The Toktogul hydropower plant (HPP), with an installed capacity of 1.2GW, is the biggest power plant in Kyrgyzstan accounting for approximately 40% of the country’s power output.
The plant enables power export to the neighbouring countries and provides frequency regulation services to the Central Asian power system.
It is currently undergoing rehabilitation and upgrade to ensure safe, efficient and reliable operations by modernising the ageing infrastructure that dates back to the 1970s.
The plant’s owner and operator Open Joint-Stock Company Electric Power Plants (EPP) is implementing the upgrade in three phases.
All the four turbine generator units of the plant are being refurbished to increase the total generating capacity by 240MW to 1.4GW. The refurbishing works were commenced in 2012, with completion targeted for 2023.
The modernisation project will help to power approximately 200,000 additional households while increasing the plant’s lifespan by 35 years. It will also complement the country’s plan to export surplus electricity during summer to Afghanistan and Pakistan through the CASA-1000 power transmission line.
Toktogul hydropower plant details
The Toktogul hydroelectric facility is located near the city of Toktogul in the Jalal-Abad Region of Kyrgyzstan. It is a high-pressure hydroelectric power station that includes a 215m-high concrete gravity dam on the Naryn River.
Toktogul reservoir is approximately 65km-long and has a total capacity of 19.5 billion cubic metres. It is one of the biggest reservoirs in Central Asia.
The dam construction was started in 1960 and the power plant was brought online in 1975. The plant generates approximately 6,000GWh of electricity a year using four vertical Francis turbines of 300MW each. The first two turbines were commissioned in 1975, while the third and fourth units were put into operation in 1976.
Toktogul HPP rehabilitation project
The Toktogul hydropower plant's rehabilitation was identified as the highest priority to ensure Kyrgyzstan’s energy security as the plant’s availability started declining drastically due to the failure of the ageing components.
Phase one of the rehabilitation project includes replacement of the electromechanical equipment such as generator circuit breakers, excitation, control systems, and the 500kV cable lines.
The second phase will replace the components of units two and four apart from repairs to the auxiliary systems and plant equipment.
The phase three aims to replace the turbine generator units one and three. It will also refurbish the dam’s civil structures and monitoring systems.
The project will increase the generation capacity of each unit from 300MW to 360MW, thereby increasing the efficiency to 92.5%.
The rehabilitated units two and four are expected to start commercial operations by November 2020 and 2021, respectively. The refurbished unit one will be ready for operations by November 2022, while the unit three will be operational from November 2023.
The first phase of the project required financing of approximately £38m ($62m), of which £34m ($55m) was provided by the Asian Development Bank (ADB) through loan and grants and the remaining £4m ($7m) was provided by the Government of Kyrgyz Republic.
Eurasian Development Bank (EDB), through the Eurasian Fund for Stabilization and Development, facilitated a loan of approximately £62m ($100m) for the £155.2m ($251m) second phase rehabilitation project.
ADB provided £68.3m ($110m) and the Government of Kyrgyz Republic provided £25m ($40m) for the second phase.
The phase three rehabilitation works are expected to cost approximately £113m ($175m), which is being financed by ADB (£71.4m), EDB (£25.9m), and the Government of Kyrgyz Republic (£16.2m).
A joint venture of GE Hydro (France) and GE Renewables (Switzerland) was awarded a turnkey contract worth £74.71m ($104m) for the Toktogul hydropower plant rehabilitation project in February 2018.