Determination of optimal dimensions of fixed shadowing systems (pergolas) to reduce energy consumption in buildings in Romania

Depending on the season, the sun light entering a building has a varying impact upon the energy consumption of the building. Thus, during winter, the sunlight reaching the façade of a south-oriented building can provide passive solar heating, hence reducing the energy consumption required to heat the building. Contrary to this, during summer, the sun rays penetrating the building mainly through windows oriented towards the south lead to excessive accumulation of heat. To diminish the thermal lack of comfort, it is necessary to increase energy consumption required to cool the building. The fixed shadowing devices such as pergolas, when well designed, are able to significantly reduce the energy consumption required to cool the building during summer and also to allow for the energy contribution from the solar beams, during winter. Shadowing has always been recommended as a passive way to diminish solar heat input in constructions. In order to reach this aim, i.e. of reducing energy consumption in buildings in Romania, the present paper presents the optimal dimensions of fixed shadowing devices, namely of pergolas.