Performance assessment for small-scale biogas plants in Sub-Saharan Africa

Abstract

Biogas production issues are generally connected with poor maintenance of the plant, characterised by the unavailability of a daily and regular feeding activity, inadequate cleaning and stirring system, and inefficient use of biogas. In addition, the overlooking of socio-cultural values can contribute to the expansion of performance issues since it affects directly the work approach and behaviour of biogas owners. In a technical point of view, gas leakage is the most common issue occurred, and the plant design is a crucial aspect that influences the future performance of the biogas system. The main operational issues that negatively affect the biogas performance are the blockage of the inlet pipes, insufficient feeding activity, and the corrosion of biogas appliances. The amount of feedstock and water added in the plant is the most important information that necessitates a daily control but also other important parameters such as temperature, gas production, pH value, and agitation system. In terms of socio-cultural factors, it was possible to notice a common hierarchical attitude towards their workers among the biogas owners interviewed. This aspect was supported by a lack of communication between workers and owners hindering the interest of the first to share opinions and to take initiatives. The general context is characterised by the presence of vertical networks where limited cooperation among members of different groups dominates. As a result, the lack of technical support after the installation of the system from the biogas providers to biogas users hinder adequate maintenance. since the owners usually don't have sufficient technical knowledge to evaluate any problems.