Race against time.
Global Hydro completed the refit of the existing Dunakiliti power plant dam structure on a tributary of the Danube in Hungary in a record-breaking eight months.
Visionary power. Wherever you want.
Race against time! Global Hydro completed the refit of the existing Dunakiliti power plant dam structure on a tributary of the Danube in Hungary in a record-breaking eight months. This upgrade not only strengthens the plant’s contribution to renewable energy generation but also demonstrates Global Hydro's ability to deliver high-performance solutions under challenging conditions and tight timeframes.
The Dunakiliti dam, located in the northwestern border region of Hungary, was originally planned to be part of a large-scale water management and hydropower system. However, construction was halted due to concerns over environmental impacts on the Szigetköz floodplain. Despite this, the dam continued to play a key role in regional water management, and space had already been reserved in the structure for a future hydropower plant. More than 40 years later, that vision has finally become reality - with Global Hydro as a trusted partner in the project’s implementation.
From the outset, the intention was to integrate a hydroelectric power station. When the transverse structure was installed 4 decades ago, space was intentionally left in the first pillar on the left bank for future installation. Although only electromechanical components for a small-scale power plant were initially needed to utilize the existing potential of the weir system, the project was delayed by over a decade due to ecological, nature conservation, economic, and water management concerns for Szigetköz. With a state subsidy nearing expiration and a contract guaranteeing a special tariff, rapid completion became crucial. If the power plant wasn't online by June 30, 2022, the original economic calculations would no longer apply. Despite the pressure, the project team believed meeting the deadline was still possible. With detailed engineering plans in place from the start and strong collaboration among partners operating under the F-Energies holding company umbrella, including Hereschwerke for electrical engineering and Enso for structural expertise, the team was well-equipped to tackle the challenges ahead.
The plant now generates 12 to 14 GWh of green electricity per year, with a Kaplan S turbine seamlessly integrated into the existing power house.
Over the decades, large amounts of sediment had accumulated in the intake and outlet areas of the power plant. To clear the intake, dam beams were inserted, and a small excavator was lowered into the confined space to expose the riverbed. The concrete walls that had sealed off the turbine chamber for 40 years had to be carefully removed to protect the dam beams. To stay on schedule, multiple tasks were carried out simultaneously wherever possible.
Installing the 3.15-meter Kaplan S-type turbine presented a significant challenge. Heavy components, such as the 20-tonne guide runner, had to be precisely positioned using the weir system’s overhead crane. The space was so tight that a few centimeters of the turbine chamber’s roof opening had to be removed to avoid damage. One of the four runner blades even had to be detached and reassembled to fit the turbine safely into place.
Global Hydro were also responsible for implementing the custom-built hydraulic steelwork components. This included dam beams, the intake screen, and a new cleaning machine, which was seamlessly integrated into the overarching HerosControl Plant control system.
Despite the tight deadline, the project required a high degree of flexibility. When flow conditions in the inlet area needed improvement, a solution was quickly found by extending the base of the pillar. CFD calculations confirmed that this modification would significantly enhance the inlet conditions, making it the preferred approach for implementation.
While construction work was ongoing on-site, Global Hydro faced immense time pressure as the general contractor to manufacture the turbine and organize the remaining deliveries - including the generator, gearbox, auxiliary equipment, transformer, and control system. The turbine’s dimensions played a crucial role, as its size was pushed to the limit to maximize the use of hydrological conditions.
The state-of-the-art turbine is designed to discharge a water volume of 54m³/s and drives a water-cooled generator via a vertical shaft in the gearbox, delivering a nominal output of 2.036 MW from a nominal head of 4.3 meters. The 4-blade runner rotates at 120 rpm, translating to 750 rpm via the gearbox, enabling the power plant to supply around 12–14 GWh of clean electricity annually to the 22kV grid, equivalent to the average annual consumption of 5,500 to 6,000 Hungarian households.
The power plant's economic operation is largely due to the successful connection to the grid on schedule, with commissioning completed on June 27, 2022, just three days before the deadline for the subsidized tariff. This technical and logistical achievement was made possible by state-of-the-art technology and the expertise of all involved.
Dunakiliti provides a promising model for future projects, especially in terms of the interaction within the extended group of companies that included Enso and Hereschwerke. The combined expertise of the three companies enables projects to be managed all the way from evaluation and analysis through to final operation. "On a worldwide scale we identified some great potential for investors to benefit from the turn-key optimisation of small hydropower plants. Contractors often lack the technical expertise for hydropower-specific optimisation. That’s where we come in, offering holistic solutions that save time and money”, announces Managing Director Heinz-Peter Knass. He points out that, in this context, the European trend toward realising ‘downsizing potential’ and building as compactly as possible also needs to be implemented elsewhere. Experience and expertise enable him to see that delays and increases in costs for small hydropower projects are often due to the numerous inter-business contact points between construction, planning and operation companies. The group-loop model is expected to enable Global Hydro and its partners to minimise the number of information bridges, and make projects leaner and more economical overall.
Tight deadline? Unique requirements? We adapt to your needs and deliver tailor-made solutions with speed and precision. Contact us today to make your project a success - on time and on target!
Thomas Sageder
Area Sales Manager
+43 7285 514 0044
thomas.sageder@global-hydro.eu Contact