Every Smelting Plant in the world must have its own Power Plant and so must PT INALUM. PT INALUM owns a Hydroelectric Power Plant which is located along Asahan River, the only river flowing Lake Toba water to Malacca Strait.

PT INALUM owns three dams. The first one is Regulating Dam in Siruar, around 14.5 KM from Lake Toba. It is to regulate water to be used at Siguragura Power Station. The second dam is Siguragura Intake Dam at Simorea, 9 KM downstream of Regulating Dam. It is to create necessary head to produce power at Siguragura Power Station. Siguragura Power Station is located 200 m underground. The power station is installed with 4 units of generator with 286 MW of each capacity.

The third dam is Tangga Intake Dam at Tangga, 4 KM downstream Siguragura Power Station. It is to create necessary head to produce power at Tangga Power Station. Tangga Power Station is installed with 4 units of generator with 317 MW of each capacity.