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Windows are one of the main contributors to building energy consumption, and emerging dynamic window technologies offer improved performance. Specifically, NIRfocused window technologies are desirable in climates that consume both heating and cooling energy. However, the whole building energy effects of changeable NIR response of building windows have not been captured, largely due to the lack of an appropriate energy simulation method and NIR-focused window modeling. This study focuses on developing a simulation method that enables the comprehensive evaluation of the whole building energy effects of dynamic NIR modulations. Using an EnergyPlus EMS-based parametric framework, annual energy savings were estimated for a switchable between glass built-in system across three representative cities in ASHRAE climate zones 3, 4, and 5. This NIR-focused technology yielded energy savings of up to 19%. The results demonstrate the effects of NIR-focused window technologies on heating and cooling loads in different climates.
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Can we make color switchable photovoltaic windows?
The development of smart windows could enhance the functionality of the large glass facades found in modern buildings around the globe. While these facades offer occupants views and natural light, the poor insulating qualities of glass cut against the desire for more efficient use of energy resources. In this perspective article, we explore recent developments for next-generation smart window technologies that can offer improved energy management through dynamic color switching, reducing heating and cooling loads, while also generating electricity through the photovoltaic effect. Approaches with chromogenic organic dyes and halide perovskite semiconductors have been developed for switchable photovoltaic windows, but each of these comes with unique challenges. These approaches are briefly discussed and evaluated with an eye to their future prospects. We hope that this perspective will spur other researchers as they think about the various materials and chemical design challenges associated with color switchable photovoltaic windows. Perhaps these initial demonstrations and research ideas can then become marketable products that efficiently use space to improve occupant comfort and reduce the energy demand of the built environment.
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- Award ID(s):
- 2128632
- PAR ID:
- 10465993
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 14
- Issue:
- 29
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 7828 to 7841
- 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
- Journal Article:
- https://doi.org/10.1039/D3SC01811C
