Construction of the Nizhne-Chatkalskaya HPP continues near Tashkent
Uzbekistan continues to implement a large-scale program to increase the share of renewable energy sources in the national energy balance, where hydropower occupies one of the priority places. As part of this strategy, Uzbekhydroenergo Joint Stock Company is building the Nizhne-Chatkal HPP on the Chatkal River in the Bostanlyk district of the Tashkent region. Media representatives were able to find out about the progress of work on this investment project, approved by the resolution of the Cabinet of Ministers of Uzbekistan dated January 31, 2020, during a press tour organized by the company on May 23.
According to the project data provided by Uzbekhydroenergo, the future HPP will be equipped with four hydroelectric units with a capacity of 22.5 MW each. Thus, the total installed capacity of the station will reach 90 MW, and the estimated annual electricity generation will be 300 million kilowatt-hours. The company estimates that this volume will be enough to supply up to 125 thousand households. The launch of the station, as stated, will allow saving significant amounts of fossil fuels annually.: about 81 million cubic meters of natural gas or 250 thousand tons of coal.
The key feature of the project, according to Uzbekhydroenergo, is the use of advanced dam construction technology from rolled compacted concrete (RCC). It is claimed that this technology is being used for the first time not only in Uzbekistan, but also in Central Asia. The dam with a height of 60 meters, a length of 270 meters and a width of 7.5 meters will create a reservoir with a volume of 6.8 million cubic meters. The use of RCC technology, according to assurances, reduces the project implementation time by half due to the high strength of concrete, its low water permeability and the possibility of mechanized laying. The project documentation is being developed by JSC “Gidroproekt” with the participation of engineering companies from Turkey and Iran. Modern equipment is involved in the construction, including the equipment of the German company GERTEK for automated supply of cement mortar.
Representatives of Uzbekhydroenergo assure that the station is designed in such a way as to minimize the impact on the aquatic ecosystem, not to violate the hydrological regime and not to negatively affect the state of the environment. However, the construction of large hydroelectric power plants, especially associated with the creation of reservoirs, traditionally raises serious questions among environmentalists and experts about the long-term consequences. Such projects can lead to changes in riverbeds, biodiversity reduction, land flooding and affect water quality. The assessment of the real environmental impact of the Nizhne-Chatkalskaya HPP will certainly require long and careful monitoring after the facility is put into operation, since the environmental consequences are not always obvious at the design and construction stage.
Uzbekhydroenergo also reports on other technological innovations: a cement curtain is being formed to increase the water resistance of the dam, and the construction of a tunnel with a length of more than 650 meters has been completed. The materials extracted during excavation are processed on site and used for the production of RCC concrete at its own installation. For the first time in Uzbekistan, particularly durable concrete of the M800 brand is used in the flushing gallery of the structure, and its bottom part is lined with wear-resistant metal plates. The quality control of the works is carried out using the equipment of the Italian company MATEST, and the concrete is supplied by a modern belt conveyor system – a technology used only in a few countries of the world, including the USA, Canada, Italy, Iran and now Uzbekistan. It is emphasized that up to 90% of components and technological equipment for HPPs are supplied by domestic enterprises that are part of the structure of Uzbekhydroenergo.
The commissioning of the Nizhne-Chatkalskaya HPP is scheduled for the celebration of the Independence Day of the Republic of Uzbekistan on September 1.
Alexander Eskendirov (Rivers.Help!)
Original (in Russian): Рядом с Ташкентом продолжается возведение Нижне-Чаткальской ГЭС
