Environmental guidance for your business in Northern Ireland & Scotland

Anaerobic Digestion

Anaerobic digestion plant and tractorAnaerobic Digestion

You may be able to treat your biodegradable waste using anaerobic digestion. This uses natural bacteria to convert waste into:

  • biogas, which can be used to generate electricity and/or heat
  • liquid, which can be used as a fertiliser
  • solid, which can be used a soil improver.

Increasingly AD is being used to make the most of our waste by turning it into renewable energy.

What you must do

Operating an anaerobic digester

Before you operate an anaerobic digester to treat food waste you must have a pollution prevention and control (PPC) permit, waste management licence or registered exemption.

Pollution prevention and control permits

Waste management licences

You may need to register a paragraph 13 exemption for composting and storing biodegradable waste in Northern Ireland. If you have an exemption, you must comply with the exemption conditions.

DAERA: Paragraph 13 Composting and storage of biodegradable waste

If your waste includes animal by-products you must have approval for your anaerobic digester from Animal Health in Scotland or the Divisional Veterinary Offices (DVO) in Northern Ireland.

Animal by-products and food waste

Burning biogas as fuel

If you burn biogas you must have a:

  • waste management licence for appliances with a rated thermal input up to 3 megawatts
  • a pollution prevention and control permit for appliances with a rated thermal input of 3 megawatts or more.

Pollution prevention and control permits

Waste management licences

You may be able to register an exemption from the need to hold a permit or licence if your appliance has a net rated thermal input of less than 0.4 megawatts.

If you operate under a registered exemption you must still ensure that your activity does not:

  • endanger human health
  • cause pollution to water, air or soil
  • cause a risk to plants or animals
  • cause a nuisance in terms of noise or odour
  • adversely affect the countryside or places of special interest.

DAERA: Paragraph 7 – burning of waste as a fuel in an appliance

SEPA: Waste management licensing exemptions

DAERA: Waste management licensing simple exemptions

DAERA: Waste management licensing complex exemptions

SEPA has produced guidance that explains how they will regulate the use and handling of digestate outputs from the AD process.

SEPA: Regulation of Outputs from Anaerobic Digestion Processes

Further information on the production of biogas and case studies can be found on the Anaerobic Digestion Portal.


Whats new on NetRegs

  • Waste – Duty of Care Roles and Responsibilities

    The Northern Ireland Environment Agency has published a short guide to the duty of care responsibilities including advice and information for waste producers, carriers and those accepting, storing and treating waste.



  • EIA (Agriculture) Regulations for Northern Ireland

    Any person intending to alter the use or management of areas of uncultivated or semi-natural land must obtain prior approval from the Department of Agriculture, Environment and Rural Affairs (DAERA).

    Read more on the DAERA website

  • Guidance from your environmental regulator

    Regulator logos

  • 9 NEW GPPs (Guidance for Pollution Prevention) available now

    The NetRegs team at SEPA, in partnership with The Northern Ireland Environment Agency, Natural Resources Wales and a number of industry bodies have produced 9 new GPPs to replace out of date PPGs. More are coming! Check the available topics

  • New guidance

    New guidance for Start-ups, charities and community projects


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