At Norrtåg's facility in Umeå, Northern Sweden, large amounts of hot water are used to ice off the trains. The project team saw the opportunity to recycle the heat in the waste water to raise the temperature of incoming cold water and thus save large amounts of energy. Installation includes tanks, pump pits and control cabinets. Commissioning and final inspection was carried out in October 2017, the plant has since been in operation without the need for maintenance or cleaning.
Recycling increases the temperature of incoming cold water by switching outbound waste water using Evertherm collectors. After the rise in temperature, the water is regulated to the correct temperature with the help of district heating. The plant is designed to deliver about 180 kW at a waste water temperature of 25 degrees.