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Regular, premium or ethanol | which petrol is best for me?

E10, regular or premium petrol? Which is best for your car?

The range of fuels available at the pump can be confusing, especially from a price perspective.

While the price pain of visiting the bowser has eased in recent months, many drivers are still unsure about whether it pays to fill up using premium petrol or a cheaper variation.

Some will spend around 12 cents extra per litre for premium fuels, but is it worth it?

A spokesperson from Australian Automobile Association's says there's no clear-cut answer to whether it does give you better value for the distance travelled.

"There is evidence to show you might get more from a tank of premium, but you need to do your research to see if you're saving any money," they say.

"You might go further in distance but the fuel itself will cost more, which means you may not be always be in front."


"My advice is do a test tank with one fuel and then with the other," the spokesperson says.

Australia's current fuel standard is 91 Research Octane Number, which most vehicles accept, but a growing number need 95 RON premium fuel, and some even require 98 RON. The octane rating is a standard measure of fuel performance.

Experts say the golden rule is to always use the fuel that is recommended by the manufacturer - many European cars require the car to only run on premium unleaded.


NRMA vehicle safety expert Jack Haley says there's a simple way to work out whether premium is worth it.

"The maximum improvement by using a higher octane fuel is about 1 per cent per octane number, so if you go from 91 to 95, the maximum reduction in fuel consumption is about 4 per cent," they say.

"If the price difference between 91 and 95 is less than 4 per cent and your vehicle does experience improvement...then it is worth switching to premium.

"But given 95 fuel is about 12 cents more a litre than 91, which is usually a lot more than 4 per cent, then there's no advantage in using premium fuel."


A spokesperson from RACQ says driving conditions can significantly affect petrol consumption, and while premium fuel goes further, it does cost more and may not always leave you better off.

"We looked at a comparison of E10 fuels to premium unleaded and we compared that across two Holden Commodores over about eight days," they say.

"We found there was a fuel consumption penalty by using E10 of around 2 to 3 per cent, which correlates with the expected fuel consumption increase.

"Basically, E10 fuels will see a person experience higher fuel consumption when they are using an ethanol-based fuel."

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