Réalisations

SGTM, in partnership with Alstom, participated in the construction of the Afourer Pumped Storage Power Plant (STEP Afourer) in the province of Azilal—a pioneering hydroelectric pumped-storage facility in Morocco. Commissioned in 2004, STEP Afourer has an installed capacity of 465 MW. It pumps water from the lower reservoir (Ahmed El Hansali Dam) to an upper reservoir during the day, then turbines it at night to generate electricity during peak hours. SGTM carried out the civil engineering works for this complex project, notably excavating two inclined vertical shafts and 3 km of underground galleries to connect the two reservoirs (vertical drop of ~800 m). The company also built the underground powerhouse cavern (~80 m long, 40 m high) housing two reversible Francis units of 232.5 MW each. The works required controlled rock mass blasting techniques and the installation of advanced concrete linings for the penstocks (Ø 3 m). SGTM had to manage significant geotechnical risks (gas emissions, karstic water inflows) during tunneling. Close coordination with Alstom was essential for the installation of the pump-turbines and alternators. Funded by JICA (~€500 million), STEP Afourer has been in operation since 2004, acting as an “energy reservoir” capable of storing the equivalent of four hours of production. It remains a flagship of Morocco’s hydroelectric expertise.