Development of solar ventilated façade system for building energy retrofit

In the perspective of setting ambitious targets for new buildings energy performance and of introducing new approaches to retrofit existing buildings, the implementation of solar thermal collectors into façade becomes very interesting Several research activities are currently pursued to facilitate the architectural integration of collectors in the building skin, , mainly in the glazed flat plate collectors’ domain. This paper presents a new approach for unglazed flat plate collectors,. The idea is to develop a new collector conceived from scratch as a building element, either façade metallic cladding or roof covering. The base element is an absorber whose hydraulic circuit is made using the “roll bond” technique. The building element chosen can then be formed by bending a non active band left around the absorber area in the roll bond process. Insulation can finally be added on the back of the module or in the mounting process. Selectivity and colours can be obtained spraying TISS (Thickness Insensitive Spectrally Selective) paints, or using vacuum deposition. Simulations have been carried out to better analyse possible applications on different buildings and drive the prototype realisation. The whole project arises from a constructive cooperation between research institutes and industry of solar collectors and façade systems.