Europe-wide unique power-to-heat project at the Leuna chemical site

The grid operator 50Hertz Transmission GmbH and InfraLeuna GmbH have signed a contract for the construction and operation of a power-to-heat (PtH) plant at the Leuna chemical site in the presence of Prof. Dr. Armin Willingmann, Minister for Science, Energy, Climate Protection and the Environment of the State of Saxony-Anhalt. The plant will convert green electricity from wind energy and photovoltaic systems into process steam in accordance with the “use instead of curtailment” principle.

InfraLeuna will plan, build and operate the plant, while 50Hertz will cover the investment costs of 13.6 million euros and include it in the management of electricity grid bottlenecks. Instead of curtailing wind or solar plants, in future surplus green electricity can flow into the PtH plant and be converted into process steam.

The innovative PtH plant consists of an electrode boiler with an electrical and thermal output of approx. 35 megawatts each, in which water is heated by electricity. Every hour, 45 tons of superheated process steam are generated and fed into the chemical site's steam network. The pressure level of 47 barü achieved here is the first time this technology has been used anywhere in Europe.

Prof. Dr. Armin Willingmann, Minister for Science, Energy, Climate Protection and the Environment of Saxony-Anhalt: “We need intelligent technological solutions for a successful energy transition. The construction of the power-to-heat plant here at the Leuna chemical site is an important building block for a climate-friendly industry in Saxony-Anhalt. In future, electricity that would otherwise have to be curtailed will be converted directly into heat and used. Especially in times of high energy prices and the need to become less dependent on fossil fuels, projects like this show how we can successfully combine economic competitiveness and climate protection. At the Leuna chemical site in particular, where large quantities of thermal energy are required, the technology enables a significant reduction in CO₂ emissions and at the same time strengthens the resilience of companies to volatile energy markets. The Leuna chemical site is one of the pioneers when it comes to sustainability. It has been working intensively on the transformation of the chemical industry for a long time - towards renewable energies and renewable raw materials. The power-to-heat plant fits in very well with this profile.”

After more than two years of concept work, implementation is now underway.

“The electrode boiler with the previously unattained parameters of 47 barü and 320 °C is tailor-made for our high-pressure steam system. In combination with our highly flexible gas and steam turbine power plants, we are creating a uniquely responsive energy system in Leuna,” explains Christof Günther, Managing Director of InfraLeuna.

InfraLeuna's power plants can be shut down whenever the PtH plant takes in green electricity and converts it into thermal energy. In this way, the use of natural gas can be further reduced as the proportion of electricity generated from renewable sources increases and a major step can be taken towards CO₂ neutrality at the site.

Construction is scheduled to start in the middle of this year, with commissioning expected in the first quarter of 2026.

“This boiler will help us, especially in the current very tense situation in the chemical industry. With this forward-looking power-to-heat project, we are reducing grid bottlenecks, using surplus electricity, saving valuable natural gas and ensuring a reliable supply of process steam for our customers at the Leuna chemical site,” says Christof Günther.

Dirk Biermann, Managing Director Operations (COO) at 50Hertz: “Our 50Hertz system management near Berlin can use the PtH plant for congestion management. This relieves the electricity grid twice over - through additional electricity consumption in the power-to-heat plant and simultaneously lower electricity and heat production in the power plant. Instead of paying compensation for electricity that is not produced, this plant provides us with an effective tool for maintaining system stability. The central German region offers good conditions for this concept, as there are central heat supply systems as well as a high volume of wind power and now also large ground-mounted solar plants. In order to alleviate grid bottlenecks in the future, the expansion of the electricity transmission grids is the most important measure required. This must be supplemented by various storage systems; PtH systems in industry and in municipalities with district heating networks and, if necessary, heat storage systems can also contribute to this.”