Draft PPS18: Renewable Energy
C28. Anaerobic digesters installed at municipal sewage works typically range in volume from 180m3 to 3,400m3. The tank can be as high as 15 metres, although it can sometimes be partly buried. In addition to reducing the visual impact, partial burial offers heat insulation benefits and so reduces the energy demand of the digestion process.
Annex 1 Energy from Waste (Biological Processes) Technology: Sewage Gas