E10 biofuel - what is it and how could it affect you?

The government wants to double the amount of bioethanol in petrol to help reduce emissions. But this could render many older cars undrivable. We explain why...

E10 biofuel main image

New, greener petrol could be on fuel station forecourts up and down the country by 2021 as part of a government initiative to reduce greenhouse gases. However, not all petrol cars will be compatible with the new fuel, which is called E10.

What is E10 fuel?

It’s petrol that contains twice as much bioethanol as the E5 unleaded that’s currently sold in the UK: 10%, as the name suggests. This type of petrol is sold elsewhere in Europe, including France and Germany, and all new cars sold in Europe since 2011 are able to run on it. 

However, even though fuel suppliers have legally been able to sell it in the UK since 2013, one reason they have chosen not to is the concern that it will cause damage to older cars. 

What’s the problem with E10? 

The RAC Foundation estimates that there were 868,517 petrol cars on British roads last year that were incompatible with the new fuel. By the time it is introduced in 2020, this number will still be more than 634,000, with 150,000 of these cars built from the year 2000 onwards. 

“As and when E10 appears on the forecourts, drivers need to know whether their cars can use it without being damaged,” said Steve Gooding, director of the RAC Foundation. 

“While some of those vehicles incompatible with E10 fuel will be historic models, many will be old but serviceable everyday runabouts that people on a tight travel budget rely on to get about.” 

The problem appears to be significant. It is believed that the higher bioethanol content in E10 petrol could dislodge deposits in older engines and fuel systems, causing blockages; it could also cause some seals, gaskets, metals and plastics to corrode. 

The RAC Foundation’s research shows that vehicles that should be judged incompatible with E10 fuel travelled a total of 2,534,757,877 miles in 2017 – so we’re not talking purely about little-used classics, but a fairly big chunk of our national car stock. 

E10 biofuels fuel filling station labels

Why is the introduction of E10 being considered in such a time frame? 

Under the government’s Renewable Transport Fuel Obligation, 9.75% of all transport fuels must come from renewable sources, such as biofuels, by 2020. 

Fuel companies currently put 7% of biodiesel into diesel and 5% of bioethanol into unleaded petrol. The proposal is that petrol should contain 10% of bioethanol by 2020. 

To find out if, and how, E10 fuel should be introduced in the UK, the government launched an eight-week consultation in July. It was also considering whether the grade of unleaded petrol with 5% bioethanol should remain on sale at a reasonable price and whether it should introduce new fuel labelling at petrol pumps and on new cars. 

The aim of E10’s introduction is to help the government meet its climate change targets. Bioethanol absorbs carbon dioxide, and it is estimated that every vehicle that switches to E10 will produce 2% less greenhouse gases. 

Transport minister Jesse Norman said: “The government is ambitiously seeking to reduce the UK’s reliance on imported fossil fuels and cut carbon emissions from transport. But drivers of older vehicles should not be hit hard in the pocket as a result. 

“We have launched this consultation in order to understand the impact of E10 on the UK market better, and to ensure that drivers are protected if any changes come into effect.”

It's also worth noting that there are experts who appear to disagree with the RAC Foundation's findings. In 2012 Germany’s ADAC organisation carried out a search for examples of E10 compatibility incidents in that country and found none.

Will you still be able to buy E5 unleaded? 

Although the proposals state that E10 should replace E5 unleaded petrol at all filling stations, high-volume outlets that sell more than three million litres of fuel a year would also stock ‘protection grade’ E5 for older cars to use. 

But this is likely to be reviewed after 2020 and then E5 unleaded could disappear from forecourts. If you own an older petrol car and are concerned that it might not be compatible with E10, we’d recommend that you contact the manufacturer for confirmation on this.  

Skoda Fabia Estate (00 - 07)

Cars that won’t run on E10 biofuel 

Using DVLA data, the RAC Foundation says post-2000 cars still on the road that won’t run on E10 include some petrol versions of these models: 

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