Prius Fuel

I am from the US and we do not use RON but AKI but I will try. (I am also very ignorant of your money)

E10 petrol will have 3% less energy and should get 3% less miles per gallon. If the difference between BP and 7Eleven is under 3% (or the change in mileage you notice) then BP is actually cheaper. It will be more likely that you save more with the E10 even with the reduced mileage. as the 15c per gallon may be more than 3%

So try the 7Eleven petrol but track MPG with both, and then do some math.

(if you use l per 100km instead of MPG, you are still looking at a 3% difference, in theory)

 

You'd have to ask our EU experts, but we all use E10 here in USA and it works fine in Prius. E0 is hard to find here and very expensive in general.

Normally here we recommend the cheapest option which is E10 91 RON Octane Regular.

But the USA gasoline pool is designed for good quality of the lower octane as the most common fuel (about 90% of the market). Our EPA basically took away any games the oil companies used to play. The oil companies used to use better detergents and energy in the higher octane. Now they cannot do that, and even the oil companies do not recommend Premium here if you do not need it.

In your case, the Premium might have some advantages such as better detergents and maybe more energy (MPG). You should try the cheaper 98 Premium as far as I know there is not issue with it. If E10 is cheaper that might make sense, maybe use Premium once in a while for the added detergents if any.

 

You're in the States, England, Germany??