World · India Bureau
New polymer coating keeps surfaces cool without electricity or pigments
Engineers have developed a revolutionary pigment-free coating that can cool building surfaces below ambient air temperature, potentially offering a sustainable solution to urban heat in South Asia's scorching climate. The technology uses nano-to-microscale air voids instead of conventional white pigments to reflect sunlight and radiate heat skyward.
LSN India ·
Researchers at Columbia Engineering have created an innovative porous polymer coating that achieves significant passive cooling without requiring electricity or traditional reflective pigments. The coating works by incorporating microscopic air gaps throughout its structure, which scatter incoming solar radiation and allow trapped heat to escape toward the atmosphere.
Field trials demonstrated the coating's effectiveness across diverse climates. When tested in Arizona's arid conditions, surfaces coated with the material remained approximately 6°C cooler than the surrounding air temperature. Notably, tests conducted in Bangladesh showed the coating achieved a 3°C temperature reduction, suggesting the technology's applicability across South Asia's varied climate zones.
The development addresses a critical challenge for the region, where urban heat islands and rising temperatures burden cooling systems and energy infrastructure. By eliminating the need for electricity-dependent air conditioning or reflective paint pigments, the coating offers a low-cost, maintenance-light alternative for cooling rooftops, walls, and other exposed surfaces.
The porous polymer approach represents a departure from conventional cooling methods, relying instead on physics-based principles of light reflection and thermal radiation. As cities across India and Southeast Asia grapple with intensifying heat waves and energy demands, such passive cooling technologies could play an important role in sustainable urban development and climate adaptation strategies.