Zeppelin Power Systems equips Stadtwerke Duisburg with large heat pump

Decarbonizing heating networks through the use of heat pumps

The heat generated by the iKWK plant is equivalent to the heat demand of 4,000 households connected to the existing district heating network. As an innovative CHP plant, at least 35% of the reference heat, based on the total output of the plant, must come from renewable sources. This reference heat is obtained from the effluent of the Duisburg wastewater treatment plant.

Up to 520 m3 of treated wastewater per hour is available to the heat pump as a heat source - at a temperature between 8 and 25 °C, depending on the season. The wastewater is heated by up to 5%. The wastewater is cooled by up to 5 Kelvin. Depending on the operating conditions, this corresponds to approximately 3 MW of regenerative thermal power. The heat pump system then supplies the district heating network with a heating capacity of approx. 4 MWth at a flow temperature of >75°C. The electrical drive energy (approx. 1MWel) of the heat pumps is included in the total heat output with almost no losses. By extracting heat from the purified water of the wastewater treatment plant, cooler water flows into the Rhine and counteracts the additional warming of the river. The system is therefore an asset for low-emission heat generation and makes an important contribution to environmental protection and the decarbonization of heating networks.

"Heat pump systems will play an important role in the decarbonization of local and district heating networks in the future. We are very pleased to be able to realize a reference plant of this size together with Stadtwerke Duisburg. The construction of heat pump systems will play an increasingly important role in our business in the future," says Daniel Schäfer, sales engineer and project manager at Zeppelin Power Systems.

Heat turnaround in Duisburg: Stadtwerke Duisburg builds world's largest cogeneration plant at a wastewater treatment plant

The special feature of an innovative cogeneration plant is that, in contrast to a conventional cogeneration plant, it must be combined with renewable heat, e.g. from solar thermal energy, or with a heat pump. The components of the iKWK plant will be built in Huckingen and at the headquarters of Stadtwerke Duisburg on Bungertstraße. A total of two cogeneration modules will be built, each with an electrical output of 4.5 MW and a thermal output of 4.5 MW. In addition to the two CHP units (1) and the heat pump system (2), the electrode boiler is the third (3) component of an innovative CHP system for district heating generation. The boiler will be used to convert excess electricity into heat.

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