TRIMET will now feed approximately 31,000 megawatt-hours of unavoidable waste heat annually from the process heat of its electrolysis furnaces into Iqony's district heating network, which supplies customers in Bottrop, Essen, and Gelsenkirchen. This amount covers the calculated demand of more than 5,500 households.

"With this project, TRIMET and Iqony demonstrate what circular economy means in practice in an industrial nation. Instead of letting industrial waste heat dissipate unused, it is being reused in heating networks. Waste heat is a key building block for decarbonizing heat supply. Our customers in the Ruhr region already benefit from district heating that relies almost 70 percent on carbon-neutral sources – thanks in large part to the use of waste heat. The heat cooperation with TRIMET makes our district heating even more future-proof," says Matthias Ohl, Managing Director of Iqony Fernwärme.

"The fact that we are now heating thousands of homes with the waste heat from our facilities is a milestone for our company and for the region," says Dr. Andreas Lützerath, Member of the Executive Board of TRIMET Aluminium SE. "This clearly shows how innovation drives the green transformation. By making aluminum production more flexible, we are moving closer to climate protection targets, strengthening the future viability of our production sites, and working together with Iqony to make an important contribution to energy security."

Million-Dollar Investment in Climate-Friendly Heat

The use of industrial waste heat became possible because TRIMET had converted aluminum production to flexible adaptation to the fluctuating power supply from wind and solar systems. Heat exchangers specifically installed on the electrolysis furnaces capture the heat from the production process. Four ventilator stations direct it through a tube bundle with water, which is heated to around 130 degrees Celsius. Under high pressure, the water reaches an energy center via a pipe system, where it transfers its heat to the water in the district heating network. TRIMET installed a 1.6-kilometer pipe system on the plant premises in which 36 cubic meters of water circulate. Iqony laid approximately 700 meters of connecting pipeline linking the energy center with the connection point outside the plant premises.

In 2023, TRIMET and Iqony agreed on a 20-year cooperation for the use of waste heat from aluminum production at the TRIMET site in Essen. Just over two and a half years later, work to establish the infrastructure for converting the production facilities has been completed. Following completion of trial operations, the facility will soon enter regular operation. Both companies have invested a total of several million dollars in the project.