This hydroelectric project, under a BOT scheme promoted by the Instituto Costarricense de Electricidad (ICE), benefits from exhausted waters from ICE’s Cachí plant. The water is taken by a connecting structure from Cachí’s exhaust outlet to a tank featuring a discharge and restitution channel system. The tank is connected to an 8km long low-pressure tunnel, discharging into an hourly regulation reservoir with a dissipation structure for exit and intake at antechamber as the beginning of the penstock. The powerhouse has 3 vertical shaft Francis turbines for an installed capacity of 50 MW under a net head of 104 m. 5.60 m wide tunnel dug with tunnel boring machine and prefabricated segmental lining.
CARBON Engineering, in consortium with RSW International, was hired by Ghella Spa, EPC contractor of the project, to conduct a value engineering study, develop the final design and construction plans. The contract was executed together with RSW Inc. of Canada.