The derivate Yerevan HPP of 44 MW is located within the the city of Yerevan in the gorge of the Hrazdan River and has been in operation since 1962. The HPP is the first stage of the Sevan-Hrazdan cascade of HPPs.
The hydro scheme includes: rock fill dam, reservoir, idle spillway, water intake, sanitary irrigation water outlet, pressure tunnel, surge tank, turbine water conduit, powerhouse and tail race channel.
Within the HPP`s headworks rehabilitation, I-Energy Power Expert Consulting Inc. performed:
Works on the electrical part: modernization of existing hydro generators (including modernization of the stators and rotors, repair of upper brackets, holding-down gears, supporting structures, thrust bearings and pilot bearings, as well as generators cooling and ventilation systems), replacement of generator excitation systems, rehabilitation/replacement of 6.3 kV cell equipment, replacement of high-voltage/low-voltage power and control cables, replacement of low-voltage AC and DC systems, replacement of control automation and protection system, central alarm system, fire alarm and fire suppression systems for buildings, cable spreading rooms and tunnels, telecommunications, replacement of the charging unit, replacement of the grounding system, overhaul of the bridge crane, overhaul of power transformers 1 and 2, supply of laboratory instruments, spare parts and special tools, recommendations for on-site personnel training programs, the provision of technical documentation (installation, operation, maintenance manuals, detailed drawings, etc.);
Works on the mechanical part: complex replacement and supply of a butterfly valve, bypass, speed control system, 8 atm compressor, internal and external drainage systems, technical water supply system, rehabilitation of a pressure tunnel and a diversion channel shield, supply of spare parts and accessories, personnel training and provision of technical documentation;
Works on the construction part: the rehabilitation of the headworks structures (powerhouse and central control rooms, oil facilities, landscaping, retaining wall, exhaust system Nos. 1 and 2, heating, oil receiver, oil conduit and oil collector, electric lighting), diversion channels, construction works for the replacement/rehabilitation of hydromechanical and electrical equipment, furniture, installation of new fire extinguishers for the fire extinguishing system at the headwork structures, additional design works, technical supervision, architectural supervision.