Not only Denmark, the forerunner in the field of solar district heating, makes progress. In Denkmark there are more than 100 cities and communities with solar district heating plants – mostly with shares of 15 to 60 per cent of the local district heating supply. However, other countries like Austria, Germany, France and Sweden catch up. The well-proven solar district heating technology is being more and more applied in these countries – with a broad variety of scale: There are installations which supply solar thermal heat for urban quarters, there are so called bioenergy villages where solar thermal plants supply the entire heating demand in summer time, and there are huge plants built on fields with up to 100 megawatt thermal capacity as in the Danish city Silkeborg.
Compared to the previous conference in Billund, Denmark, which took place in 2016, the number of participants is twice as high this year. The 350 participants come from 33 countries. The conference managers, Christian Fink from AEE Institute for Sustainable Energy (AEE INTEC) in Graz and Thomas Pauschinger from the Steinbeis Research Institute Solites in Stuttgart, Germany, judge this a very positive signal for the use of solar thermal in local and district heating networks. Pauschinger emphasized that the EU commission reliably supports this kind of international cooperation for the further development of solar district heating. ‘We have been able to successfully develop this conference also due to the support of the EU commission, starting in 2009 and lasting until today.’ Fink said: ‘It is the goal of the conference to bring together business experts and decision makers who are interested in using the technology and to make use of this impulse for new projects.’
Two excursions on Wednesday afternoon to solar district heating plants in the Graz area were an appreciated opportunity for networking and discussions. It is not by accident that Graz was chosen for the conference this year. The second biggest city in Austria plans to completely decarbonize its district heating network. For a CO2-neutral supply a project called ‘Big Solar’ is in preparation. 450 000 square meters solar collectors shall be installed. Christian Purrer, board speaker of Energie Steiermark emphasized at the conference: ‘It is our goal to significantly increase the share of renewable energy in the heat supply in the coming years in order to combine security of supply with even more sustainability. Solar thermal in combination with big thermal storage tanks, as in our project Big Solar, play a leading role in it.’
Fotos: Energie Graz (HELIOS Anlage), Guido Bröer (Fernheizwerk Puchstrasse Anlage)