Danish quality & design since 1921
Innovation in large Swedish district heating project saves time and money. When the town of Sandviken to the north of Stockholm needed to be supplied with district heating from Gävle, two 96 m2 plug-and-play pumping stations were the solution. The reduced complexity promotes the green transition.
The FELIX project is an ambitious Swedish district heating project that will supply consumers in Sandviken with district heating from Gävle. This includes the construction of a 22 km long pipeline that will transport hot water from Gävle to Sandviken via two pumping stations with cold water return as part of the green transition in the region.
According to Gävle Energi, it is Sweden’s smartest district heating pipeline, which has prompted Klimatklivet to provide their largest investment support to date, due to the significant reduction in emissions of CO2 and other gases. Klimatklivet is a support scheme under the Swedish Environmental Protection Agency.
The entire project is worth SEK 450 million, with the cost of the pumping station being SEK 50 million. The project is dimensioned to deliver 70-80 MW, which is the maximum power demand, to the district heating customers in Sandviken.
– “By Swedish standards, it’s quite a large district heating project”, says Per Erdegren, civil engineer, project manager for pumping stations and employee of the consultancy firm ALSA JD-Gruppen.
From the outset, the client Gävle Energi wanted to reduce the complexity of the project and the pumping stations. That’s why they chose to work with a single supplier for the installation of the technology and the construction of the pumping stations. Normally, this would require the creation of a large construction site, but the client decided to think outside the box.
– “The solution was a modular plug-and-play solution, where the two pumping stations are manufactured at a factory in Denmark and installed in so-called technical houses”, says Helena Edström, Head of Sales at Desmi Sweden, the turnkey supplier of the two complete pumping stations.
Each technical house consists of three modules, where the two 4 x 10 metre modules contain the pump module for supplying the hot district heating water as well as the pump module for the return water. The third module is 8 x 2 metres and contains the control technology. The houses and technology are mounted on cast concrete bases. Both pumping stations are dimensioned for DN 400 district heating pipes, and the 4 x 315 kW Desmi pumps, electricity, control technology, insulation, etc. was installed by Priess District Heating at their factory in Herning.
– “It is the largest plug-and-play pumping station we have delivered to date”, says Jacob Holdgaard, District Heating Technical Manager at Priess District Heating A/S.
He adds that the technology is familiar, but at design level, the division of the technical building itself into three modules is new. The modules were transported in two phases by special transport to the final destination between Gävle and Sandviken – a journey of almost 1,000 km.
– “The critical moment is when the 40-tonne modules are lifted into place on the large sand cushion”, says Per Erdegren and adds:
– “This is done to ensure the modules precisely fit the pipes that are brought out of the ground and form the district heating pipeline.”
– “It took seven hours to lift the modules into place and everything fit together”, says a proud Helena Edström from Desmi.
According to Per Erdegren, the strong result was achieved through close collaboration with Desmi and Priess. All challenges were handled along the way to make sure everything was right at installation. The pumping station will now be tested before it is finally put into operation in the fall of 2024, when the new district heating pipeline is complete.
– “This solution with a plug-and-play pumping station is definitely interesting for other district heating plants in Sweden”, says Per Erdegren. He continues:
– “This saves time and avoids the need for a large construction site. There will also be financial benefits. We expect to have about five percent compared to the construction of a conventional pumping station.”
At Desmi, Helena Edström is pleased with the collaboration with Priess District Heating because they have been able to deliver a unique solution that is not otherwise available on the Swedish market.
– “With the plug-and-play pumping station concept, we can deliver a unique solution at a fixed price and on time”, says Helena Edström and continues
– “There is huge potential for this kind of solution in Sweden.”
– “The FELIX project, where surplus heat from Gävle is converted into district heating for the benefit of consumers in Sandviken, is one of the best things I’ve been involved in. It really shows what we can achieve with our plug-and-play concept. It’s modular and similar to building blocks that can be put together in flexible solutions. And since it’s plug-and-play, we can deliver it anywhere in the world”, concludes Jacob Holdgaard, Priess District Heating A/S.
