In the Utrecht Science Park, Utrecht University uses thermal storage (in Dutch: warmte- en koudeopslag, wko). In thermal storage, warmth and cold released by the buildings is stored in the ground, so it can be used for heating or cooling at a later time.

This animation (Dutch) shows how the thermal storage system works.


UU has realised two thermal storage systems in the south-east and north-west corners of Utrecht Science Park De Uithof. In the south-east corner of USP De Uithof, the area between the M├╝nsterlaan and Limalaan, it involves two heat sources and two cold sources. These sources are connected to each other by means of a ring system. Two rings (cold and warmth) have been realised for this ring net.

Anton Pijpers opent wko systeem Diergeneeskunde
Opening of one of the thermal-storage sources.

The sources have been placed at a depth between 16 (filtration height) and 50 metres and are connected directly to the ring. Users can draw warmth and cold from the rings at the same time, but they can also exchange them. This way, the warmth that laboratories create can be used to heat other buildings.

The nett difference, like how there is more demand for warmth in winter, will first be provided by the thermal sources. After that, the heating net pitches in if needed. The ring system can easily be expanded if more buildings are connected to the thermal storage system.

A ring system with sources has also been realised in the north-west corner of USP De Uithof, the area between the Princetonlaan and Leuvenlaan. In total, this involves twelve sources (six warm and six cold), two kilometres of pipes and eight independently operating distribution systems in various buildings.


The annual conservation on primary energy use is 770,000 m3 of natural gas. This comes down to 14,500 GJ/year, which results in an energy conservation of approximately 3 % for the entire Uithof. If you compare the conserved use with the energy use of just the north-west cluster, this even results in a conservation of approximately 17 %. This reduces the CO2 emission with 1,020 tonnes per year.


The buildings of student housing corporation SSH (Johanna, Cambridgelaan, Bisschoppen and Casa Confetti) are connected to the warmth net of UU. Because of this, the residual warmth of the energy plant can be used for heating and hot tap water.