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

A new blend of petrol with double the amount of bioethanol has been introduced to help reduce emissions. We explain what it means for motorists...

E10 biofuel main image

New, greener petrol is now on fuel station forecourts up and down the country as part of a government initiative to reduce greenhouse gases. The hope 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 was previously the norm 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 delayed was the concern that it can cause damage to older cars. 

E10 biofuels fuel filling station labels

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.

Its director Steve Gooding said: "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. 

Why has E10 been introduced? 

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

The introduction of E10 was 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 cars, 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."

    Can you still buy E5 unleaded? 

    Although E10 unleaded petrol is now sold at all filling stations, high-volume outlets that sell more than three million litres of fuel a year are also allowed to stock ‘protection grade’ E5 for the time being, so that owners of older cars will be able to fill up with this. 

    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.  

    It's also worth noting that E5 petrol has been renamed super-unleaded and that it is likely to cost 10-12p per litre more than E10. Although car owners using E5 will get marginally better fuel economy than those using E10, the additional cost of buying it could put a strain on drivers who are on a tight budget. 

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