In Denmark, the objectives for future energy supply are clear. Renewable and fossil free energy sources shall purely substitute oil and gas. With an existing district heating network in all towns and cities there is high focus on new ways for centrally production. District heating is independent to energy source, why several kinds of energy often are used in one and same town.

Solar heating has become more and more common and typically it can cover up to 20% of the heat demand. When installed the only costs are for operation and maintenance, whereas the energy from the sun is for free. That means a known and stable price for the consumer.

This summer a new solar plant has been established in the town Aabybro. A town in Northern part of Jutland with 6.000 inhabitants. Since 2016 the main source for district heating has been wood chips and in future it will be supplemented by solar heat from the new 22.000 m2 solar plant. Solar panels are delivered by Arcon Sunmark and the pipe system is from LOGSTOR.    

The challenge
Energy from the sun is for free; but it you cannot regulate the in-flow of energy and thereby the production of heat fluctuates within hours. This means frequent increases and decreases in temperature and following that very different stress levels in the pipe system. This has to be considered in design of the pipe network, which transport the hot water from the solar panels and out in the distribution network, and finally to the consumer.

The technology
Design of the network has to take the changes in temperature and stress levels into account. It shall be made in a way that at the same time allows and absorbs the stresses and thereby avoid any possible breakdown of the pipe system. The lifetime of a pipe system is minimum 30 years and the right design is a pre-assumption for this.

Following this detailed design the measurements of each single component in the pipe system needs to be exact and shall be installed strictly according to drawing. That means production of customized components in form of pipes, different types of pre-fabricated bends and t-pieces, and valves. Standard joints and surveillance system are also part of the delivery.

Every component is individually labelled and the labelling can be read on the drawings for LOGSTOR pipe system as well as on the drawings for the surveillance system. All together it is a kind of building kit, which once on the job-site is easy to understand, handle and install.

LOGSTOR values
Solar heating for district heating started in Denmark more than 20 years ago and from the very beginning LOGSTOR was involved in these projects with the project in Silkeborg – worlds largest solar heating plant – as the biggest reference.

Over the years we gained valuable experience in design. We know the very special conditions that the pipe system has to handle and bring this know-how into every new project. In this year we have already delivered the LOGSTOR pipe system to eight new solar plants. Not only in Denmark; but also abroad.

With development of the building kit concept, which was made in close co-operation with Arcon Sunmark we have now a complete package for the pipe system. This ensures an optimal system, which is easy to install and which will met the demand for flawless supply of district heating for decades.

Pictures below taken on a sunny day in June 2018, taken by Carsten Als, Project Execution Manager at LOGSTOR A/S

LOGSTOR customized components manufactured for easy assembly in the field.

ARCON-SUNMARK installed solar panels perfectly aligned row by row.


For specific information about design of pipe system for solar heating, follow this link: