The Czech Republic will gain its fourth large pumped storage hydropower plant by 2033 after energy company ČEZ announced plans to modernise the Orlík hydropower plant and convert part of the facility to reversible operation.
The project will see two of Orlík’s four generating units converted into fully reversible pumped storage units, allowing water to be pumped from the downstream Kamýk reservoir back into the Orlík reservoir for energy storage. The upgraded plant will be able to store up to 750 MWh of electricity in a single cycle, equivalent to the daily consumption of around 80,000 Czech households.
The Orlík hydropower plant, part of the Vltava Cascade, completed construction more than six decades ago. Its fourth and final generating unit entered operation 63 years ago.
“Our government has set clear priorities for the energy sector. Alongside the development of zero-emission power generation, these include strong support for energy storage,” said Minister of Industry and Trade Karel Havlíček.
“Our pumped storage hydropower plants have delivered decades of reliable operation and continue to play a key role in the stability of the Czech energy system every day. The last pumped storage hydropower plant in the Czech Republic was built in the mid-1990s, and Dlouhé stráně has since become one of the country’s symbols of water-based energy storage.”
He added: “Today, thirty years later, we are beginning work on a new pumped- facility, and I am confident that the new Orlík installation will serve Czech energy needs reliably and well.”
ČEZ CEO and chairman Daniel Beneš said the company had decided to preserve Orlík’s role in the Czech power system while adding energy storage capability.
“Orlík is a key element of the Vltava Cascade and plays an important role in managing the national power system,” Beneš said. “We have decided that it will continue to serve for decades to come, now also as a large-scale battery.”
He noted that the 70m elevation difference between the Kamýk and Orlík reservoirs made the project feasible and highlighted that the conversion would be carried out within the footprint of the existing facility.
“One key advantage of this new pumped-storage plant is that it will be built within the footprint of the existing facility, eliminating the need to occupy additional land. It will therefore be both efficient and environmentally friendly,” he said.
Beneš added that the project would be completed in stages so that at least two of Orlík’s four generating units remain in operation throughout the modernisation programme.
Engineers will modernise all four generating units while maintaining the plant’s total installed capacity of 364MW. Two conventional units will continue operating with a combined output of 190MW, while the two reversible units will provide 174MW of pumped storage capacity.
The main phase of the modernisation is scheduled to begin in 2027, with commissioning of the pumped storage facility expected in 2033. Once completed, the project will increase the Czech Republic’s pumped storage capacity by more than 12%.
ČEZ is developing the project in cooperation with the Vltava River Basin Authority, which owns the reservoir.
“We support the Orlík pumped-storage project and have been engaged in long-term discussions with ČEZ on its development,” said Petr Kubala, CEO of the Vltava River Basin Authority. “For us, it is essential that the plant modernisation and conversion do not require any major structural interventions in the dam itself, nor any changes to the operating water levels defined in the Operating Rules.”
Kubala added that the project would not require land acquisition and would not affect recreation, navigation or fishing activities.
The project is also being supported by Czech engineering company Wikov Group.
“The Orlík transformation project is clear proof that Czech engineering and technical expertise are world-class,” said Martin Wichterle, chairman of Wikov Group. “We greatly appreciate ČEZ’s trust and are proud to be part of this unique project.”
According to ČEZ, Orlík will become the largest project in the history of modern Czech hydropower. The company has previously modernised around 40 generating units at more than 20 hydropower plants across the country, including Lipno, Dlouhé stráně, Slapy, Kamýk, Mohelno and Dalešice.
ČEZ said investments of around CZK5 billion in hydropower modernisation have improved turbine efficiency by between 4% and 10%, depending on the plant and turbine type, and have prepared its hydropower fleet for continued operation over the coming decades.
