What are biofuels?

Transport biofuels are a renewable alternative to the use of the limited resources of fossil fuels. They can be liquid or gas, and can help to reduce your business transport emissions. The impact that biofuels have on reducing CO2 emissions will depend on where they come from and how they are produced, and how they are used.

The two types of biofuel most used in the UK are biodiesel and bioethanol. Biogas, another type of biofuel, is currently limited within the UK.

What is biodiesel?

Biodiesel is a substitute fuel produced for diesel engines. It is a renewable fuel made from vegetable oil crops, for example rapeseed or soybean. You can also make biodiesel from waste cooking oils. It doesn't contain petroleum and is biodegradable.

Biodiesel can be mixed with normal diesel to make a blended biodiesel. This is available in a variety of blends including:

  • B5 - Has up to 5 per cent biodiesel in ultra-low sulphur diesel - most commonly available
  • B30 - Has up to 30 per cent biodiesel blend in ultra-low sulphur diesel - only available from a limited number of outlets
  • Has up to 100 per cent or pure biodiesel (B100) - available from specialist suppliers.

Most of the diesel you buy at petrol stations already has some biodiesel added to it. You can use the 5 per cent blend with no engine modification and it will not affect your vehicle warranty. You should contact your vehicle manufacturer before using a higher blend, as it could affect engine performance and warranty if your engine is not modified.

In Northern Ireland, standard pump diesel now contains 10 per cent biodiesel. 

What is bioethanol?

Bioethanol is a renewable fuel used as a petrol substitute, for petrol vehicles. It is made from starches or sugar, for example corn or sugar cane. It is biodegradable and less toxic and explosive than petrol.

You can use bioethanol in different blends to fuel vehicles:

  • E5  - Has up to 5 per cent bioethanol, in unleaded petrol
  • E10 - Has up to 10 per cent bioethanol, in unleaded petrol.

Most of the petrol you buy at petrol stations already has some bioethanol added to it. In most cases you won't need to modify your engine to use a 5 or 10 per cent blend of bioethanol. 

Most petrol vehicles manufactured after 2011 are able to run on E10. Older petrol vehicles may usually only use E5. You can check if your vehicle can run on E10 on the GOV.UK website: GOV.UK: Check if your petrol vehicle can run on E10

Both in Northern Ireland and Scotland, standard pump petrol now contains 10 per cent bioethanol (E10). E5 is now only available as "Premium blend".

What is biogas?

Biogas is a renewable fuel made from biodegradable materials including maize crops and wastes, such as municipal or food wastes. The main component of biogas is methane. Biogas can be purified to produce liquid biomethane (LBM), which can be used as a vehicle fuel. You can also purify landfill gas to produce biomethane.

Using biomethane in road vehicles can greatly reduce CO2 emissions compared to those from diesel use. It also reduces emissions of nitrous oxides and has no particulate (dust) emissions.

Biomethane can be stored as a compressed gas for road vehicles. Any vehicle that can operate on compressed natural gas (CNG) or liquefied natural gas (LNG) can run on LBM.

Some commercial vehicles operate on biomethane - for example heavy goods vehicles, vans and buses. However, a number of new models operating on biomethane are due to come onto the market in the next few years, and the use of biogas should continue to increase.

Biobutanol and biopropane are also used as renewable transport fuels.

Examples of innovative biofuel production and use include:

Other alternative fuels

For details about other alternative transport fuels, see the page on how to use alternatively powered vehicles in our guideline Reducing your vehicle emissions

Further information

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