Synergistic modulation of solar and thermal radiation in dynamic energy-efficient windows

• Published in: Nano energy 2022-03, Vol.93, p.106865, Article 106865
• Main Authors: Zhou, Zhengui, Fang, Yunsheng, Wang, Xin, Yang, Erqi, Liu, Rong, Zhou, Xishu, Huang, Zhen, Yin, Hanzhi, Zhou, Jun, Hu, Bin
• Format: Article
• Language: English
• Subjects: Dynamic window; Energy savings; Light modulation; Sequence photonic structure; Thermal management
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2021.106865

Current technologies about the dynamic window in buildings, vehicles, and greenhouses primarily focus on solar radiation modulation for interior lighting, heating and cooling regulation. Mid-infrared thermal radiation of windows, as another important factor for interior thermal load, can be dynamically optimized to further improve energy efficiency. However, it is challenging to achieve synergistic solar and thermal radiation modulation of a window for optimal energy efficiency management. Herein, based on the estimation of the energy-saving potential of a midrise building by controlling the window emissivity, we propose an energy-efficient dynamic window that can synergistically modulate solar and thermal radiation. The prototype of such windows with sequence photonic structures could perform the function of synergistic multiband modulation by loading mechanical strain, and achieve a broad modulation ranges up to 55% in solar transmittance and 25% in mid-infrared thermal emittance. The dynamic window can regulate the steady-state interior temperature of a chamber up to ~4 °C in real-time testing, which could potentially provide annual energy-saving from ~45.5 to ~166.5 MJ m−2 for a typical midrise building located in 11 cities around the world. The intelligent dynamic window system with fast response to the changing weather can further improve home convenience, comfort and artistry and realize an energy-saving residential setting. Synergistic modulation of solar and thermal radiation for energy-efficient dynamic windows is realized by mechano-responsive sequence photonic structures, which can achieve broad ranges up to 55% in solar transmittance and 25% in mid-infrared thermal emittance. Real-time temperature testing demonstrates a steady-state regulation of ~4 °C, and simulation results show the total energy savings range from 45.5 to 166.5 MJ m−2 year−1 in 11 cities around the world. [Display omitted] •The importance of emissivity regulation of windows in energy saving is elucidated.•The stretchable film with quasi-orthogonal sequence can synergistically modulate solar and thermal radiation.•The mechanism of dynamic modulation based on sequence structures is validated by theoretical analysis.•The energy-saving potentials worldwide by using the proposed dynamic windows are evaluated.