E10 petrol: Drivers warned they may have to use 'premium' fuel instead

Over the summer, the standard unleaded petrol supplied through the pumps will change from E5 fuel to a new formula called E10, designed to reduce emissions.

But the new fuel, which will not affect diesel owners, will not be compatible with all cars and vehicles as the Government has warned.

In those situations, some cars over the age of ten will need to use the more costly 'super' grade, also known as premium fuel, instead.

What is changing and why new fuel is coming in

Currently, unleaded and premium petrol supplied to UK pumps contains 5 percent of renewable ethanol and is known as E5.

But during summer 2021, a newer fuel with ten percent of renewable ethanol will be introduced at petrol stations known as E10.

The Government says the change is designed to help reduce the overall levels of CO2-based vehicle emissions.

It says that the difference in a year could be the equivalent of taking 250,000 cars off the road, or all of the cars in North Yorkshire, as a result. 

What cars and vehicles are affected

As a result of the reduction in ethanol, the formula is not compatible with some cars and continued use of unleaded could cause damage to the vehicle.

According to the Department of Transport, cars using the new fuel when it is not compatible could suffer from major mechanical issues.

Footman James says this could be anything from blocked fuel filters, damaged fuel pumps, degradation to flexible fuel hoses to corroded carburettors.

The Government has said all petrol pumps will be clearly marked during the rollout, meaning drivers will know whether or not they can use unleaded for the time being.

It has since created a 'vehicle checker,' which can be accessed here, which allows drivers to check whether their cars, motorcycles and mopeds can use E10.

It has said the following may not be compatible:

- classic, cherished and older vehicles

- some specific models, particularly those from the early 2000s

- some mopeds, particularly those with an engine size of 50cc or under

It said: "All new cars manufactured since 2011 are compatible with E10 petrol, and most cars and motorcycles manufactured since the late 1990s are also approved by manufacturers to use E10."

How much it will now cost

It is no secret that premium fuel costs more than unleaded, sometimes costing more than 15 pence extra per litre.

According to the RAC's fuel watch, the average price of unleaded as of July 14 stood at 133.6p per litre, whereas premium cost drivers 142.6p per litre.

It means a £30 tank of petrol could soon set you back around £2.70 more when filling up with premium.

But mistakes will be forgiven

The Government says you should be able to fill up with premium petrol next time, and that you should avoid repeating this mistake.

It means drivers don't need to worry if they accidentally use E10 in the same way as they would if fuelling a diesel car with petrol, and vice versa.

It said: "Using a single tank of E10 petrol in a vehicle that is not compatible should not be a major problem. 

"Unlike putting petrol into a diesel engine, you shouldn’t need to drain the tank. On a one-time basis, your vehicle will not suffer engine damage as a result.

"Prolonged use of E10 petrol in a non-compatible vehicle, however, may cause harm and is not recommended."

What the industry has said

Earlier this year, and as E10 plans were cemented, the industry reacted with some offering assurances that the majority of petrol car owners will not be affected.

Simon Williams, RAC fuel spokesman, said: “The switch to E10 petrol is clearly good news for the environment and will not affect the vast majority of the UK’s 33m car drivers although some may see the number of miles they get from a tank go down as research suggests E10 is potentially slightly less efficient.

“It’s estimated that around 700,000 cars registered prior to 2002 shouldn’t use E10 as seals, plastics and metals may be damaged by its corrosive properties if used exclusively over longer periods.

"It’s vital that anyone with an older vehicle gets the message about the switch otherwise they could end up with a big repair bill.

"Those with no option but to continue using E5 will have to fork out quite a lot of extra money as super grade unleaded is currently 136p a litre which is over 13p more expensive than regular petrol.

"There’s also a danger that E5 premium grade petrol may be harder to find in some more rural locations.

“And while there will be no visible impact on prices at pumps, the reality is that the higher cost of bioethanol has already been included in the wholesale cost some time ago.

"In fact, in the last 12 months the price of a litre has gone up by more than a penny simply because of the biocontent being stepped up gradually to 10 percent.”