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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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Building-integrated photo-voltaics: market challenges and bioinspired solutions
We have heavily relied for a few centuries on fossil fuels, which are basically dead plant material that was sequestered and converted millions of years ago, but the rapidly increasing energy demand combined with climatic challenges means we need to develop a large-scale supply of energy from sources without climatic impact. An obvious choice is to use solar energy directly when possible, and a complete global transition to solar energy by 2050 is realistic and cost effective. However, in order to find space for the large areas needed for harvesting solar energy by photovoltaic means, it would be advantageous if solar panels could be incorporated into urban buildings and free land for other uses. We undertook an analysis of the needs and requirements from the building industry that will allow for a more widespread use of solar panels on buildings, also referred to as Building Integrated Photo-Voltaics. Specifications and options for the visual incorporation of the solar panels in the building envelope were identified. Special attention was paid to (i) the role of modularization and standardization in architecture and (ii) the role of color and reflectance. A standardized mounting system is proposed that will allow for modular attachment of solar panels, making it easy to adjust, repair, and replace individual panels. Biological inspiration can be used to improve the system further. The forced-air ventilation of the tunnels of prairie dogs shows how to enhance cooling. The non-iridescent wings of butterflies of the Morpho genus, proposes how a low-cost structurally colored film can be inserted into the solar panel during its assembly.
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- PAR ID:
- 10273643
- Editor(s):
- Lakhtakia, Akhlesh; Martín-Palma, Raúl J.; Knez, Mato
- Date Published:
- Journal Name:
- SPIE Proceedings Volume 11586, Bioinspiration, Biomimetics, and Bioreplication XI
- Page Range / eLocation ID:
- 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2583504
