Anaerobic Digestion

Anaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. It is used for industrial or domestic purposes to manage waste and/or to release energy.

AD is used as part of the process to treat biodegradable waste and sewage sludge.  As part of an integrated waste management system, anaerobic digestion reduces the emission of landfill gas into the atmosphere. Anaerobic digesters can also be fed with purpose-grown energy crops, such as maize.

WREN is assessing the scale of available feedstock, and working with commercial partners to provide AD to process locally collected food-waste to generate heat and power.  We are also looking at a related process, which can loosely be termed Thermophilic Digestion, with the aim of converting food waste to a direct fuel for a biomass boiler. Biomethane injection is subject to an RHI payment of 6.5p/kWh, and electricity generated from AD attracts the following FIT rates:

WREN is undertaking a feasibility study to find out whether we as a town could create heat and power (eg for one of the schools or the Sports Centre) from the food we currently throw away.  If you could help out with this by simply weighing the amount of food you throw away each week please pop in to the Energy Shop, or email  This email address is being protected from spambots. You need JavaScript enabled to view it.
Or, simply download this form, follow the instructions on it, and email it back to the above email address.

Click here to download more information about AD