A heavyweight for Jochenstein: 62 tonnes safely transported across the Danube

On 6 October, the first of five new transformers arrived at the Donaukraftwerk Jochenstein. Following the heavy-haulage transport, a floating crane took over for the final stage, safely transporting the 62-tonne transformer across the Danube to its final location.

The heavy-haulage transport travelled along the Austrian side to the power plant. There, the transformer was unloaded and transported across the Danube to the screen platform using a VERBUND floating crane. Following this, the crane safely positioned it in its final location.

The transport vehicle measured an impressive 30 metres long, 3.5 metres wide and 4.4 metres high; the combined weight of the low-loader and the transformer was around 122 tonnes. The transformer itself measures approximately 6.5 by 3 by 4 metres. The VERBUND floating crane stationed on site, with a maximum lifting capacity of 100 tonnes, was used for the lift.

The lift was something special even for VERBUND’s experienced operations team. The floating crane dates back to when the power plant was built and is still in use today. A gantry crane – which is standard for run-of-river power plants – is not feasible due to the architecture at Jochenstein. “The crane has no drive of its own – we move it sideways using winches and pre-tensioned ropes. We use a water ballast to precisely adjust its position until the transformer is in exactly the right place, down to the milimetre. This requires a great deal of experience and excellent teamwork,” says Site Manager Manfred Hackner.

The delivery forms part of the comprehensive rehabilitation of Donaukraftwerk Jochenstein. As part of this project, five new turbines are being installed, along with five new transformers, each of which requires its own enclosure due to the presence of a water mist fire-suppression system. The necessary replacement of the 220 kV energy dissipation cables is also technically challenging, as the long cables have to be routed over the lock bridge in confined spaces.

The Jochenstein power plant, built between 1952 and 1956, is currently undergoing extensive modernisation to bring it up to the latest technical standards and adapt it to the changing conditions brought about by climate change. New turbines are designed both to make more efficient use of high water flows and to enable flexible operation when water levels are low. As a result, turbine capacity will increase by 8 megawatts to 140 megawatts, and the mean energy capability will increase by 55 gigawatt-hours to 905 gigawatt-hours.

The rehabilitation programme will run from 2023 until the end of 2030. VERBUND is investing around 61.4 million euros in the project.