Analysis of the Causes of Digester Malfunction in the Biogas Project in Beyla Prefecture, Republic of Guinea

Abstract

This study analysed the functionality of biogas digesters installed through the biogas project in Beyla Prefecture. The methodology involved a survey of biodigester owners. Data collected using KoboCollect were processed with QGIS 3.24 and SPSS 21. The project facilitated the construction of 177 biogas digesters in Beyla Prefecture, which constituted the study population. A sample of 133 biogas digesters, representing 75% of this population, was selected for the survey. Of the 133 biogas digesters surveyed, 8 (6.02%) were owned by women and 125 (93.98%) were owned by men. During the project phase, 130 biodigesters were operational (97.74%). After the project ended, only 10 remained operational (7.52%), 116 were non-operational (87.22%), and 7 operated seasonally. The main reported reason for abandoning biodigesters was the long distance travelled to collect cow dung, which accounted for 62 biodigesters, or 50.41% of the responses. This was followed by odours during the mixing of organic waste (14.63%) and breakdowns (12.20%). Of the 133 biodigesters surveyed, 100 produced biogas used exclusively for cooking, representing 75.19% of respondents, while 22 owners (16.54%) used both biogas and charcoal. After the project, 88 of the 133 biodigester owners (66.17%) used firewood for their primary energy needs, while 31 (23.31%) used charcoal. Only 7.52% used both biogas and charcoal, and 3.01% used butane. Of the 88 owners who used only firewood, 64 reported that women and girls collected the wood, representing 72.73%. Biodigester use may therefore reduce the household burden associated with firewood collection, which was reported to fall mainly on women and girls.