With the gap between the cost of diesel and unleaded continuing to widen - in some parts of the UK this chasm is as high as 30p! – many motorists will be questioning why diesel is so much more expensive than petrol.

Diesel car drivers are paying far more to fill up their vehicles than petrol car owners, and there are many reasons why this is the case. Read on to discover more…

Diesel has to be imported

Whilst 58% of the cars on our roads are petrol and less (36.9% to be exact) are diesel according to the latest research, domestic, UK-based refineries have always struggled to meet demand when it comes to supplying diesel fuel. This has meant that the cost of diesel has always been historically higher than petrol.

The increasing gap between diesel and petrol prices however is a cause for concern. With diesel traditionally imported from Russia, the situation has intensified as supplies are now imported from alternative countries due to the conflict between Russia and Ukraine.

Supplies are lower for diesel

More recently, OPEC+ - The Organisation of the Petroleum Exporting Countries – announced that it was cutting oil production by two million barrels per day. The lower rate of production has seen a sharp spike in the price of wholesale refined fuel. A fact that has only widened the price gap between petrol and diesel even more.

Diesel contains additives

Unbeknown to most, diesel contains a number of additives that effectively push its price up. Whilst similar to the additives found in petrol, the lower volatility of diesel makes their addition more complicated, time consuming and costly.

Diesel is more economical

One of the perks of owning a diesel car instead of a petrol alternative is its fuel economy. With fuel efficiency higher than their petrol counterparts, diesel cars are better for longer journeys or motorists that incur higher mileage.

Diesel fuel contains far more energy per litre than petrol, giving their owners a better MPG. This may explain the historically higher fuel cost as well as the higher diesel vehicle sale and resale values found industry-wide.

Fuel duty takes its toll

Whilst petrol and diesel are both taxed the same here in the UK, it is important to note that British motorists pay some of the highest tax rates in the world on their fuel.