Summary:
UCLA researchers in the Department of Materials Science and Engineering have developed a ceramic tile-based material that can assist in passive cooling for buildings and other structures.
Background:
Passive radiative cooling (PRC) is a promising and sustainable way to cool buildings and outdoor structures. Due to global warming, there is increasing need to reduce energy consumption such as air conditioner (AC) usage. PRC is an inexpensive solution that can aid by passively cooling buildings which reduce heat island effects and AC energy consumption. Currently the two most commonly used radiative cooling designs do not fully satisfy technical requirements. Building coatings such as highly reflective white paints have a moderate-to-high solar reflectance but their cooling effect is limited and quickly degrade over time. Silver- and aluminum-based radiative emitters, while effective, are typically too expensive and intricate to be deployed on a wide-scale, degrade quickly, and have solar reflectance < 97%). Therefore, there is a need for novel designs of PRC materials that are durable, inexpensive, and easily manufactured.
Innovation:
UCLA researchers have developed a PRC ceramic material that helps to keep buildings cool while remaining affordable and durable. Compared to current market materials, this technology shows superior thermal and optical performances, being able to reflect up to 99% sunlight and higher amounts of downwelling long wavelength infrared radiation from the atmosphere. Since the invention does not use exotic materials or complex manufacturing process, it is an affordable solution and is easily scalable. Its smooth surface limits particle accumulation, making it effective in locations with high air pollution. The innovation also boasts excellent thermal conductivity and can also be deployed in industrial processes such as water-cooling processes to transfer excess heat.
Potential Applications:
- Passive cooling surface for buildings and other structures
- building facades and roofs
- water cooling panels
- refrigeration
- thermoelectric power generation
- water vapor condensation
- freezing desalination.
- Vehicles.
- Reflectance Standards
- Water Cooling Processes
Advantages:
- High cooling performance
- Thermal and optical properties
- High operation durability
- Easy fabrication & implementation
- Low cost
Status of Development:
First successful demonstration (first actual reduction to practice) has been accomplished
Related Materials:
J. Mandal, S. Mandal, J. Brewer, A. Ramachandran, A. Raman; “Radiative Cooling and Thermoregulation in the Earth’s Glow”; arXiv:2006.11931, 2020