The Karuma hydropower project is a 600MW run-of-the-river power plant under construction on the Nile River, in Kyandongo District, Uganda.
Estimated to cost $1.7bn, the hydroelectric project is being jointly developed by Uganda’s Ministry of Energy and Mineral Development (MEMD) and Uganda Electricity Generation Company Limited (UEGCL), with the help of Chinese funding.
The project broke ground in August 2013 and is scheduled to commence operation in July 2019.
Karuma will be the biggest power generation facility in Uganda, upon completion, while the Karuma dam will be the largest dam in East Africa.
Karuma hydroelectric plant will represent a significant addition to Uganda’s national grid, as the country’s total electricity generation capacity currently stands at 950MW.
Karuma hydropower project location
The project is located at Karuma Falls, approximately 110km downstream of Lake Kyoga, along the Kampala-Gulu highway, 270km from Uganda’s capital Kampala.
Karuma hydropower project development history
Karuma was originally planned to be developed as a 200MW hydroelectric plant by Norpak, a Norwegian energy company, which acquired exclusive rights to develop the project in 1996.
Norpak, however, pulled out of the project in 2008, alleging lack of support from the World Bank and the Ugandan Government.
The Ugandan government subsequently decided to develop the project with a higher capacity of 600MW, after feasibility studies in 2010 confirmed the adequacy of water flow at Karuma Falls to generate potentially more electricity.
The 600MW project took off in 2013, with Sinohydro roping in as the engineering, procurement and construction (EPC) contractor.
The parliament of Uganda approved the government’s request to borrow foreign funds for the construction of the Karuma hydropower plant, in March 2015.
Karuma hydropower project financing
The $1.7bn project is financed 85% through a soft loan from the Export Import (Exim) Bank of China, while the Ugandan government provides the remaining 15%.
The loan amount will be repaid over a period of 25 years, at an average interest rate of 3%.
Karuma hydropower plant make-up
Karuma hydroelectric power station consists of a 20m-high and 312m-long roller compacted concrete (RCC) gravity dam, six 20m-high and 29m-wide water intake towers, six 7.7m diameter and up to 379m-long concrete lined pressure shafts, and a 200m-long, 21.3m-wide and 53m-high underground power house cavern housing six 100MW vertical Francis turbines.
The reservoir for the hydropower plant is 35km-long and occupies an area of 2,737ha. The gross reservoir volume is estimated to be 79.87 million m³.
The design discharge for the hydropower plant will be 1,128m³/s and the turbines of the plant will operate under a gross head of 70m, at a speed of 150 rotations per minute (rpm).
The power generated from the plant will be evacuated from the underground transformer cavern located just above the underground powerhouse. The 200m-long, 18.0m-wide and 14.4m-high transformer cavern will house six 11kV/400kV step-up transformers and will be connected with the powerhouse through 40m-long bus duct tunnel.
The power station is also built with two 314m-long, 21.5m-wide and 50m-high restricted orifice type tailrace surge chambers, from where water will be sent back to the river through two 12.9m diameter horse shoe-shaped tailrace tunnels of approximately 8.6km length.
Electricity transmission from Karuma hydropower plant
The electricity generated by the plant will be fed into the national grid through three transmission lines, which include the 248km-long 400kV Karuma-Kawanda line, the 55km-long Karuma-Olwiyo line, and the 80km-long Karuma-Lira transmission line.
The project also involves the construction of three new substations at Karuma, Kawanda and Olwiyo, by Uganda Electricity Transmission Company (UETCL).
Contractors involved with Karuma hydropower project
Sinohydro was awarded the engineering, procurement and construction (EPC) contract worth $1.65bn, for the Karuma hydropower project, in September 2013.
Alstom (now GE) was awarded a contract worth $65m by Sinohydro in October 2015, to supply six 100MW Francis turbine-generator sets and related equipment for the Karuma hydropower facility.
Shandong Taikai Transformer, a wholly-owned subsidiary of China’s Taikai Group, was contracted to supply the transformers for the power plant.
AF-Consult Switzerland was appointed as the project management consultant for the Karuma hydropower project in January 2016.
Energy Infratech, an engineering consulting company based in India, was selected as the owner’s engineer for the project.
Energy Infratech had also carried out the feasibility study for the 600MW Karuma hydropower project.