Geothermal energy is one type of renewable energy which the Thailand government sets a geothermal policy to increase the power generation to be 1 MW in 2021. Department of Mineral Resources of Thailand [1] reports 112 hot springs in Thailand. In 2008, Chiang Mai University (CMU) [2] also reported 97 potential of hot springs in Thailand and classified them into three groups as high, moderate and low potential which is shown in Figure 1. For high potential hot spring, the surface water temperature is higher than 80°C. Moderate potential hot spring refers the surface water temperature between 60-80°C and low potential hot springs represents the surface water temperature is lower than 60°C. Thus, the aim of this research is to study the appropriate technologies for using geothermal energy in Thailand.