IT´S A common question that often triggers big arguments. Is branded petrol and diesel better than supermarket fuel, or should you just buy the cheapest you can find?
The problem is that most people don’t know how the fuel business works, and the truth is a well-kept trade secret.
Premium fuels, such as Shell V-Power Nitro+ and BP Ultimate, are not the same as regular petrol or diesel , although you can mix them freely with standard fuels without problems.
Petrol like this is known as ‘super unleaded’. Confusingly, the petrol that is labelled as ‘premium unleaded’ on forecourt pumps is actually standard petrol. When it comes to fuel, super is better than premium!
These ‘super unleaded’ fuels cost several pence per litre more than regular unleaded. For this extra money, you get a different, more sophisticated package of additives for cleaning and lubrication, and fuel with a higher octane rating.
It’s a similar story with ‘super’ diesels, like BP Ultimate Diesel.
Octane (petrol) and cetane (diesel) ratings describe the way a fuel burns inside an engine. Broadly speaking, a higher rating means a fuel will burn more efficiently and effectively inside your engine. This may improve performance and/or economy slightly – although not all drivers will see a noticeable difference.
All fuels sold in the UK conform to the relevant British Standards. This means that they should all work in roughly the same way and you can mix them freely in your car’s fuel tank.
The standard petrol and diesel that’s sold on garage forecourts is mixture of two things – Base fuel and an additives package.
The base fuel is the same for all companies – in fact, it usually comes from the same tanks at the local fuel refinery/distribution centre. What varies is the additives package that goes into the fuel. These additives packages are secret recipes of extra ingredients that help keep the engine clean and improve lubrication inside the engine cylinders.
Each fuel company has its own additives packages and these are different. So it is possible (but not common) for some drivers to feel that their car responds better to the additives used by one fuel manufacturer over those of another.