Soubré hydroelectric power scheme inaugurated in Ivory Coast

The inauguration ceremony

On the 2^nd of November 2017, the President of Ivory Coast Mr Alassane Dramane Ouattara attended the official inauguration ceremony for the Soubré hydroelectric power scheme. He was joined by the Prime Minister and more than 10 Ivorian ministers including the supervising Minister for Oil, Energy and Renewables, alongside representatives of CI-Energie (the client). The foundation stone was also laid at the downstream development of Gribo Popoli HPP.

The Ambassador of China, representatives of Sinohydro and Eximbank, Mali’s Minister of Energy and Hydraulics, as well as several representatives from Tractebel were invited to take part in the event. Tractebel was mentioned many times in the various speeches and the medal of Knight of the National Order of Merit was awarded to Jean Teyssieux, Director of Hydraulics, by the supervising Minister in thanks for services provided within the framework of this project. Jean-Michel Bocquet, Chief Engineer, and Brice Tchuinkam’su, Chief Resident Engineer of the Soubré Dam, also represented Tractebel at this event.

Tractebel’s mission

Tractebel’s mission on this project spans nearly 20 years. From 2000, Tractebel, under the banner of Coyne et Bellier, updated the Soubré development study based on different retainer options and in 2008, after having updated the feasibility studies, then the tender documents for a BOOT development, Tractebel signed the contract for supervision of construction works on October 2012. Around fifteen engineers at head office as well as residents on the worksite were allocated the various service roles including the following missions:

• Assistance in compiling the carbon credit file
• Environmental impact study
• Lines of transport study
• Control of studies and technical assistance
• Supervision of Works and acceptance of works
• Follow-up during the period of notification of the defects
• Transfer of competence – training

It is worth noting that the Soubré hydro power scheme was certified in January 2017 under the United Nations Clean Development Mechanism (UN-CDM) with sale of carbon credits. It is a first in this domain. One of the missions of Tractebel, in collaboration with AERA Group, was to support the client CI-Energies in its mission to have the project accredited and to pursue, by their side, the steps linked to reducing CO2 emissions.

The hydro development

The Soubré site is located on the Sassandra River around 120 km from the sea, at the Nawa Falls. The construction works, which lasted 4 years, allowed a dam to be built – a barrage 19 m high and 4.5 km long leading in the south to a 275 MW power plant (three Francis groups of 90 MW each), which enables an annual generating capacity of more than 1,200 GWh. The development also includes a spillway (5,500 m³/s), a mini-hydropower plant (5 MW) driving turbines with the instream flow (50 m³/s), a water intake linked to three penstocks of 8 metres in diameter, an outlet canal of 2.5 km, a motorway bridge, the switchyard and 380 km of 225 HT power line linking the cities of Soubré and Abidjan.

This development, completed a year ahead of schedule, is today the biggest of its kind in Côte d’Ivoire. It allows the country to increase its electric power by 10%, a momentum that will continue with the construction soon of an additional plant, to be further enabled by two other planned plants. Ivory Coast currently has an electrification level of 50% and aims to move from a capacity of 2,000 MW to 4,000 MW by 2020.

The Soubré hydro development is part of the strategy of Ivorian authorities to promote an energy mix with an increase in the hydro share (which should shift from 30% to 45% by 2020) associated with other renewable energy sources (mainly solar) for a share estimated at 5%. This energy mix is aimed at reducing the share of thermal energy by 50% and to lighten the gas bill while highlighting the strong commitment by Côte d’Ivoire to combat global warming.

All works were achieved by the Chinese company Sinohydro which is also poised to commence construction of the next Gribo Popoli HPP. Soubré project cost: €500 million with 85% financed by EXIMBANK, 15% funding by the Ivorian State.