Ground Source Heat Pump with Borehole Thermal Energy Storage at the Headquarters of INFRAX

Project information

Index: 0992C3
Priority:2: Environment and risk prevention
Sub Theme:Energy and sustainable transport
Location BELGIQUE-BELGIË VLAAMS GEWEST TORHOUT Prov. West-Vlaanderen Start/End date of the practice
Start: 2009-12-01
End: ongoing

Topic of the practice

Combination of several eco-innovative technologies including ground source heat pumps (GSHP)

Good Practice Information

This project comprises an active double skin with integrated photo-voltaic elements, slab heating and cooling and a ground coupled heat pump of 160 kW combined with a BTES (Borehole Thermal Energy Storage) system (24 vertical heat exchangers with depth of 130m). It provides an optimal example of Trias Energetica. At first, building skin is constructed in order to avoid heating in winter and cooling in summer, secondly the remaining energy demand is covered by a very efficient renewable energy system and at last the energy peak is covered in a traditional way. The expected coverage of energy demand is: 68% of heat demand covered by Heat Pumps (HP); 52% of cooling demand with BTES in free cooling mode; 91% of cooling demand with BTES + HP as chiller. The cost-benefit analysis estimates: Investment HP+BTES = 123,000 € (extra investment = 69,000 €); Reduction exploitation cost ≈ 7,000 €; Simple payback ≈ 10 years. The total actual cost on 30 years decreases from €758,000 (conventional) to €603,000 (GSHP) - a profit of 20% on the lifetime cost of the energy system

Evidence of success

The practice is a demonstration project for INFRAX, implemented in their own office building, which shows the excellent possibilities of combining a nice office building with high comfort requirements together with a sustainable energy system. The installation reduces primary energy use with 37% with a yearly saving of 174 MWh, this results in the emission reduction of greenhouse gas with 33 tons a year (-32%).The project won several prices in Belgium and abroad (Challenge 2020, Green Good Design Award). The project demonstrates the importance of green heating and cooling by means of a ground coupled heat pump system. Together with the installed green power installation on PV the installation shows that aiming for zero energy or even net positive energy buildings are perfectly possible.

Contact details to obtain further information on the practice

Hans Hoes

Terra Energy nv

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