The need to supply electricity to the building sector is growing worldwide. Currently, integrating photovoltaic (PV) panels into building rooftops is the primary method for harnessing solar energy. However, this practice, along with the use of solar farms, contributes to power grid fluctuation issues, known as the duck curve. Two main issues associated with the duck curve are PV power curtailment at midday and a sudden increase in utility operation during late afternoon hours. These problems are more significant in regions with higher PV power penetration into the grid, raising concerns that the current power grid infrastructure may not be able to accommodate the operation of conventional utilities alongside PV power generators.
Since the building sector is a major electricity consumer, supplying this sector's demand with an optimized PV system that not only meets building electricity needs and reduces energy consumption but also mitigates duck curve issues can significantly contribute to energy sustainability. This thesis investigates the impact of Building-Integrated Photovoltaic (BIPV) systems in mitigating power grid fluctuations through a comprehensive analysis. The findings of this study are presented in four research papers, each addressing a specific aspect of the main research objective. A brief summary of the findings is as follows:
Paper One: "Circuit Connection Reconfiguration of Partially Shaded BIPV Systems: A Solution for Power Loss Reduction" explores solutions to tackle power drops in BIPV façades due to partial shading conditions. The paper presents a novel circuit connection that significantly reduces power output reduction in BIPV façade systems.
Paper Two: "Comprehensive Analysis of Energy and Visual Performance of Building-Integrated Photovoltaics in All ASHRAE Climate Zones" examines various BIPV typologies, including PV-south louvers and PV-mounted roofs, in terms of building energy consumption, PV power output, and occupants' visual comfort. Results indicate that PV-south louvers significantly reduce building energy consumption in very hot, hot, and warm climates. In colder climates with significant heating demands, roof-mounted systems provide a better balance between power generation and solar heat gain. PV-south louvers effectively reduce glare on office working surfaces while providing the desired illuminance levels for occupants. However, PV-mounted roofs can cause excessive illuminance, leading to disturbing glare over large portions of the floor area.
Paper Three: "Assessing the PV-Integrated South Façade in Mitigating the BIPV System Oversupply" evaluates the effectiveness of PV-south louvers in reducing BIPV power curtailment at midday. The results show that these typologies effectively reduce power curtailment in very hot, hot, and warm climates, except in warm-marine sub-climate zone (3C). In mixed climates, the performance of these typologies varies across different months.
Paper Four: "Assessing the Impact of PV-Integrated West Façade in Alleviating the Duck Curve Steep Ramp in All ASHRAE Climate Zones" investigates the impact of PV-west fins on alleviating the duck curve's steep ramp in the late afternoon. The impact is limited in very hot and hot climates but shows more potential in warm, mixed, and cool climates. Cold, very cold, and Arctic climates exhibit higher effectiveness during warmer months.
This thesis provides a comprehensive analysis of the impact of BIPV systems in mitigating the duck curve issue. By optimizing BIPV configurations and understanding their performance across different climate zones, the findings of this thesis offer valuable insights into improving building energy and BIPV power production efficiency as well as addressing grid stability issues associated with the fast-growing integration of PV systems into the built environment.