Regarding the construction, operation and maintenance of household biogas plants, the construction of fixed dome digesters is labour intensive and requires skilled supervision [21]. Construction materials are not always available in rural and remote communities, but they are generally available in larger nearby communities. Plastic tubular digesters are characterised by the ease of implementation and handling. Most importantly, they do not require specialised manpower. On the other hand, high quality prefabricated plastic bags might not be locally available and require importation. Nevertheless, all construction materials can be easily transported