抽象的

TILT AND ORIENTATION: A PREFERENCE FACTOR AMONG PHOTOVOLTAIC ROOF SYSTEMS

Ahmed A. Waseef

One of the most abundant renewable energy resources is solar energy. In the construction sector, buildings are the largest human fabric intercepting solar radiation; they are a driving sector for developing solar energy uses especially those for generating electricity; Photovoltaics (PV). PV can produce on-site electricity with no harmful emissions. Generally, PV modules (PVs) are placed as a lay-on or additive solution to the building external envelope. Initially, they were secured to the roof or onto a facade using a metal structure with the sole function of generating energy. Afterwards, PVs were thought of as buildings components "part of the building external envelope", thus becoming multifunctional construction materials bringing “added value” to building materials. Hence, the idea of integrating PVs in buildings arose and the Building Integrated Photovoltaic systems (BIPVs) concept was introduced. There are various typologies of BIPVs and vast number of factors/constraints affects the dual usage of PVs as electrical elements and architectural ones. There is a lack of consensus in the methodologies used for the BIPV implementation; there is a minority of tools connecting these factors in a way that enables stakeholders analysing BIPVs alternatives, thus choosing the most appropriate one. Hence, it is obvious that designing with BIPVs requires a much more holistic perspective than what has been typically applied for decision-making in the past. This approach focuses on the interaction between BIPVs basics/characteristics, and the constraints affecting their suitability for application. The paper will focus on one factor (tilt and orientation) and its effect on one BIPV typology (roof systems). At the end of this paper, a preference matrix will be conducted which resembles the interrelationship between PV roof systems and tilt and orientation factor. The aim of paper is to provide architects with an effective supporting tool to analyse different BIPV alternatives for any building within a specific location, to choose the most appropriate BIPV system.