Modeling and analysis of Building Attached Photovoltaic Integrated Shading Systems (BAPVIS) aiming for zero energy buildings in hot regions

Photovoltaic systems are recently attached to existing building envelopes referred to as Building attached Photovoltaics. They act as multifunctional elements that generate electricity and also provide shading to the building and are referred to as Photovoltaic integrated (PVIS) systems. They can decrease the indoor thermal gain and lighting requirements and act as a power generator to reach zero energy buildings. Thus, there was a need studying the effect of PVIS systems on the energy generated and on the internal heat gain and lighting requirements in Egypt. In this study, four experimental models are manufactured out of the most thermally-conductive building materials where each model has a PVIS attached on its window. The experiments are carried out in summer 2017 in Egypt. Data is analyzed using Minitab® 17 to find predictive models of power generation, indoor illumination and indoor temperature which is a novel concept to be adopted, according to the pool of existing knowledge. Results showed promising predictive models with high R-Sq values. Later, the predictive models are optimized using particle swarm optimization to find the optimal tilt angle of PVIS that maximizes the power generation, indoor illumination and minimize the indoor temperature to reach Zero energy buildings. The optimal tilt angles for PVIS systems were in the range of 64° to 70° in Egypt.