The Faroese company “Defined Energy” has pioneered a new way of using energy as it developed a solution to recirculate warm wastewater to heat domestic water. The solution has been installed first in the swimming pool in the capital Tórshavn in 2014 and showed good results.

According to “Defined Energy”, 3000 TWh are used each year throughout Europe to heat water which is flushed out as wastewater. The heat exchangers make it possible to recirculate and extract the energy from the wastewater to heat domestic water. Thereby reducing energy consumption and thus reducing CO2 emissions.

The heat exchangers have reduced the energy consumption for heating water with 58 % from 327 MWh to 139 MWh per year by recycling the energy from showers’ wastewater to heat up the domestic water again.

“Defined Energy” and their system to use the heat from wastewater has been presented as a best practice example in the EU project SECURE (Smarter Energy Communities in Northern & Arctic Regions) funded by the “Northern Periphery” and “Arctic Program 2014-2020”.

Another good example of heating exchangers can be also found in Tórshavn, a 64-apartment retirement home Boðanesheimið, that is heated by water-to-air heat exchangers. Four heat pumps on 60 kW each extract heat from the Gulf Stream by cooling the water with two degrees. The produced energy is used to heat the rooms as well as the water in the retirement home. The system was installed and put into use in 2012.

Keywords: wastewater, heating, heat exchangers, energy efficiency, Tórshavn, Faroe Islands