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

From September 2021 the government is doubling the amount of bioethanol in petrol to help reduce emissions. We explain what this means for motorists...

E10 biofuel main image

New, greener petrol will be on fuel station forecourts up and down the country by September as part of a government initiative to reduce greenhouse gases. The aim is that the introduction of E10 petrol will cut transport carbon dioxide emissions by 750,000 tonnes a year, which is the equivalent of removing 350,000 cars from our roads. 

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. Bioethanol is a mixture of petrol and ethanol made from materials including low-grade grains, sugars and waste wood.

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 more than 634,000 cars on UK roads aren't compatible with E10, and 150,000 of these cars were built from the year 2000 onwards. 

“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. 

E10 biofuels fuel filling station labels

Why is E10 being introduced? 

Under the government’s Renewable Transport Fuel Obligation, 9.75% of all transport fuels must come from renewable sources, such as biofuels, by 2021. 

Fuel companies currently put 7% of biodiesel into diesel and 5% of bioethanol into unleaded petrol. The plan is to increase the amount of bioethanol in petrol to 10%. 

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 Secretary Grant Shapps said: "Although more and more motorists are driving electric vehicles, there are steps we can take to reduce emissions from the millions of vehicles already on our roads – the small switch to E10 petrol will help drivers across the country reduce the environmental impact of every journey, as we build back greener."

Will you still be able to buy E5 unleaded? 

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

However, this is likely to be reviewed at some point in the future 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 or use the Government's online E10 fuel checker tool.  

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