Integration of multicriteria decision analysis and geographic information system for site suitability assessment of Napier grass-based biogas power plant in southern Thailand

Napier grass is a promising energy crop owing to its advantages over other energy crops; however, when determining sites for the power plants utilizing Napier grass as a feedstock, relevant data are required. The spatial distribution of the Napier grass dry matter yield (DMY) is among these important data. Unlike agricultural residues, the spatial distribution of the DMY cannot be obtained through surveys or statistical data. In this study, a methodology for locating biogas power plants utilizing Napier grass as a feedstock is proposed. A geographic information system and analytic hierarchy process are used to evaluate land suitability for biogas power plants based on environmental and socioeconomic criteria. The spatial distribution of the DMY is integrated with the land suitability map to locate suitable sites for biogas power plants. The proposed approach is applied to southern Thailand because the region lacks self-sufficient power generation. The results reveal that, five biogas power plants that utilize Napier grass from abandoned areas can be established with a total contracted capacity of 420 MW. Based on this analysis, introducing Napier grass-based biogas power plants could significantly help reduce the dependency on imported electricity. Stakeholders are recommended to treat this study as a tool to be utilized before implementing new dedicated energy crops.