The construction work at the powerhouse can continue with some limitation for construction in the rainy season. The procurement process for electro mechanical equipments in the powerhouse can be implemented in parallel with the civil construction work. To obtain an optimum schedule for this part of work, the transportation of equipments to the site should be inline with the time it needs to start the installation work. From the energy simulation study, to minimize the impact to THXP project from the impounding of Keng Seuaten reservoir, the start of impounding should start within the rainy season of the third year. Due to a small reservoir volume, it is expected that the commissioning test for electro mechanical equipments can start at the month of September to October of the third year.