US $567.7m Isimba Hydropower Dam in Kayunga District Uganda has been officially commissioned by President Museveni. “The construction and completion of Isimba dam gives confidence to investors that Uganda has adequate and reliable electricity,” said President Museveni.
Isimba Hydropower Dam
The 183.2MW (245,700 hp) power plant is located at the village of Isimba on the Victoria Nile, in Kamuli District, approximately 44 kilometers, by road, north of the Bujagali Hydroelectric Power Station.
Construction of the project which was built by China International Water & Electric Corporation (CWE) with Artelia and KKATT being the project consultants began in 2015. It features a five-floor office complex which has control unit to regulate functioning of turbine generators, transformers and swtichyard.
The project extends over approximately 2,867.6 acres of land and it comprises of a concrete gravity dam, a clay-core rock fill dam, a spillway, a power house, electro-mechanical equipment, switching stations, and auxiliary power transmission works.
The concrete gravity dam consist of a reservoir retaining structure in front of the erection bay. The rock fill type with central clay core right dam is to provide storage for emergency gates and stop logs.
The powerhouse structure features four 45.8MW Kaplan turbines. The Isimba HPP external switchyard is connected with the powerhouse by four overhead lines.The 183MW electricity power at Isimba dam will be transmitted over 42kms to Bujagali dam switchyard to load on national grid.
The electricity generated, is set to increase power on the national grid to slightly over 1,000MW. This could prompt tariff reduction for large-scale consumers supplied from the national grid. Energy Minister Permanent Secretary Mr Robert Kasande, however noted that the power price reduction is not immediate for everybody across the board at once.
Technical staff at Isimba have been running tests of gradual loading of the electricity generated from the dam onto the national grid since last December, when the plant was originally planned to be commissioned.
Reduced electricity cost
The potential energy in the water from the reservoir converts to kinetic energy as it plunges, in the case of Isimba dam, 25 metres to spin the turbine blades inside the power house.
The rotation of the blades, generate mechanical energy that powers on the generators. Copper wires in the generators cut the magnetic fields, inducing electricity in the copper wires. This electricity is conducted to the transformers on the back of the power house.
Uganda Electricity Generation Company Ltd (UECGL) said it will sell the electricity it generates at about US $5 cents per unit or 1,000 watts, lower than the US $8 cents charged for Bujagali dam power.