Vorotan Cascade

Spandaryan HPP building

The Vorotan Complex (Armenian: Որոտան) is a cascade on the river Vorotan in the region of Syunik, Armenia. It is built to produce hydroelectric power and provide irrigation water. The complex consists of three hydroelectric power plants and four reservoirs. It is one of the main power generation complexes in Armenia.

History

Angeghakot reservoir

The design work of the Complex began in 1954 and it was constructed between 1961 and 1989. The first station, Tatev HPP was completed in December 1970, the second one, the Shamb HPP in 1978, and finally the last one named Spandaryan HPP in 1989.^[1]

In 2015, ContourGlobal purchased the Vorotan Complex for US$180 million.^[2] The new owner of the complex is Ara Hovspeyan, who is the Armenian representative of ContourGlobal. ContourGlobal has started a six-year refurbishment program to modernize the plants and improve their operational performance, as well as safety, reliability, and efficiency, with the total investment of $70 million. Although there were several complaints regarding to the sale of the Spendarian Reservoir, which leads to the annual loss of 160 cubic metres (5,700 cu ft) of water of Lake Sevan, the Public Services Regulatory Commission has approved the tariff plan for the consistent exploitation of the Vorotan Cascade by ContourGlobal. This is the biggest investment US investment in Armenia. The project aims to enhance electricity supply reliability and strengthen the country’s power sector. The International Finance Corporation, a member of the World Bank Group, did 20% of the total investment.

Specifications

Vorotan River has length of 178 kilometres (111 mi), the fall of 1,223 metres (4,012 ft), and the natural annual flow of 18.6 cubic metres per second (660 cu ft/s) for the link of Tatev. The source of the river is on 3,045 metres (9,990 ft) of the height and starts like a stream, accepting numerous ponds and streams. The Spandaryan Reservoir in the vicinity of Tsghuk and Gorhayq villages, is the starting point of the complex. From there the water flows to the Spandaryan HPP through a pressurized tunnel. From the Spandaryan HPP the water flows to the Angeghakot Reservoir and continues its journey to Tolors Reservoir which is located in the area of Sisyan and Ayri. From that reservoir the water flows to the Shamb HPP. The reservoir that was constructed beyond the Shamb HPP, the Tatev Reservoir, has a unique architectural structure called "Daisy". From this reservoir the water reaches the regulation pool, from where it proceeds to the Tatev HPP via a turbine pipe.

There are three power stations in the Vorotan Complex.^[3] The Tatev HPP has installed capacity of 157.2 MW, the Shamb HPP has installed capacity of 171 MW, and the Spandaryan HPP has installed capacity of 76 MW.^[1] Total installed capacity of Vorotan Cascade is 404.2 MW and it generates 1.16 GWh of electricity annually.

The highest pressing station is the Tatev HPP. The turbine in the shape of a ladle is the unique feature of this system. The price of 1KW/h electricity produced in the power plant is the lowest in Armenia. The water stores of the Vorotan Complex are also used for irrigation in nearby village and town areas. System consists of four storage lakes: long-term, seasonal, for daily regulation and weekly regulation.

References