Producing bioethanol

You can make bioethanol fuel from a variety of sugar and starch-rich materials, mainly by fermentation (where bacteria digest the material in a low oxygen environment) and distillation. It can also be produced by the reaction of ethylene with steam.

Food crops such as corn, wheat, sugar cane and sugar beet, barley and rye can be used in the fermentation process, as well as leftovers from food crops after the edible parts have been removed, waste straw, willow, reed canary grass, cord grasses, Jerusalem artichoke, myscanthus and sorghum plants, or most other plants. Domestically grown wheat and sugar beet are the sources mostly used to manufacture bioethanol for transport, in the UK.

When you produce bioethanol by fermentation, there is a residue called distillers' dried grains with solubles (DDGS). DDGS are classified as a by-product and not a waste if they are used without further processing, either as animal feed or as a fuel. Waste management controls will not apply to your DDGS if you meet these requirements - e.g. you do not need to transport it using a waste carrier or with a waste transfer note.

Producing biogas

Biogas can be produced from biodegradable materials including maize crops and wastes, including municipal or food wastes. The biodegradable material is turned into a gas by anaerobic digestion, using bacteria to break down the organic matter without oxygen in specially designed digesters.

You can then refine the biogas, for example using a membrane separation technique, to remove the CO2 and impurities and produce biomethane. You can use biomethane as a vehicle fuel.

Permits, licences and authorisations required

You may need a pollution prevention and control permit or waste management licence if you produce your own bioethanol or biogas. See the page in this guideline: Do you need a permit or licence to produce biofuel?

In Scotland

You should use guidance from the Scottish Environment Protection Agency (SEPA) to help you assess whether your biomethane is a waste or not.

SEPA: Is it waste? (PDF, 52K)

The solid waste from anaerobic digestion is called digestate and it can be used in a similar way to compost, taking care to avoid causing pollution.  

If you produce digestate from biodegradable wastes that meets a certain standard then it will no longer be classed as waste. If you don't achieve this standard then you must follow waste management controls when you handle, transport or apply the digestate. 

In Northern Ireland

The Environment Agency, the Northern Ireland Environment Agency (NIEA) and the Waste and Resources Action Programme have created a quality protocol for anaerobic digestate from biodegradable wastes.

WRAP: The Quality Protocol for anaerobic digestate

If you follow the protocol you can produce a high quality digestate which can be sold without waste management controls. For example, if it is not classed as a waste, you do not need to transport it using a waste carrier or with a waste transfer note.

If you don't achieve the standards in the quality protocol then you must follow waste management controls when you handle, transport or apply the digestate.

Quality standards for biofuels

You must meet specific quality standards to sell your fuel in countries within the European Union. These standards apply to biofuel and blends containing biofuel. See standards for biofuels in the European Union: European Union Biofuel specifications (on

The European Committee for Standardization (CEN) promotes standards for the safety of workers and consumers and to protect the environment, in the European Union: European Committee for Standardization (CEN)

Further information

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