Building energy consumption constitutes approximately 40% of total energy usage in the US. zero energy buildings (ZEBs) have received much attention in the last decade as they can alleviate some of the negative impacts that buildings have on the environment. New materials and systems are emerging that can help regulate building enclosure heat losses and gains in a passive manner, possibly leading to more cost effective ZEBs. A novel thermo-optically responsive solid–solid phase change material (SS-PCM) coating has been developed to help offset heat gains or losses in building enclosures. The study investigates the optical and thermal processes of the SS-PCM, as well as the synergies among different layers within the enclosure system, through a series of numerical simulations. The impacts of the solar incoming angle and phase transition temperature on the absorptivity of the SS-PCM, which have a significant influence on the optical and thermal transfer processes, are explored. The feasibility and benefits of using the SS-PCM system in building enclosures under both warm and cold climates are investigated. Simulation results: (1) confirm the potential of the SS-PCM coatings to reduce undesirable heat exchange through building enclosure in all orientations and identify the roof as the preferred location of installing the SS-PCM system; (2) substantiate the thermal benefits of the system throughout the year and determine the optimal phase transition temperature of the SS-PCM with maximal energy saving; and (3) demonstrate more thermal benefits and energy saving of the SS-PCM coatings in warm climates compared to cold climates, which has been a challenge for most of existing passive solar facades.

在美国，建筑能耗约占总能耗的 40%。零能耗建筑 (ZEB) 在过去十年中备受关注，因为它们可以减轻建筑对环境的一些负面影响。新材料和系统正在出现，它们可以帮助以被动方式调节建筑外壳的热量损失和收益，可能会导致更具有成本效益的 ZEB。一种新型的热光响应固-固相变材料 (SS-PCM) 涂层已被开发出来，以帮助抵消建筑外壳中的热量增加或损失。该研究通过一系列数值模拟研究了 SS-PCM 的光学和热过程，以及外壳系统内不同层之间的协同作用。探讨了太阳入射角和相变温度对 SS-PCM 吸收率的影响，这对光学和热传递过程有重大影响。研究了在温暖和寒冷气候下使用 SS-PCM 系统建造围护结构的可行性和好处。模拟结果： (1) 确认 SS-PCM 涂层在通过建筑围护结构在所有方向上减少不良热交换的潜力，并将屋顶确定为安装 SS-PCM 系统的首选位置；(2) 证实系统全年的热效益，确定节能最大的 SS-PCM 的最佳相变温度；