Increasing Coverage of Heating Demand by PVs Electricity Generation through Geometrical Modification in a Medium Sized Building
Creators: name: Rahmani, A.
name: Wagner, R.
Publisher: name: WIP
Year: 2019
Subjects: PV Applications and Integration
PV on/in Buildings, Infrastructure, Landscape, Water and Nature

description: 36th European Photovoltaic Solar Energy Conference and Exhibition; 1847-1856
description: In residential buildings integrating PVs to compensate energy demand, energy performance of each individual building is geometrically influenced by its own proportional/directional dimensions that can partly change light absorption or project shading in different intervals. To reach to an acceptable level of energy performance of a building, it is essential that geometry of building can purposefully fulfill to reach to these targets; a- Adequate potential of geometry to integrate passive strategies to minimize “heating demand” as well as “cooling demand” (even if cooling period is short) [10]. In this case, “Passive house criteria, defines the energy performance standard that building has to meet. Main subdivisions of this criteria influenced by building’s geometry are; “space heating demand”, “space cooling demand” and “primary energy demand” [12]. b- Geometrical sufficiency of areas for solar panels integration. (In this work, as energy demand will be mainly compensated by photovoltaics, so PVs will be considered as “solar panels”.) These areas can belong to any component of building. This sufficiency is a sequent of desired energy balance that could mainly be parametric with regard to parallel mechanical devices integrated in each building [11]. So far, in majority of ZEBs mounting PVs (as roof mounting or BIPV integrated on any component), the main target was generating the most possible annual electricity, considering energy payback time (ETBT) and the first financial investing [13]. Till now, following this scenario has resulted ZEBs that although their annual electricity generation compensates their energy demand, but during peak demands of heating that building needs more energy, they need to buy electricity and during summer times, mainly they are electricity sellers [1]. From economical point of view, the reason was a remarkable higher price of feeding surplus of electricity into the grid compared to price of generation of electricity. By moderating “feed-in tariffs” in Germany, the old scenario of generating the maximum electricity during the months with the highest irradiation (mainly in summer), has to veer to generating more electricity in intervals with the most demand, even if the total annual generation is relatively less [2]. The very first advantages of this tendency for individual owners will be less dependence on grid offering minimising annual electricity bills, moderating capacity of batteries and invertors and decreasing relative maintenance costs [3]. So, despite of majority of definitions of ZEBs that only argue for compensating annual electricity by building, a more accurate definition could be sufficiency of building to cover its own energy demand exactly during peak periods [4]. With regard to climate of Germany, main constant energy demand of buildings is heating, so a higher comparative electricity generation in winter times has been focused as the main scope of this work, although the cooling demand of simulated prototypes have been also taken into the account.