Stora Enso’s paper mill to provide district heating in Germany

By Stora Enso | January 31, 2020

Excess heat from the industrial processes at Stora Enso’s Maxau paper mill in the south-west of Germany, will be used to provide renewable, biomass-based district heating for the city of Karlsruhe.

A new, approximately 2-kilometre-long connection pipeline will transfer the heat from the mill to an existing pipeline that links up the local refinery with the municipal heating grid. The local district heating supplier Stadtwerke Karlsruhe will start the construction of the pipeline in late 2020, aiming for completion by the end of 2022.

“According to the feasibility study, commissioned jointly by Stadtwerke Karlsruhe and Stora Enso, it proved viable technologically, ecologically and financially to use the excess heat from paper production to provide district heating for our city,” says Olaf Heil, technical managing director at Stadtwerke Karlsruhe.

“We are happy to be part of this extensive environmental project and in this way, boost the ecological sustainability of our processes even further in the future,” says Joachim Grünewald, mill director at Maxau Mill.

More than 80 percent of the fuel used at Maxau Mill is biomass-based. In addition, a new steam turbine, to be taken into use at the mill during 2020, will further increase the potential of combined heat and power production at the mill. Thanks to these factors, the city of Karlsruhe and Maxau Mill expect to cut 10 000 tonnes of CO2 emissions annually.

Roughly 40 000 households and a large number of businesses in Karlsruhe currently use district heating. More than 90 percent of the heat is sourced from industrial processes and from the excess heat generated in combined heat and power production. The excess heat from Maxau Mill will add to current local sources of heat – an oil refinery and a power plant of an energy supplier. This expansion contributes to the German energy transition and is one of the biggest climate protection projects in the state of Baden-Württemberg.