Torshavn Swimming Pool

Warm wastewater used to heat domestic water

With 165,000 visitors every year, the swimming pool in Torshavn is the largest on the Faroe Islands. In 2013, the annual energy consumption for heating shower water was 327 MWh. By installing four DE-5 heat exchangers from Defined Energy, this was reduced by 58% to 139 MWh per year.


Every year, 3000 TWh are used in Europe for heating water, which is then flushed out as wastewater. In 2013, before the solution from Defined Energy was installed at Torshavn swimming pool, used hot water was flushed out as wastewater, and 327 MWh were used every year to heat domestic water for shower water.

Solution and Results

The heat exchangers developed by Defined Energy make it possible to recycle the energy stored in the warm wastewater by letting it heat domestic water. Defined Energy examined what the most suitable solution would be for reducing energy consumption at Torshavn swimming pool. According to the analysis, four DE-5 heat exchangers from Defined Energy are sufficient to recycle energy from the warm wastewater, so they were installed. The result was a 58% reduction in energy used to heat domestic water in the swimming pool, or 139MWh saved per year.

Defined Energy offers two types of solutions; A customer can either buy DE-5 heat exchangers with service or they can be rented. Torshavn swimming pool chose to rent the DE-5s for a 10 year period, thereby reducing the cost of heating water from day one. After the 10 year renting period, the four DE-5 heat exchangers belong to Torshavn swimming pool. The lifespan of the DE-5 is estimated to be 30 years. The DE-5 heat exchangers can also be purchased instead of rented. The payback period differs slightly from project to project, but is typically 4-5 years.

Installation diagram

Torshavn DE-5 Installation
Warm water from the showers passes through the heat exchanger, which feeds the reclaimed heat into the boiler.


Torshavn Swimming Pool
With 4 pools, the facility is the largest in the Faroe Islands.


The DE-5 Heat Exchangers
Taking up only a few square meters of space, the heat exchangers are placed in a ventilation duct below the shower rooms.