Energetic Sustainability Assessment about Passive Solar Systems by a Finite Differences Code

The use of bioclimatic solutions in architecture has been for a long time in Europe aconsolidated procedure, especially developed in northern countries. In the last years, in Italytoo, It has been followed through a good policy to increase the construction of buildingsequipped with solar energy harnessing system; many architectural competitions expressly askfor passive solar architectonic solutions. In this study, It has been assessed the energeticperformance of a solar passive building by a finite differences code (TRNSYS).Many tests and simulations have been carried out on a residential building, changing theconfigurations of the building envelope and transparent or opaque surfaces.It has been calculated the thermal performance of a south-facing building, in which thefaade, chancing configuration, is made up of opaque wall and windows, or a completelytransparent surface, testing many kind of glasses (direct gain sunspace) or small sunspacesagainst a thermal storage matt wall.Thanks to these final results, It has been possible to make some considerations about differentkinds of proposed passive solar solutions, picking out the more convenient ones as to theirenergy performances and appropriate lighting and thermal indoor comfort.This work would arise a contribution about: a correct way of bioclimatic design, by using transparent insulating materials, new kinds of direct gain sunspaces, that allow energy saving of 50%, sustainable energy use of building envelope.