A thesis submitted in partial fulfillment of the requirements for thedegree of Master of Science inRegional and Rural Development Planning

Thesis (M. Sc.) - Asian Institute of Technology, 2012

This research assessessocial, economic and environmentalbenefits of a biogas digester of rural households in the northeast Thailand. The main objective of this study were to examine the extent and purposes on the use of biogas digester of rural households, to assess economic benefits on the use of biogas digester at household and farm levels, to evaluate social and environmental benefits on the use of biogas digesterandto assess satisfaction and needs related to biogas digester and to give recommendations to intensify future use of biogas digester in rural households.The biogas users in this research included 54 rural households divided into two groups namely current and former biogas users which were supported by the Net Foundation in the RLPG project. Out of total sampled households, 32 were those who have ever used biogas digester but were not using at the time of the study, while 22 households used biogas digester at the time when this research was conducted. The data was collected from14 villages in Ta-onk sub-district, Maeung district of Surin Province. A standardized questionnaire was employed to collect data as a prime tool and was supplemented by interviews and a group discussion. The research was mainly focused on a quantitative analysis but with support of qualitative analysis. Main finding of this research showed the main purposesof using biogas digester werecooking and application of its by-product as fertilizer. Main motivational factors to install biogas digesteridentified were saving time and cost of energy. Moreover, the subsidy on construction of biogas from RLPG was also animportant factor affecting the decision on the use of biogas. The economic benefits of using of biogas digester were seen in the decreasein householdexpenditures onLPG, reduction in farm expenditures, and creation of employment opportunity. Decreased deforestation, improved soil quality and better sanitary and hygiene conditions for not only the plant owner families but also for the entire village community were the main environmental benefitsobtainedfrom biogas technology. Furthermore, eye infections and lungs problems, attributable to smell and smoke from the burning of dried cow dung and firewood were also mitigated by the use of biogas digester.The perception on satisfaction of biogas benefits exhibited a high level from both current and former biogas users. Except for the satisfaction on enhanced occupational opportunity, the satisfaction level was assessed highly for all social, economic and environmental benefits of biogas users in both groups. In the using of biogas digester, the most severe problems of biogas users faced are related to lack of technical know-how of the functional and maintenance of biogas digester. Lack of comprehensive training on technical aspects of biogas, lack of budget to cover operational cost, lack of technical skills on the part of project staff and use of sub-standard material were the other major problems identified.A set of recommendations are suggested related to provision technical knowledge, support and skill training, financial support on maintenance system of biogas digester, capacity building of EWG, institutional support from local government, enhancing follow-up, monitoring and evaluation of biogas digesterand a process on screening project participants for a future project to be implemented.