Vridsløsemagle – Thermonet

Overview of the pipeline network and boreholes in Vridsløsemagle

Vridsløsemagle – Thermonet

The project involves converting oil-heated homes in the village of Vridsløsemagle to a thermonet system – also referred to as “low-temperature district heating” or “cold district heating.”

The thermonet in Vridsløsemagle utilizes ground-source energy via a combination of approx. 200-meter-deep vertical boreholes and horizontal distribution pipelines supplying each connected household. The system is designed to feed individual water-to-water heat pumps installed in each home. This approach ensures efficient and sustainable heating with significant CO₂ reductions compared to the reference scenario based on oil heating.

The project period spanned from November 2021, when the project proposal phase began, to 1 May 2024, when the final section was commissioned.

Norsyn’s Contributions to the Project

Høje Taastrup District Heating initiated a feasibility study for establishing cold district heating in Vridsløsemagle – a so-called “oil village” with 110 dwellings located in Høje Taastrup Municipality. This innovative initiative aimed to convert homes from oil heating to a more efficient and sustainable thermonet solution.

Norsyn introduced the thermonet/cold district heating concept and conducted financial assessments both at utility and end-user level to ensure overall economic viability and sustainability.

In addition to the financial analyses, we prepared a comprehensive project proposal including socioeconomic evaluations.

Following approval of the project, Norsyn carried out the system design and detailed engineering as well as the tender process.

Pressure profile from hydraulic Leanheat model – the analysis identifies pressure-related issues that have since been resolved
P&ID diagram of the pumping station

System dimensioning included hydraulic design using a Danfoss Leanheat-based model. Since the heat pumps operate within a pressure range of 1–3 bar, hydraulic stability is critical to system performance and design.

We also dimensioned the thermonet in terms of thermal output and energy uptake to ensure sufficient capacity on the coldest days of the year and adequate energy delivery across the full annual load profile.

The project demonstrates a successful transition from oil heating to an innovative thermonet system, highlighting the potential of collective heating even in small rural villages where traditional district heating is not financially feasible and individual solutions are typically the only alternative.