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The energy group ČEZ is preparing one of the most significant modernization projects in Czech hydropower in the last decade. A large pumped-storage hydroelectric power plant is planned for the Orlická dam, which, upon completion, will become the fourth facility of its kind in the Czech Republic. The general director and chairman of the board of ČEZ, Daniel Beneš, presented the project today in Solenice, near Příbram. According to ČTK, the modernization is expected to cost eight billion crowns, with the construction phase starting in 2027 and completion planned for 2033.

The new facility will not involve the construction of a completely new dam. ČEZ intends to utilize the existing hydroelectric power plants of Orlík and Kamýk, which already form an important part of the Vltava cascade. The principle of a pumped-storage power plant is simple: during periods of excess electricity in the grid, water is pumped from the lower Kamýk reservoir back to Orlík. When energy is needed, the water flows in the opposite direction through turbines, generating electricity.

According to available information, the system will be able to store up to 750 MWh of energy at a time, which ČEZ compares to the consumption of approximately 80,000 Czech households in one day. The project is intended to function as a large energy storage battery, which will help stabilize the grid during a period of increasing renewable energy sources.

The current Orlík hydroelectric power plant is one of the most important sources of electricity in the Czech Republic. According to official ČEZ data, its capacity is 364 MW, while Kamýk has a capacity of 40 MW. ČEZ also states that Orlík can reach its full capacity of 4 × 91 MW in just 128 seconds, or less than two minutes. The power plant has supplied over 21 billion kWh of emission-free electricity to the grid in over sixty years of operation.

ČEZ currently operates three large pumped-storage power plants in the Czech Republic: Dlouhé Stráně, Dalešice, and Štěchovice II. After modernization, Orlík will join them, but its advantage is the use of existing infrastructure. Kamýk also plays an important role, as it, according to ČEZ, serves to regulate the fluctuating outflow from the Orlík power plant and enables its peak operation.

According to available information, the general contractor for the project is Litostroj Engineering from the Wikov Group. Two of the four turbines at Orlík are to be converted to reversible turbines. Orlík will therefore remain partly a conventional hydroelectric power plant and partly a pumped-storage source, which will respond to fluctuations in electricity production and consumption.

gnews.cz - GH

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