China Eximbank pledges $4.923 billion loan for 3,050MW Mambilla Hydroelectric Power Plant Project (Linked to Record ID#1844)

Project narrative

On September 14, 2017, the Government of Nigeria approved the 3,050MW Mambilla Hydroelectric Power Plant Project. The total cost of this project is $5.792 billion and it will reportedly be financed according to an 85:15 debt-to-equity ratio. China Eximbank has agreed in principle to provide a $4.923 billion buyer’s credit and the Government of Nigeria has agreed in principle to provide an $868.8 million equity contribution. The project would involve the construction of four dams, two underground powerhouses having 12 turbine generator units in total, and a 700-kilometer transmission line. The four dams to be constructed on the Dongo River for the Mambilla hydropower project include Nya (formerly known as Gembu), Sumsum, Nghu and Api Weir dams. Nya and Sumsum will be 100m and 35m-tall roller compacted concrete (RCC) dams with crest length of 515m and 460m, respectively. Nghu will be a 95m-high rockfill dam with a crest length of 650m, while Api Weir will be a small regulatory dam to raise the water level of the river. Nya and Sumsum dams will be connected through a 16km-long, 6m-diameter tunnel, whereas Sumsum and Nghu dams will be connected by a 1.5km-long and 10m-wide canal. The headrace canal for the plant will be 3.1km-long and 15m-wide. Each underground power house of the plant will measure 175mx27mx38m and house six 250MW Pellton turbine units operating at a total dynamic head of 1,007m.The diameter of the power shafts connecting each turbine will range between 5.25m and 8.40m. Two 6km-long tailrace tunnels for the plant will be of 8m diameter each, while the tailrace canal will be 3km-long and 25m-wide. Upon completion, it is envisaged that the electricity generated by the power plant will be sold to the Transmission Company of Nigeria, which will in turn transmit it to two locations, where it will be integrated into the Nigerian electricity grid: a 330kV high voltage transmission line will connect to Jalingo and four 500kV high voltage transmission lines will connect to Makurdi. This high voltage transmission system will measure 700 kilometers in length. Construction is expected to take at least seven years from start to finish, due to the technical complexity of the project. However, some sources suggest that a more realistic completion date is in 2030. The project is expected to generate 50,000 temporary and permanent jobs. On August 30, 2017, Nigeria’s Federal Executive Council (FEC) approved the award of the construction contract for this project to a consortium (joint venture) that consists of Gezhouba Group, Sinohydro and CGCOC Group. In November 2017, there were attempts to start construction of the hydroelectric power plant. However, due to various constraints, including landslides, and a lawsuit at the International Court of Arbitration, the project stalled. Then, following the resolution of the lawsuit, the Government of Nigeria formally applied for a loan from China Eximbank on August 26, 2019.