E5 vs E10 Petrol: How Does Affect My Car?

E10 petrol has recently arrived at UK fuel stations, offering a different blend compared to the traditional E5. Understanding how E10 and E5 petrols affect your car is crucial for optimal performance. Make informed choices based on your vehicle’s compatibility with these petrol variants.

E5 Petrol vs. E10 Petrol

The change from E5 to E10 as the new standard unleaded petrol is a concern. For car owners worried about how it may affect the performance of their diesel vehicles. Choosing between E5 and E10 is crucial to ensure your car runs optimally on the appropriate petrol. While E5 is often viewed as a premium option, understanding . Its implications on your vehicle is essential in making the right decision.

What is E5 petrol?

E5 petrol, also referred to as SP95-E5 or SP98-E5, is a type of petrol that is blended with 5% bioethanol. This fuel is suitable for both unleaded 95 and unleaded 98, making it compatible. With regular gasoline vehicles equipped with petrol engines. To maintain its quality, E5 petrol should be stored in a sealed container and kept . At temperatures around 20 degrees for up to 6 months.

What is ethanol?

Ethanol, a renewable biofuel, is extracted from various sources like wheat, corn, and sugarcane, making it a sustainable energy solution.

What is E10 petrol?

E10 petrol, a blend of up to 10% ethanol, is a premium petrol that emits 5% less CO2 emissions than its counterpart, E5 fuel. Making it a significant step towards improving air quality and reducing greenhouse gasses.

 With the potential to save 700,000 tons of CO2 emissions per year. This environmentally friendly fuel has the chance to bring harmful emissions in the environment down by 5%. Contributing to the goal of reaching zero emissions by 2050. Its composition of ethanol not only enhances air quality but also makes. It a safer alternative, benefitting the 300,000 cars equipped to handle it.

How eco-friendly?

The Department for Transport is taking a significant step towards achieving. Its carbon reduction goals with the introduction of the new E10 petrol in the UK. This eco-friendly fuel, containing up to 10% ethanol, has been in circulation in various European countries since the 1980s, including Germany, Belgium, and Brazil.

 In the 1980s, the government introduced ethanol-based fuel in these nations, and now the UK is joining the league with the aim to reduce emissions from diesel and petrol vehicles engine.

The worry of playing a guinea pig is alleviated as over 350,000 cars on the road already use E10 in other countries, proving its success in reducing carbon footprint. 

With the new E10 petrol, the UK is not only keeping pace with global environmental efforts. But also contributing significantly to the reduction of emissions in line with the government’s carbon reduction goals. This marks a positive move towards a more sustainable and eco-friendly future for the nation’s transportation sector.

Will E10 work in my car?

The answer has now been cleared, putting many a motorist’s mind at ease. In most cases, E10 is designed to work with cars manufactured after 2011, encompassing a substantial 18.7 million vehicles on UK roads, as estimated by the RAC. 

However, around 3% of drivers, equivalent to 600,000 vehicles. May find that E10 won’t be compatible with their cars, particularly those running on standard unleaded. For older cars designed before 2011, there is a risk of engine damage due to ethanol, making it an ideal move for people to swap to super-unleaded.

 While the advanced fuel type may come at an average cost of 12p more per litre, it’s worth noting that using E10 in incompatible vehicles poses a potential risk of damage to fragile plastics, metals, and rubber seals. To navigate this issue, it’s probably worth biting the bullet and switching to super-unleaded. 

For those unconvinced, the government has handily set up a website where drivers can check the compatibility of their vehicles by inputting their manufacturer details, providing a full list of models that are deemed compatible with E10, ensuring a safe and efficient use of the fuel.

Can the new type of petrol damage my old car?

  • E10 fuel: Widely used globally, raising concerns about its impact on vehicle performance.
  • Fuel economy: Negligible difference observed with E10 fuel usage.
  • Ethanol content: E10 contains a double dose of ethanol, posing a risk of corrosion to vital vehicle parts.
  • Hygroscopic nature: Ethanol in E10 is hygroscopic, absorbing moisture from the air and attracting water through condensation.
  • Solvent properties: Ethanol acts as a solvent, potentially causing damage to rubber, plastic, and fiberglass components.
  • Modern cars vs. Classics: Modern cars designed for E10, but classics may suffer from increased ethanol levels.
  • Compatibility: Over 90% of cars since 2011 with petrol engines are smart vehicles and compatible with E10.

Is there any difference in performance of the fuels E5 and E10?

The difference in performance between the fuels E5 and E10 is negligible. Both are types of petrol with varying octane ratings, which measure their ability to resist flammable properties. While E10 contains a higher percentage of ethanol, which can cause corrosion in the fuel system over time, modern E10 compatible cars are designed to protect against such damages. It is suggested by manufacturers to use the appropriate petrol for optimal performance and to avoid difficulties in starting the vehicle. The introduction of this new fuel raises questions about its long-term stability and impact on the overall efficiency of the engine.

Is there a difference in cost for both the petrol?

The cost of petrol varies due to several factors such as government taxes and market conditions. In some countries, the use of E10 petrol is incentivized to promote the local production of ethanol, impacting the overall cost. Understanding the content of these incentives and taxes is crucial for consumers to evaluate the cost difference between different types of petrol.

Can we improve the fuel performance?

Through a series of tests, it was shown that adding a fuel stabilizer to E10 fuel is a good thought. However, the tests didn’t stop E10 fuel from degrading, but E5 fuel with the stabilizer added demonstrated less evaporation and just a hint of corrosion. It is concluded that using a stabilizer in E5 fuel provides a greater lifespan, making it safer for the carburettor and preventing ethanol-induced corrosion. Can we further improve the fuel performance by addressing these challenges?

What can happen if I fill my car with the wrong fuel?

Accidentally filling your car with the wrong fuel can potentially cause severe damage to your vehicle. The Department of Transport has repeatedly stated the importance of being careful about the compatibility of fuels. Differences in ethanol content and availability, along with pricing preferences, can be an issue. Such an error not only impacts your vehicle but also has adverse effects on the environment over time. To avoid this issue, it’s crucial to be much more careful when filling your car and ensure that you use the correct kind of fuel.


E10 petrol, a blend of up to 10% ethanol, has recently arrived at UK fuel stations, challenging the traditional E5. The Department of Transport emphasizes the importance of understanding the compatibility of these fuels, as using the wrong fuel may cause severe damage to your vehicle. 

The introduction of E10 marks a positive move towards a more sustainable and eco-friendly future, contributing to the UK government’s carbon reduction goals. However, it’s crucial for car owners to be informed about the potential impact on older vehicles, as around 3% of cars, equivalent to 600,000 vehicles.

 May find E10 incompatible, posing a risk of damage to vital components. While E10 offers environmental benefits, such as reducing CO2 emissions, it’s essential for drivers to check their vehicle’s compatibility to ensure a safe and efficient use of the fuel.


What happens if I use E5 instead of E10?

In its guidelines, the Department for Transport said: “If your vehicle is compatible with E10 petrol, there’s no reason you can’t mix the 2 grades of petrol (E5 97+ and E10 95+). It’s perfectly safe to mix them in the same tank or fill up with E5 if E10 is not available.

Is E5 better for your engine?

E10 is considered a less stable fuel than E5, which could lead to starting issues in some vehicles. Drivers may also need to get used to greater variations in petrol prices, with E10 being influenced by both the wholesale price of oil and the wholesale cost of food crops.

Is E5 petrol OK for older cars?

What’s the problem with classic cars? Although many cars run on E5 without significant problems, doubling the amount of ethanol in the fuel can cause a variety of issues in olders cars. Ethanol is hygroscopic, which means that it absorbs water from the atmosphere. And that water, in turn, finds its way into your car.

What happens if you put E10 in an unleaded car?

Most petrol vehicles built after 2000 are compatible with E10. If your car is E10 compatible you can replace your unleaded petrol with E10 when you fill up. It’s ok to switch back and forth between E10 and other unleaded fuel types, where your manufacturer has advised these fuels are suitable for your vehicle.