What is E10 petrol and can I put it in my car?

If you drive a petrol car, you may be so used to grabbing the standard unleaded pump that you fill up your car without really thinking about it. But did you know that unleaded fuel was upgraded in 2021? This left a question mark over what vehicles are compatible; we’re here to explain all…

What is E10 fuel? 

Containing up to 10% renewable ethanol (which explains its name) alongside 90% unleaded fuel, E10 fuel is a biofuel designed to reduce the emissions of the cars using it. The cars compatible with it do, thankfully, make up 95% of petrol cars on the roads today. If you drive a petrol car, it’s likely that you can use E10 in it, however, it’s worth double checking below. 

What is renewable ethanol?

Would you believe that it all starts with plants? Ethanol is made using alcohol produced from fermenting certain plants. Plants are well known for their positive effects on air quality, so it makes sense to mix standard unleaded with ethanol to make what is an environmentally unfriendly substance a little greener.

What fuel was used before E10?

The petrol widely available before E10 fuel was E5, so the amount of renewable ethanol has essentially been upped by 5%. It’s been estimated that this subtle switch could save 750,000 tonnes of CO2 emissions per year, or the equivalent output of 350,000 cars. With a climate crisis looming large, every little helps. 

Is my car compatible with E10 fuel? 

Whilst E5 could be used in any petrol car without issue, the case with E10 fuel is not quite the same. It’s true that most petrol cars are compatible, but there are a few exceptions, which initially led to delays rolling it out in European countries. 

These exceptions are best queried directly with the car manufacturer, as many petrol models accept E10 fuel apart from select engine types, which will vary between different brands. 

Another way to put your mind at rest about the car you drive and whether the E10 pump is one you can use, is to pop your registration into the Government’s online checker. You’ll need some of your vehicle details handy, such as make, model and engine size. 

Is E10 fuel good for fuel economy? 

Technically, fuel economy is worse on paper, but only by 1%. Driving habits such as travelling with under-inflated tyres and carrying a lot of cargo around in your car will affect your fuel economy more than using E10 fuel instead of E5 will. 

What happens if you put E10 fuel in an incompatible car by mistake? 

The damage E10 fuel could potentially cause to an incompatible car varies from model to model, and depends on how much of the E10 fuel you’ve actually put in, but it’s unlikely to be the end of the world. It’s rare that an engine that usually uses E5 will refuse to run at all on E10, in which case a full fuel system drain would be needed — what’s more likely is problems getting it started initially. 

When your tank of incorrect fuel has gone down by a third or so, just fill it up again with the correct fuel to dilute the incompatible fuel.