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What are biofuels?

Biofuels are fuels for transport made from plant or animal materials. Two common biofuels are:

• biodiesel: made from vegetable oil crops like palm or soya, and waste vegetable oil. It can be mixed with standard diesel and used in normal diesel engines
• bioethanol: made by fermenting starchy and sugary crops such as sugar beet and wheat. It is mixed with petrol

Biofuels have the potential to reduce the climate change impact of transport because the plants they are made from take in carbon dioxide (CO2) when they grow, helping balance out the CO2 that is given off when they are burned. They can also help improve energy security because they reduce our dependence on oil and gas.

A 5 per cent blend of biodiesel is already widely used throughout Europe and, since April 2008, in much of the UK. This is suitable for use in all diesel vehicles without any modification, and it is dispensed through normal pumps. A 5 per cent blend of ethanol is also sold in some filling stations.

There are also a small number of UK filling stations supplying higher blends of biofuel which are only suitable for use in special vehicles.

• Where can I fill my car up with greener fuels? Opens new window
• More about renewable energy
• Learn more about CO2 and climate change

Some biofuels are better than others

The best biofuels can help tackle climate change. However, some biofuels provide no climate change benefit, can lead to loss of important habitats and wildlife, and can have negative social impacts such as rising food prices. 

Some potential problems include:

• growing biofuel crops requires fertilizers, which take a lot of energy to produce, and can lead to pollution and soil erosion. These and other impacts from producing and transporting biofuels can reduce, or even cancel out, the benefits of the resulting biofuel
• increased production of biofuels will need more land to grow the crops they are made from. This could be taken from land currently used for growing food, or created from natural habitats like forests or wetlands, which can have serious consequences for the environment. For example forests and peat wetlands play an important role in storing large amounts of CO2, as well as being important wildlife habitats. If forests are cut down or wetlands drained for biofuel crops then the negative impacts from the CO2 released can outweigh savings made by the biofuel
• some biofuels are made from crops that are also used for food. Increased demand for biofuels could force up the price of these crops, making food more expensive

Many governments around the world are trying to encourage increased biofuel production and this increase is happening rapidly. The scale and speed of these changes mean that the balance between benefits and potential negative effects from biofuels are still not fully understood. 

The Renewable Transport Fuel Obligation (RTFO) and action to encourage the best biofuels

The Renewable Transport Fuel Obligation requires UK fuel suppliers to include a certain amount of biofuel in the fuel that they supply. In order to encourage them to source the best biofuels, fuel suppliers are obliged to report on:

• the amount of greenhouse gases (including CO2) that have been saved by supplying the biofuel, compared to the fossil fuel that it has replaced
• the way in which the biofuel is produced, to help ensure that any negative environmental or social impacts are minimised

The government has said that no more than 5 per cent fuel in the UK will be biofuel until it can be sure that it is supplied in a way that avoids negative side effects (like habitat loss or impacts on food prices). They are also campaigning for the EU's proposed target, of 10 per cent of vehicle fuel to be biofuel by 2020, to be conditional on the indirect impacts of biofuels being adequately addressed.

• More about the Renewable Transport Fuels Obligation Opens new window
• The Renewable Fuels Agency Opens new window
• More about how the RTFO encourages the use of the best biofuels Opens new window