摘要:There are 101 municipal wastewater treatment plants in Thailand supplied with electricity and cannot collect wastewater treatment fees. Alternative sources of energy for municipal wastewater treatment would reduce the electricity costs and future fossil energy uses. The Nonthaburi wastewater treatment plant (WWTP) is located in the Northwest of Bangkok and selected due to its available data. The solar energy source is applied to the Nonthaburi WWTP due to the light intensity and the area to install. By comparing to the wind and the biogas sources, the wind speed and the sludge production are not sufficient, respectively. Besides the estimated installation cost of the solar-cell panels among three companies, the NPV of 25 years and the IRR of three percent rate, the area required for installation is an affecting factor for the plant consideration.