Water treatment for solar heating system

SUNSTORE 4 is the name of the seasonal pit heat storage at Marstal's extended solar district heating network at the Danish island of Aeroe. The solar heating network uses a huge water reservoir of 75,000 m3 for storing thermal energy. 

Water supply for the establishment and filling of the 16 meters deep heat storage pit came directly from three nearby groundwater wells. To attain the water quality needed, the water was filtered by pressure filters followed by softening. 

A EUROWATER rental water treatment facility was used for this temporary assignment. Within the 70-day timeframe the heat storage pit was filled with water of the necessary, softened quality.  


Reference ID: 201208
Industry: District heating
Application: District heating water


Download PDF

Technical data

  • Hardness softened water: < 0.5 °dH

Units in plant

  • Pressure filter TF25
  • Pressure filter TF35
  • 3 x Softening plants type SFH 1802-F
  • Pumping station with 2 Grundfos pumps


See more references