Car? UK

Genesis GV60

Does this plush newcomer deserve a slice of the premium electric SUV pie? The verdict is in

time-read
3 mins  |
November 2024
BYD Dolphin
What Car? UK

BYD Dolphin

Smallest BYD gets a smaller battery and a slimmer price tag to make it more competitive On sale Now Price from £26,195

time-read
2 mins  |
November 2024
BMW i5
What Car? UK

BMW i5

Our electric executive saloon disproves the notion that battery-powered cars aren't as efficient out of town

time-read
2 mins  |
November 2024
Kia EV6
What Car? UK

Kia EV6

Electric SUV gets a larger battery, revised suspension and a new infotainment system On sale October Price from £45,575

time-read
3 mins  |
November 2024
Maserati GranTurismo Folgore
What Car? UK

Maserati GranTurismo Folgore

Range-topping electric version of Maserati's four-seat coupé packs a 751bhp punch, along with an official range of 280 miles On sale Now Price from £179,950

time-read
2 mins  |
November 2024
Mercedes-Benz C-Class
What Car? UK

Mercedes-Benz C-Class

Looking for all the world like a shrunken S-Class limo, the latest C-Class executive saloon is a tempting used buy with a major trick up its sleeve

time-read
3 mins  |
November 2024
Cupra Terramar
What Car? UK

Cupra Terramar

Bigger sister to the Formentor completes Cupra's combustionengined SUV line-up On sale Early 2025 Price from £35,000 (est)

time-read
2 mins  |
November 2024
Skoda Kamiq
What Car? UK

Skoda Kamiq

We're finding out whether this updated small SUV makes a good workhorse for a high-mileage driver

time-read
3 mins  |
November 2024
Honda e:Ny1
What Car? UK

Honda e:Ny1

Should you consider this small electric SUV over a Smart or Volvo EX30? We're living with one to find out

time-read
3 mins  |
November 2024
PLUGS RETHINK
What Car? UK

PLUGS RETHINK

It may look radically different from before, but is the latest Toyota Prius a cut above its refreshed plug-in hybrid rival from Volkswagen?

time-read
8 mins  |
November 2024