The client determined that the generating equipment, first installed in 1933 and renewed in 1943, required rehabilitating, due to excessive downtime and increasing component failure. From a lifetime cost analysis, various technical options were identified.
The initial option by the client to only replace the turbine regulator was revised, and the option to replace the complete turbine and generator, adopted. This option minimised the cost of production identified in the extensive financial modelling exercise.
The rehabilitation option identified was executed by Pöyry as the main Engineering, Procurement and Construction (EPC) contractor, managing and assuming all construction and interface risk through to completion and handing-over. The rehabilitation included the replacement of the complete turbine generator unit, electrical and hydraulic control equipment, excitation and protection system, installation of a new transformer and auxiliary power supply and the replacement of the trash rack cleaning machine, head regulator gate and corrosion protection in the penstock, all under the responsibility of Pöyry as the main contractor.