Hot and arid regions are characterized by intense solar irradiation and high ambient temperatures that impose persistent thermal loads on buildings, urban infrastructure, and high-power energy systems. These conditions increase cooling demand while degrading the efficiency, reliability, and lifetime of electronic and energy-conversion devices. Addressing these challenges requires advanced materials capable of controlling solar radiation, improving heat dissipation, and enabling efficient thermal management under extreme conditions. THERMOCOOL develops a materials platform for climate-resilient cooling and energy efficiency tailored to hot environments such as the Gulf region. Three complementary material families are explored. Thermoelectric materials provide localized solid-state cooling and heat-to-electricity conversion. Radiative cooling coatings passively reject heat through high solar reflectance and strong mid-infrared emission. Smart optical coatings, including thermochromic and electrochromic systems, enable adaptive control of solar transmission and thermal loads in building envelopes and greenhouse glazing. A key innovation lies in drawing inspiration from natural thermal regulation strategies. Nacre-like “brick-and-mortar” architectures can be replicated to develop engineered superlattices that enable precise control of thermal conductance while maintaining mechanical robustness. In parallel, data-driven tools (e.g., thin.qa) identify and translate additional nature-inspired principles into high-performance materials. The project bridges materials innovation and deployment. WP1 focuses on synthesis, characterization, and theory-guided optimization, incorporating biomimetic concepts such as nacre-inspired architectures. WP2 targets building integration, WP3 validates applications in agriculture, EV chargers, and data centers, and WP4 develops materials for high-performance liquid cooling.