Results of the latest research about thermal use of solar energy in multi-storey housing, prepared for builders and planners

The relevant Know-How in the fields of "sustainable building and energy supply" will be gathered. The information will be transferred to the relevant target groups (building promoters, architects, planners, customers). This will be done during workshops, planning assistance and a catalogue of quality criteria. The focus lies on solar thermal systems for multiple-family houses.

Content Description




It is impossible to imagine modern living within the Austrian and European energy supply without the technology of solar thermal collectors. In the last four years the areas in which collectors have been installed in Austria have increased in total about 70 %.

Alone in 2007, collector areas of 281,000 m² (197 MWth) have been installed in Austria, which in relation to the number of inhabitants means that worldwide Austria was only beaten by Cy-prus and Israel which have enormous climatic. In addition, the strong home market also supports the position of Austrian companies in the international market, because of the 2.7 million m² collector areas (1.9 GWth) installed, 39 % originate from home-produced products. All in all by the end of 2007, 3.6 million m² collector areas or 2.5 GWth have been installed in Austria.

Nevertheless, the main part of the solar plants (90 % of the collector areas installed) is utilized by detached and semi-detached houses. Although the potential for multi-family houses would be enormous, by the end of 2007 the market penetration was only about 3 %. However, there can be seen an increased realisation in this segment because between 2003 and 2007 - the market penetration has tripled, for the reason, that based on relevant research works, solar heat could be established as a standard supply in new multi-family buildings.

On the one hand, the representational project "WohnSolar" forced the market penetration and on the other hand the project increased the quality of solar supported heating systems for multi-family houses. In this way the predetermined objectives were completely reached.

Within the project "WohnSolar" the actors (developers, planners, installers, architects, energy service providers etc) could learn the up to date knowledge based on a quality criteria catalogue and a planning guide which were both developed within the project. Especially the planning guide, which contains more than 50 pages offers a compact reference book for the subjects of planning, installation and operational management.

Thus, planner-workshops in the cities of St. Pölten, Salzburg, Eisenstadt, Dornbirn and Klagenfurt were held. The interest for the events was enormous and hence 331 participants at-tended the five workshops, which means an average of 66 participants per event.

Also, parallel to the workshops for the planners, contacts to the developers were intensified. The aim was to establish one "model-developer" per province. While in some of the provinces in Austria, already-existing contacts could be built up, in others, new multipliers had to be found. But finally, ten "model-developers" - of which one in each province and two in Styria - could be established. Each "model-developer" is based on specific services concerning the use of solar heat (self commitment, model demonstration projects, future perspectives etc.).For details of the model-developers please see:

The enquiries of international research results as well as the analyses of the most important European solar markets have shown that Austria is the technological leader in this field. Thus, the Austrian solar industry provides large potential. Nevertheless, the technology analyses within the project "WohnSolar" have clearly pointed out: It is possible to implement a high-quality and economically reasonable solar plant for multi-family houses when current standards of planning, installation and operational management were complied with (look at the planning guide) and it should be claimed that this standards are rated as assumptions for the residential building subsidies. If the heat supply of new built as well as existing multi-family houses should be provided by solar systems further research- and technology development is necessary (tank systems with higher energy-density, solar panel as multifunctional building component, new materials for decreasing costs ,…). Besides that the existing law in Austria (law of tenancy and law of residential property) should be adapted.

Project Partners

Project management

Ing. Christian Fink, DI Thomas Müller

Project or cooperation partner


Dipl. Ing. Thomas Müller
Feldgasse 19, 8200 Gleisdorf
Tel.: +43 (3112) 5886-16
Fax +43 (3112) 5886-18