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The rooftop is a default location for photovoltaic solar panels and is often not enough to offset increasing building energy consumption. The vertical surface of urban buildings offers a prime location to harness solar energy. The overall goal of this research is to evaluate power production potentials and multi-functionalities of a 3D building integrated photovoltaic (BIPV) facade system. The traditional BIPV which is laminated with window glass obscures the view-out and limits daylight penetration. Unlike the traditional system, the 3D solar module was configured to reflect the sun path geometry to maximize year-round solar exposure and energy production. In addition, the 3D BIPV façade offers multiple functionalities – solar regulations, daylighting penetration, and view-out, resulting in energy savings from heating, cooling, and artificial lighting load. Its ability to produce solar energy offsets building energy consumption and contributes to net-zero-energy buildings. Both solar simulations and physical prototyping were carried out to investigate the promises and challenges of the 3D BIPV façade system compared to a traditional BIPV system. With climate emergency on the rise and the need for clean, sustainable energy becoming ever more pressing, the 3D BIPV façade in this paper offers a creative approach to tackling the problems of power production, building energy savings, and user health and wellbeing.
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Circuit Connection Reconfiguration of Partially Shaded BIPV Systems, a Solution for Power Loss Reduction
Integrating PV panels as a source of clean energy has been a widely established method to achieve net-zero energy (NZE) buildings. The exterior envelope of the high-rise buildings can serve as the best place to integrate PV panels for utilizing solar energy. The taller the building, the higher the potential to utilize solar energy by PV panels. However, shadows casting on the BIPV façade systems are unavoidable as they are often subject to partial shades from panels self-shading as well as building walls. Partial shading or ununiform solar radiation on the PV surface causes a dramatic decrease in the current output of the circuit. For that reason, in BIPV facades the default circuit connection of manufactured PV panels does not output maximum power under partial shading conditions. This paper investigates the different circuit connections in BIPV façade system to achieve higher energy yields while addressing design requirements. To this end, PV power production in different circuit connection reconfiguration scenarios was explored in two levels of BIPV components: 1) PV cells, and 2) strings of PV cells. Experimental tests conducted to validate the simulation results. The results of this study indicated that the maximum power generation occurred when the circuit connection between cells within a string is series, and the circuit connection between the strings within a PV panel is parallel. Results of the experimental tests shown that the series-parallel circuit connection increases the energy yields of the BIPV facades 71 times in real-world applications. The comparison analysis of the Ladybug energy simulations and the proposed analysis Grasshopper analysis recipe power output showed that the developed Grasshopper script will increase the BIPVs energy yields by 90% in simulations.
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- Award ID(s):
- 2122014
- PAR ID:
- 10423404
- Date Published:
- Journal Name:
- ACSA Annual Meeting In Common
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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