Dis-adoption of small-scale biogas plants in Vietnam: what is their fate?

Biogas production at a small-scale level through anaerobic digestion has been promoted in Vietnam as an appropriate technology for cooking and animal waste management within rural households. Despite the large number of small-scale biogas plants being built, there is an increase in the reported cases of their dis-adoption. This study attempts to present the state of the art of biogas plants' abandonment issue and reveal the fate of biogas plants. The primary data were collected in Thua Thien Hue province in central Vietnam among owners of small-scale biogas plants selected with the purposive sampling technique. Methods included semi-structured interviews with respondents who abandoned their biogas technology (at least 6 months before the primary data collection) (n = 37) and with respondents who continually use it (n = 62). SPSS 25 IBM was used for the binary logit model with 6 independent variables. Using a logistic regression analysis of various cross-sectional data, key forces were uncovered to determine the factors that can influence the abandonment of biogas technology. Results showed that households with more members working on the farm and those more satisfied with the biogas plant maintenance are less likely to abandon it. Respondents provided the information that their biogas plants mainly were not used for any other purpose after dis-adoption (excepting biogas plants used for further storage of human excreta because they were connected to toilets).