River water can heat a city, prize-winning thesis suggests


Students’ model shows that heat from the river Dijle could replace all of Leuven’s domestic gas heating

Heat flows

Two engineers studying at KU Leuven have won this year’s Scriptie prize, for a master’s thesis that investigates how river water could be used to heat a city’s homes. Sebastian Baes and Jan Denayer worked out that it would be possible to replace all of the domestic gas heating in Leuven by drawing warmth from the river Dijle as it flows through the city.

The whole world is looking for green sources of energy, and when it comes to heat one of the most promising ideas is to extract it from the natural environment. Geothermal energy, for example, takes heat stored in the ground and uses it to warm up buildings.

But heat is also stored in water on the surface, so Baes and Denayer (pictured above) set out to calculate how much heat they could theoretically take from the Dijle as it flows through Leuven. The challenge they faced was to take enough heat to be useful, but not so much that the temperature of the river dropped too far and damaged the plants and animals living in it.

Their mathematical models demonstrate that it would be possible to replace all of the domestic gas heating in Leuven with heat from the Dijle, without causing a drop of more than 1.66 degrees centigrade in the middle of winter. Since the maximum permitted drop was considered to be 3.0 degrees, it would also be possible for downstream settlements such as Mechelen to take heat from the river as well.

Clear winners

The €2,500 Scriptie prize recognises not only the scientific value of the research in the winning thesis, but also its news value and how the researchers communicated their work to a non-expert audience. Baes and Denayer convinced the jury with the originality of their idea and the power of their maths, as well as the clarity of their pitch.

“The work is very clearly structured, so that policymakers who are not familiar with the technical details can also get to work on this research,” the jury said. “If all technical studies were written this clearly, much more research would be picked up and used.”

More than 500 theses were submitted for the competition. The Agoria Prize for best technological thesis went to Nadia Wiesé and Davy Didden from KU Leuven, for their work on smart batteries. Babette Lamote of Ghent University won the EOS Prize for her work making biofuel from agricultural waste.

Lien De Saegher of KU Leuven won the Klasse Prize with a master’s thesis on space education in primary school. And the bachelor’s prize went to Elias Callewaert of Artevelde University of Applied Sciences in Ghent, for his undergraduate thesis on drama therapy in quarantine.

Photo: KU Leuven master’s students Sebastian Baes (left) and Jan Denayer  
© Kevin Faingnaert