What is E10 petrol and should you use it?

Passenger cars, classic cars and motorcycles will all need further protection as the ethanol content in fuel rises. Below our technical advisor explains how this will affect our vehicles and what you can do to combat this.

What is E10 fuel?

E10 unleaded petrol could be in the fuel pumps from 2021, in short the amount of ethanol in our current fuel will double from 5% to 10%. The 90% part is regular unleaded petrol and the ethanol part of the fuel is a government drive to increase the biofuel produced in terms of renewable energy from crops to reduce or at any rate try to reduce emissions.

What it does

Ethanol increases the octane rating of petrol, this is key for resisting detonation so that the fuel has a control burn rather than an explosion or pinking*. So in effect the role of ethanol is beneficial to the efficient running and power delivery of a petrol engine.

Why is it bad?

Ethanol itself is very corrosive and ethanol with moisture (that it holds) is also very corrosive to steel fuel tanks, glass fibre and certain rubber hoses and fittings. Ethanol has a lower calorific energy content that petrol, this can impact on the fuel economy of a vehicle with the consumption increasing.

How can we combat its effects?

Millers Oils has developed fuel treatments to deal with the proposed E10 fuel. VSPe Power Plus tackles classic vehicles right to the birth of the automobile whilst EPS is for the more modern cars and motorcycles. It works by inhibiting this corrosive behaviour by joining with any free bonds on the ethanol. This effectively stops the corrosion from even starting. The fuel treatments will not affect the beneficial part of ethanol i.e. make combustion more efficient.

*Pinking – also known as ‘pre-ignition’ is caused when the temperature and compression combination within the cylinder gets high enough to cause ignition of the fuel/air mixture without the use of a spark plug.