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 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, were hired by Ghella Spa, EPC contractor of the project, to conduct a value engineering study, develop final design and construction plans. The contract was executed together with RSW Inc. of Canada.