As part of Sayano-Shushenskaya HPP repair and comprehensive overhaul program, the seventh renovated unit (plants unit No. 5) has been put into operation. The production and installation of new hydropower units for Sayano-Shushenskaya HPP, including installation supervision, commissioning and start-up, are carried out by Power Machines OJSC. A total of three new hydropower units with an overall capacity of 1,920 MW were launched in 2013.
Hydropower Unit No. 5 with capacity of 640 MW, which had been one of the units that sustained the least damage during the accident, was repaired with the assistance of Power Machines employees within 5 months from the Sayano-Shushenskaya HPP accident and put back into operation as early as in March 2010. After two years in operation, the unit was shut down for renovation, i.e. replacement of main components with new ones. The renovation project included a full-scope examination of the turbine flowpath and upstream pipeline, installation of stabilizing ribs in the suction pipe, installation and adjustment of main and auxiliary equipment, as well as of automatic control and protection, excitation, vibration and thermal control, technical water supply, fire-protection, ventilation, oil and air supply systems. During the installation special attention was paid to the quality of the execution of main process operations: the hydropower unit equipment was put through all necessary tests and safety checks at each interim step of the renovation process.
Before Hydropower Unit No. 5 was put into operation, a series of commissioning and start-up tests had been carried out. It included comprehensive individual testing of the unit's equipment and systems, turbine no-load tests, network tests and a 72-hour comprehensive trial run to check the unit's equipment and systems operation under load. All the tests were performed in accordance with a program developed by Power Machines OJSC, and all process parameters were continuously monitored. Based on the results, members of the working committee including representatives of RusHydro OJSC, Power Machines Group, Lenhydroproject OJSC (the project's general designer), Sayanogorsk municipality and the Chief Directorate of the MES of Russia in the Republic of Khakassia signed an act authorizing commissioning of the unit.
At present the operating capacity of Sayano-Shushenskaya HPP is 4,480 MW. Hydropower units Nos. 1, 5, 6, 7, 8, 9 and 10 are in operation. Hydropower units Nos. 3 and 4, repaired in 2010, have been shut down to replace their main and auxiliary equipment. These units are planned to be put back into operation in March and June 2014, respectively.