ČEZ to invest over CZK 400 million in Czechia's Dlouhé stráně pumped-storage plant this year

ČEZ energy group will invest more than CZK 400 million this year in repairs and modernisation at the pumped-storage hydropower plant Dlouhé stráně in the Šumperk region, almost four times as much as last year. ČEZ plans to invest slightly more at Dlouhé stráně next year. The investment is part of the gradual renewal of key components of the turbine-generator units, which are nearing the end of their service lives after almost 30 years of operation. Róbert Heczko, director of ČEZ's hydropower plants, told journalists today.

According to Heczko, the investments, worth hundreds of millions of crowns, will ensure reliable operation of the Dlouhé stráně plant, which serves as a huge energy storage facility. In the Czech power system, it plays a role both when surplus energy is used to pump water from the lower reservoir to the upper one and when energy is in short supply, in which case the plant generates electricity and sells it at a higher price. The plant is playing an increasingly important role in balancing unstable supplies from renewable energy sources.

„We recognise the importance of Dlouhé stráně and regularly invest in improving the plant's operational reliability and safety. This year and next, we will carry out important upgrades to the equipment in both units. But the work will certainly not end there: after 2030, further and even more significant investments await us,“ Heczko said, adding that both reservoirs are also due to be reconstructed after 2030.

This year's main investment is focused on the TG2 turbine-generator unit. Technicians will, for example, replace the stator winding and realign the entire unit, upgrade the control system, repair the hydraulic motors and apply new internal coatings to the water conduits from the upper reservoir to the turbine. This year's investment plan also includes repairs to the bridges on the road leading to the upper reservoir and the installation of a stationary crane at the lower reservoir to improve safety.

„We will be repairing a large part of the unit, which means we have to lift the stator and rotor into position, onto specially reinforced areas in the turbine cavern. Repairing the shaft will also be technically demanding; it will be done on a lathe in Plzeň,“ said Ludvík Štrobl, director of the Dlouhé stráně plant.

The shaft, which will be dismantled into two sections weighing 28 tonnes and almost 33 tonnes, will be transported to Plzeň on specially modified tractor units.

Repair and modernisation work at the Dlouhé stráně plant began in early April and will continue until January next year. Dozens of employees from several Czech companies will take part. The reconstruction will require the plant to be shut down from 19 August to 20 September, when the TG1 turbine-generator unit will also be taken offline.

The Dlouhé stráně pumped-storage plant has been in operation since 1996, and its output has risen in recent years. The power facility has long attracted tourists to the mountainous region, which is heavily dependent on tourism. Visitors can tour the plant's underground workings or enjoy the view from its upper reservoir.