Assessment of small hydropower in Songkhla Lake Basin, Thailand using GIS-MCDM

Due to environmental issues associated with large dams, small hydropower (SHP) has recently won social acceptance in Thailand as a clean and predictable energy resource. This study was aimed at identifying small run-of-river hydropower sites in Songkhla lake basin (SLB) Thailand. An integrated geographical information system (GIS), soil and water assessment tool (SWAT), and analytical hierarchy process (AHP) approaches were adopted to identify potential sites based on technical, economic, and environmental criteria. Many potential SHP sites were first mapped using ArcGIS and their water discharges were modeled using SWAT. The weights of economic and environmental criteria were calculated using AHP. Nineteen SHP sites in the Songkhla lake basin were finally chosen and ranked based on their economic and environmental scores, with total power generating capacities of 2.3 MW, 2 MW, and 1.5 MW at 50%, 75%, and 90% flow dependencies. The sites identified in this study can be developed to provide clean, reliable, and cost-effective electricity to their surrounding communities. The development will help improve the local socio-economic outlook while reducing power imported from adjacent areas. The method adopted in this study can be applied in any other river basins around the world for sustainable hydropower potential assessment.