The new fuel has replaced the previous E5 as the standard 95 RON unleaded at forecourts across the country as part of efforts to cut the UK’s CO2 emissions.
While most modern cars can safely run on E10 petrol, it is thought that as many as 600,000 cars, half of which are in daily use, are incompatible with the new fuel and could suffer damage if filled with it regularly.
To address this, any filling station that previously sold two grades of unleaded will continue to offer the old E5 but only as the more expensive 98 RON super or premuim unleaded.
Is my car E10 compatible?
If your vehicle was built after 2010 it is compatible with E10 petrol.
Most cars built between 2000 and 2010 are also compatible but there are some exceptions, including models from major brands such as Audi, Ford, Mercedes, Toyota and Volkswagen.
Older cars, including classic models are more vulnerable to damage from the fuel.
The Government has created an E10 compatibility checker for drivers to look up their specific car and check its suitability. You can access the service via the Government website.
What if my car is not E10 compatible?
For the hundreds of thousands of cars that can’t run on E10 fuel, drivers will still be able to access E5 unleaded at some filling stations.
At filling stations which currently sell two grades of unleaded, E10 will become the regular unleaded, while E5 will be sold as premium or super unleaded. This will increase the cost of filling up for drivers of older cars.
In remote rural areas covered by Rural Fuel Duty Relief Scheme, such as the Scottish Islands, filling stations will not be required by law to sell E10.
The DfT has said it will protect the supply of E5 fuel for at least five years.
What happens if I use E10 petrol in an incompatible car?
Misfuelling with E10 petrol will not cause immediate damage to your car but prolonged use could lead to long-term problems.
E10 contains more ethanol than E5 petrol, which poses two main risks to incompatible cars. The first is that as a solvent, it can cause degradation of rubber and plastic components, such as hoses, seals, fuel lines and filters. It also absorbs water from the atmosphere, potentially leading to condensation and corrosion in fuel tanks, lines and other metal components.
Classic car insurance brand Hagerty has warned that the change could cause significant damage to the fuel system and engine of older cars, with the RAC advising that the fuel isn’t suitable for any car built before 2002.
The European Automobile Manufacturers' Association has also advised that if you misfuel a car with E10 you should contact your dealer, the vehicle manufacturer or roadside assistance provider who may advise that the fuel tank be drained.