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Fuel knowledge

Petrol, diesel and alternative fuels explained

Fuel labels can describe the blend, the performance specification or what the fuel is designed to power. Here's what the common terms mean and what to check before choosing one.

PETROL

E5, E10 and octane ratings

E5 and E10 describe the maximum ethanol content in petrol. The 95 or 98 octane number describes resistance to engine knocking. They refer to different fuel properties, so don't treat them as interchangeable labels.

  • •E5: up to 5% ethanol
  • •E10: up to 10% ethanol
  • •Use the minimum octane grade specified by your vehicle maker
DIESEL

Standard and premium diesel

Premium diesel products may use different additive packages and product formulations. The exact specification varies by brand; a premium label does not guarantee a measurable benefit for every vehicle.

  • •Use the diesel grade specified in your handbook
  • •Compare product claims rather than assuming all premium fuels are the same
  • •Never use a fuel simply because it is marketed as higher quality
EXHAUST FLUID

What is AdBlue?

AdBlue is a separate fluid used by many diesel vehicles with selective catalytic reduction systems to reduce nitrogen oxide emissions. It is not a fuel and must never go into the diesel tank.

  • •Use the dedicated AdBlue filler
  • •Follow the vehicle manufacturer's instructions
  • •Do not dilute or substitute other fluids
HOME HEATING

Kerosene and home heating oil

Home heating oil is commonly used in domestic oil-fired boilers. It is supplied for heating equipment, not as a substitute for road diesel or petrol. Always use the fuel specified for your appliance.

  • •Check the boiler and burner requirements
  • •Order the correct heating-oil grade
  • •Keep storage and delivery equipment maintained

Beyond petrol and diesel

What about alternative fuels?

The wider fuel landscape also includes biofuel blends, LPG and other gaseous fuels, electricity and hydrogen. Availability, vehicle compatibility and refuelling infrastructure vary, so the right option depends on the vehicle and how it is used.

BiofuelsLPGCNGElectricityHydrogen

Want the wider Fuel 101 guide?

Pick A Pump's guide covers traditional and alternative fuels, including E10 petrol, premium diesel and home heating oil, with context for cars, farms and homes.

Read Fuel 101 on Pick A Pump

Which fuel should I use?

Use the fuel type and minimum specification stated by the vehicle or appliance manufacturer. For E10 compatibility, check the handbook, fuel flap label or official compatibility information for your exact model. If you are unsure, ask the manufacturer or a qualified garage rather than relying on the vehicle's age alone.