Another 640MW unit has been successfully commissioned at the Sayano-Shushenskaya hydropower plant, JSC Rushydro has announced, adding to the seven units currently in operation at the project.

Unit No.4 was one of the least affected during the fatal accident which occurred at the plant in August 2009. The unit was initially placed back into operation in August 2010 after repair, but was decommissioned two years later for work to replace all the main and auxiliary equipment of the unit, including the turbine, generator, control system, excitation system and various protection systems. The testing program included 72 hours of work under load.

Currently, the working capacity of Sayano-Shushenskaya is 5120 MW with units 1, 4, 5, 6, 7, 8, 9 and 10 in operation. RusHydro plans to launch units 2 and 3 in June and October 2014 respectively, after which the plant will reach its full capacity of 6400 MW.