Heating consumption less than expected

Haukiniemen Hidalgo is the first apartment building in Iisalmi, Finland to utilise geothermal heating and geocooling. The geothermal system has now been operating for well over 2.5 years and the heating consumption is a positive surprise to the residents. In 2015 the heating consumption was 33,000 kWh and the expected consumption for 2016 is 36,000 kWh. That is one-fifth less than it was anticipated after the first eight operating months; at that time, the annual consumption was estimated to average 45 MWh.

“Taking into account the size and shape of the building, it can be said that we — Gebwell Ltd. and Rakennusliike Pentikäinen (the manufacturer) — have succeeded in the choice of the system and have managed to get the system to work as energy efficiently as possible,” Tuomo Pentikäinen summarised while disclosing the consumption figures in 2016.

The five-storey building with a floorspace of 1246 m², a total area of 2038 m² and volume of 6150 m³, is heated with two 30 kW Gebwell T heat pumps taking heat from eight energy wells. The system also has a 2 m³ accumulator for heating and a 1 m³ accumulator for domestic hot water production. The domestic hot water is preheated by two heating coils in the heating accumulator and is then directed to a DHW exchanger.

Special attention was paid to the sound level of the system. All the premises have underfloor heating, which is controlled by room thermostats in all rooms except shower rooms. The circulation pumps in all heating networks are the most energy-efficient models available.

The geothermal system is equipped with a telemonitoring device, with which the running modes, temperature of incoming and outgoing liquid solutions, accumulator temperatures, etc. can be monitored. Gebwell as the heat pump supplier can monitor the operation of the system and make adjustments to settings via remote access.

Gebwell geothermal system
8 pc 200 metre energy wells
60 kW ground source heat pump
2000 litre heating accumulator and 1000 litre domestic hot water accumulator

Property and consumption details
Floorspace 1246 m²
Volume 6150 m³
Heating consumption 2015: 33,000 kWh
Heat consumption in 2016: 36,000 kWh