Lifting of the 35-megawatt electrode boiler: Unique power-to-heat project at the Leuna chemical site reaches a decisive milestone

At the Leuna chemical site, the power-to-heat project by InfraLeuna and 50Hertz, which is unique in Europe, is progressing rapidly. With the successful delivery and installation of the 35-megawatt electrode boiler, a key milestone has now been reached. The boiler forms the heart of the innovative plant, which will convert electricity from renewable energies into steam in the future, thereby supplementing the existing steam generation in a climate-friendly manner. This technology will achieve a pressure level of 47 bar(g) for the first time in Europe.

Heavy transport with precision

After months of preparation, the Inopower electrode boiler arrived at the Leuna chemical site by heavy transport on November 3. The 33-ton component was lifted with millimeter precision into the prepared steel structure on the site of InfraLeuna's gas and steam turbine power plant 2 using a special crane from Mammoet Deutschland GmbH in cooperation with plant constructor Etabo Energietechnik und Anlagenservice GmbH. “The lifting of the boiler is an impressive technical moment – and a visible sign that our project is progressing according to plan,” said Dr. Christof Günther, Managing Director of InfraLeuna GmbH. "With the lifting of the electrode boiler, a plan is now becoming a tangible reality. This project is the first power-to-heat project in Leuna and a milestone on our path to making the chemical site sustainable for the future."

The lifting of the boiler is part 2 of a complex project. Since the boiler could not be brought into the building from any side at reasonable expense, it was decided to lift it in via the roof. In August, a partially operational double chimney system was converted or dismantled in preparation for the project so that the space required for the installation could be created.

Another step towards climate-neutral industry

The new plant will be capable of supplying up to 45 tons of steam per hour at parameters previously unattainable with electrode boilers: 47 bar(g) and 320 °C. The steam generated will be fed into InfraLeuna's existing high-pressure steam system and made available to local chemical companies. InfraLeuna's power plants can be scaled back whenever the boiler absorbs electricity and converts it into thermal energy. This means that as the proportion of renewable electricity increases, the use of natural gas can be reduced.

By utilizing surplus electricity from renewable energies, the project contributes to grid stability while significantly reducing CO₂ emissions at the site.

Dr. Dirk Biermann, COO at 50Hertz: "The installation of the electrode boiler is a real milestone – not only for the project, but also for the energy transition in industry. Together with InfraLeuna, we are demonstrating how renewable energies and industrial processes can be brought together in a meaningful way. The project in Leuna is a prime example of how we can ensure grid stability while significantly reducing CO₂ emissions."

Project progress and outlook

With the boiler now in place, the heart of the plant is in position, heralding the start of the main assembly phase. The installation of the piping and cable trays, including their assignment, will follow in the coming weeks.
Cold commissioning of the power-to-heat plant is still scheduled for February 2026, with the aim of bringing the plant into continuous commercial operation by May 2026. It can then be integrated into the grid control processes at 50Hertz. It is owned and operated by InfraLeuna, which markets and exploits it commercially on its own responsibility. At the same time, 50Hertz has priority access rights to use the plant for grid stabilization when necessary.

Background: The Leuna power-to-heat project

InfraLeuna GmbH and grid operator 50Hertz Transmission GmbH are jointly implementing the first large-scale power-to-heat plant at this pressure level at a chemical park in Europe. The contract was signed by both parties in February of this year. The plant has an electrical and thermal output of around 35 megawatts each, which means that surplus wind or solar power can be converted directly into process steam. At the Leuna chemical site in particular, where large amounts of thermal energy are required, the technology enables a significant reduction in CO₂ emissions while also strengthening the resilience of companies to volatile energy markets.