advanced building skins 14 | 15 June 2012 - lamp.tugraz.at - Graz ...

Advanced Building Skins
facade. The effort required to clean the glass facade is not increased by the protective glazing does nor
are there additional security requirements in case of damage. The two different installation scenarios
meet different needs and requirements from the market and therefore could even work symbiotically.
As part of the research project, the technical grade of the facade collector (vacuum tube outside and
behind glass) was further developed and improved towards small series. Due to the departure of the
Schott Glass Tube company, a new vacuum tube type, the Paradigm Sydney-tube, and the review of
the program in terms of the new vacuum tube type is necessary. Important aspects in this regard were,
in addition to energy, cleaning and security in the event of damage, the function of the collector as a
facade for sun protection and daylighting in office buildings.
3 Thermal measurements and simulations
Both installation scenarios have been assessed based on functional prototypes.
The baseline measurements for the thermal efficiency of the collector were carried out by the Institute
for Thermodynamics and Thermal Engineering (ITW), University of Stuttgart.
Figure 2: Measures of the façade collector system at the ITW of the University of Stuttgart
The simulation calculations performed on the basis of these measurements by the Solites Research
Institute for Solar and Sustainable Thermal Energy Systems at the Steinbeis Foundation produced
encouraging results.
For the load case "office" at the Freiburg site, the proportion of demand met by solar energy was 40%
for heating and 30% for cooling. In essence, the research project simulations showed that the support
of the architectural development in particular is essential. This is due to the fact that the solar thermal
yield of possible systems depends strongly on the geometrical arrangement of the vacuum tubes and
the design details. Moreover, while generally speaking the yields achievable in a vertical facades
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