Thermochromic smart windows toward climate-resilient and energy efficient buildings: from lab to applications.

Thermochromic smart windows (TSWs) exploit temperature-driven phase transitions to autonomously regulate solar and thermal radiation, offering a promising clean technology for reducing building energy demand and enhancing indoor comfort. Despite rapid advances in thermochromic materials, large-scale deployment of TSWs remains limited by coupled challenges in performance regulation, durability, climate adaptability, and architectural integration. This review examines the scientific and technological barriers that constrain the transition of TSWs from laboratory innovation to building-scale application. We first explored the fundamental trade-offs governing solar and visible light modulation, thermal emissivity control, and switching behaviors across diverse climatic contexts, and discussed how this performance requirements interact with long-term environmental stability. We then analyzed pathways for engineering translation, including scalable fabrication, integration within building systems and the implications of window behavior for occupant experience and operational control. Looking ahead, TSWs development is shifting from isolated material optimization toward spectrally intelligent envelope systems. Future progress will depend on standardized design guidelines, clear regulatory responsibilities for long-term service, and system-level integration with adaptive building control. These advances position TSWs as a component of climate-resilient building envelopes capable of contributing to cleaning thermal infrastructure in a warming world.