Within the scope of its stimulation program "Sustainable Economy" the Austrian Federal Ministry of Transport, Innovation and Technology (BMVIT) dedicated its sub-program "Building of Tomorrow" to a particularly important issue: future-oriented dwelling and building construction. Sustainable residential and office buildings can be defined as buildings offering a high level of quality of life and user-oriented features and taking into account ecological aspects and which, at the same time, are highly cost-efficient as to construction and operation. The five year research program "Building of Tomorrow" aims at developing sustainable solutions for residential, office, and commercial buildings with a high market potential. The program is to support innovative research, development, and demonstration projects and to demonstrate the feasibility of various technologies by means of concrete projects.
One of the focal points in the category "technology development" consisted in the elaboration of scientific fundamentals and the development of solar collectors. The following projects have been selected:
Utilization of solar energy by means of thermal collectors meets with growing interest in Austria. These usually small-scale installations are used predominantly for hot water supply. Other applications such as solar space heating, large-scale installations in urban residential buildings or solar-based district heating meet with problems as there is not enough roof area with adequate tilt angle and orientation towards the sun. When mounted on existing roofs either directly or by means of supports these installations often have the effect of an alien element.
With a view to a broader market introduction it is therefore necessary to develop sophisticated solutions for the integration of collectors in the envelope of a building. Apart from technical-functional aspects, other factors such as an esthetic design and improved integration into the roof or the facade play an important role in this context. The integration in the facade [>>INFO], in particular, offers promising marketing opportunities, which have not been covered by conventional roof-integrated or roof-mounted systems.
The companies AEE INTEC, GREENoneTEC, and DOMA Solartechnik concentrated on the following items:
The goal consists in developing constructive solutions for the abovementioned items and to provide manufacturers, planners, and architects with the basic knowledge and a database necessary for the sizing, manufacture, and installation of facade-integrated solar collectors. The participants of this project have succeeded in establishing a close cooperation between research and industry thus promoting the process of implementation.
The facade-integrated collector serves not only as collector, it also serves as thermal insulation and as a formal element of the facade. This multi-purpose use of building components may result in a reduction of costs. Another advantage of facade-integrated collectors consists in a rather even irradiation of sunlight over the whole year. The fact that inclined collectors can be snow covered in winter, while facade-integrated collectors benefit from increased irradiation through reflection from snow has been largely neglected until recently
