Print Email Facebook Twitter A photovoltaic window with sun-tracking shading elements towards maximum power generation and non-glare daylighting Title A photovoltaic window with sun-tracking shading elements towards maximum power generation and non-glare daylighting Author Gao, Y. (TU Delft Photovoltaic Materials and Devices; Nanjing University; Changzhou Institute of Technology Research for Solid State Lighting) Dong, J. (Chinese Academy of Sciences) Isabella, O. (TU Delft Photovoltaic Materials and Devices) Santbergen, R. (TU Delft Photovoltaic Materials and Devices) Tan, H. (Nanjing University) Zeman, M. (TU Delft Electrical Sustainable Energy) Zhang, Kouchi (TU Delft Electronic Components, Technology and Materials) Department Electrical Sustainable Energy Date 2018 Abstract Vertical space bears great potential of solar energy especially for congested urban areas, where photovoltaic (PV) windows in high-rise buildings can contribute to both power generation and daylight harvest. Previous studies on sun-tracking PV windows strayed into the trade-off between tracking performance and mutual shading, failing to achieve the maximum energy generation. Here we first build integrated models which couple the performance of sun-tracking PV windows to the rotation angles. Secondly, one-degree-of-freedom (DOF) and two-DOF sun tracking are mathematically proven to be not able to gain either maximum power generation or non-glare daylighting under reasonable assumptions. Then we derive the optimum rotation angles of the variable-pivot-three-degree-of-freedom (VP-3-DOF) sun-tracking elements and demonstrate that the optimum VP-3-DOF sun tracking can achieve the aforementioned goals. When the restriction of the proposed model is relaxed, the same performance can be achieved by the optimum one-DOF sun tracking with extended PV slats and particular design of cell layout, requiring less complicated mechanical structures. Simulation results of nine global cities show that the annual energy generation and average module efficiency are improved respectively by 27.40% and 19.17% via the optimum VP-3-DOF sun tracking over the conventional perpendicular sun tracking. The proposed optimum sun-tracking methods also reveal better protection against sun glare. The optimum VP-3-DOF sun tracking is also demonstrated to be applicable to horizontal PV windows, as those applied in the sun roof of a glass greenhouse. Subject photovoltaicspartial shading effectssun-tracking methodsBIPVsolar energy To reference this document use: http://resolver.tudelft.nl/uuid:0ea3ea0d-5da1-4a09-8ee8-73dc3cdff54d DOI https://doi.org/10.1016/j.apenergy.2018.07.015 ISSN 0306-2619 Source Applied Energy, 228, 1454-1472 Part of collection Institutional Repository Document type journal article Rights © 2018 Y. Gao, J. Dong, O. Isabella, R. Santbergen, H. Tan, M. Zeman, Kouchi Zhang Files PDF 45784725_Manuscript_SunTr ... 180310.pdf 5.03 MB Close viewer /islandora/object/uuid:0ea3ea0d-5da1-4a09-8ee8-73dc3cdff54d/datastream/OBJ/view