Largest waste heat project in NRW: Green Heat goes into operation
Gelsenkirchen, 16th December 2025 - The heat transition in the northern Ruhr region continues to gather pace. In Gelsenkirchen, the district heating provider Iqony has now put a plant into operation that makes industrial waste heat usable for district heating on a large scale for the first time.
At the centre of "Green Heat", the largest waste heat project in North Rhine-Westphalia, is the extraction of industrial waste heat from refinery plants at Ruhr Oel GmbH in Gelsenkirchen-Scholven. In this way, up to 50 megawatts of heat output can be provided in future and the equivalent of around 30,000 households in the northern Ruhr region supplied with district heating. This will save up to 60,000 tonnes of CO₂ per year.
Eight heat exchangers, a transfer station and an extensive infrastructure with steel construction and pipework were built over a three-year construction period to extract the waste heat. The new pipe route, which is almost three kilometres long and mainly underground, connects the waste heat sources with a new pump house on the site of the Scholven power plant. There, the heat is fed into Iqony's district heating network. The 24/7 trial operation has been running at a stable 20 megawatts for a few weeks now; the total output is set to increase to over 50 megawatts by 2026.
Combining security of supply and climate protection
"Green Heat shows how consistently we combine security of supply and climate protection," says Dr Andreas Reichel, CEO and Labour Director of the Steag Iqony Group. "We are tapping into a previously lost energy resource - and making it an important driver of the heating transition."
With a network length of 2,186 kilometres and around 4,500 GWh of heat generation per year, Steag Iqony is one of Germany's leading district heating providers. Around half of the heat generated already comes from climate-neutral sources - with Green Heat, this proportion will increase further.
"With Green Heat, we are making district heating in the northern Ruhr region cleaner and more resilient," emphasises Nikola Feldmann, Managing Director of Iqony Wärme, the subsidiary responsible for the project. "The project was technically challenging, but is a valuable benefit for tens of thousands of households," adds Managing Director Christian Hillmann.
