South harbour Aarhus: Optimal supply for visionary urban growth

In the South Harbour district of Aarhus, Denmark's second-largest city, a new heating transmission line from the Aarhus Heat Plant to Sydhavnsgade was successfully implemented to support major urban development and ensure reliable heat supply. The transformation of the old coal-crane track area has been a key part of this project, turning it into Aarhus' version of New York’s Skyline. The district, once home to old railway tracks, cobblestone streets, and historic industrial buildings, has been preserved and integrated into a modern commercial area, now offering 6,500 workplaces, vibrant urban life, and space for the socially vulnerable. 

To accommodate this urban development, which also included new parking structures and additional construction, the district heating transmission line was rerouted, and its size increased from DN450 to DN600. The transmission line was co-excavated alongside the DN400 distribution line, which now connects the new business area. For this project, ISOPLUS handled pipe delivery, design, static dimensioning, and on-site problem-solving during installation. 

By using a pre-insulated pipe system with optimized insulation in both transmission and distribution lines, AffaldVarme Aarhus, the utility company in charge, ensured a reliable heat supply with minimal heat loss and optimal efficiency.

ISOPLUS provided approximately 1,200 meters of pre-insulated pipes for the transmission and distribution lines, which now run from the Aarhus Heat Plant, past JyllandsPosten’s new office building, below the railway track, past Kohalen, and along the slaughterhouse to Sydhavnsgade. Throughout the project, ISOPLUS was responsible for pipe supply, planning, and static design, overcoming various installation challenges. In certain areas, pre-insulated steel pipes with reduced jacket pipe dimensions were installed to respect the historic buildings and safeguard existing sewers. One critical aspect of the project was avoiding deep excavations near Kohalen, a slaughterhouse dating back to 1907, now a popular restaurant serving traditional Danish cuisine. 

In addition, ISOPLUS manufactured custom curved DN600 pipes, installed along the railway track using a high-tech hydraulic curving tool. This method preserved the foam insulation, alarm wires, and outer jacket pipe, ensuring insulation values remained intact and the pipe system’s technical lifespan extended to 30-50 years.

Given the high-water temperatures exceeding 110°C, the pre-insulated pipes used for the transmission line, as well as other installation components, were CE-labeled in accordance with the Pressure Equipment Directive (PED). The pipes met stringent requirements for material quality, safety, documentation, and control, as specified by the Danish Working Environment Authority’s regulations.