Fuel for Thought: Everything you need to know about E10 petrol

Ellie Dyer-Brown, 2 years ago

5 min read

  • Advice
  • buyingguide
Petrol Pumps

In a bid to reduce CO2 emissions by as much as 750,000 tonnes per year, a new, greener grade of petrol known as E10 has been introduced across the UK.

The old grade of petrol (95 octane), known as E5, contained only 5 per cent renewable ethanol, while the new grade contains up to 10 per cent. 

The move to E10 is part of the U.K. Government’s Renewable Transport Fuel Obligation (RTFO), through which over 12 per cent of road transport energy will come by 2032. 

The UK isn’t alone in its adoption of E10 petrol. Many countries, including those throughout the EU, already use it. 

Guide Contents:

How the switch affects UK drivers

What if my car is incompatible with E10 fuel?

The benefits

The downsides

When will E10 be introduced?

How the switch to E10 fuel affects U.K. drivers

The vast majority of drivers will be unaffected by this change since 95 per cent of all petrol cars on the road today are able to use E10 fuel. 

However, some vehicles that were manufactured before 2011 may not be compatible with the new fuel grade. It has been estimated that around 600,000 vehicles on our roads will fall into this category. Those most at risk include:

  • Some models from the early 2000s.

  • Mopeds with an engine size of 50cc or less.

  • Classic cars

If you're not sure whether your vehicle is compatible, use this free online checker.

What if my car is incompatible with E10 fuel?

If your current vehicle is not compatible with E10 petrol, it doesn’t mean you need to purchase a new one in order to continue driving. Many larger filling stations will offer ‘super’ grade fuel (97+ octane) which will be more suitable for your car. 

Unfortunately, using super unleaded E5 petrol comes at a premium, with prices averaging around 147p per litre (or around 12p more expensive than the current average price of E10 unleaded petrol). 

If you accidentally fill your vehicle up with the wrong grade of fuel, there’s no need to panic. Unlike filling a petrol car up with diesel, you won’t need to drain the tank; your engine will not be damaged. You should avoid doing this frequently, however, as long term use of the incorrect fuel grade could harm your car’s engine. 

The benefits of E10 fuel

As previously mentioned, it has been estimated that using greener fuel like E10 will reduce emissions by as much as 750,000 tonnes per year. This is equivalent to taking 350,000 cars off the road. Why? Because E10 contains a higher percentage of ethanol which can be produced via biological processes from plants, making it more environmentally friendly.

The downsides to E10 fuel

The irony in the move from E5 to E10 is that the Government’s own Impact Assessment report states ‘there are no clear consumer advantages to choosing E10 fuel’ and that the 2032 target could be achieved without the introduction of E10. For the estimated 600,000 drivers who will be forced to pay more for ‘super’ E5 petrol, this news, coming at a time when fuel prices are already at an eight-year high, definitely won’t be welcome.

Moreover, ethanol is about a third less dense than pure petrol, so switching to E10 fuel will likely impact your car’s fuel economy. What Car? magazine conducted research on four E10 compatible vehicles using both E5 and E10 petrol, with the latter suffering a reduction in fuel economy ranging from 6 to 11.5 per cent when using E10. 

When will E10 fuel be introduced in the U.K.?

The wholesale roll out of E10 petrol takes place in September 2021. In addition to its introduction of E10 fuel, the UK Government is also planning to ban the sale of all new petrol and diesel cars by 2030 in a bid to cut carbon emissions 78% by 2035. 

In response, it’s clear that electric and hybrid vehicles are going to become ever more commonplace on our roads the closer we get to this date. Whether or not this change is welcomed by U.K. drivers is less certain. A recent WhoCanFixMyCar study found that 64.5% of people would still choose a petrol car over electric or hybrid, even if they were all the same price.


E10 petrol explained - GOV.UK (www.gov.uk)

Is E10, the new 'green petrol', suitable for your car? (telegraph.co.uk)