Radiative Cooling
Overview
Radiative cooling paint is a material that reflects solar reflectance across the UV-VIS-NIR range (0.25-2.5 µm) while emitting heat through the mid-infrared sky window (8-13 µm), allowing surfaces to cool below ambient temperature. The bilayer system combines a primer of titanium dioxide/ calcium carbonate composite particles, which provides 92.7% solar reflectance across the UV-VIS-NIR range (0.25-2.5 µm), with a porous silica aerogel topcoat that increases light scattering and opacity. This coating also achieves thermal emissivity around 96.3%, surpassing commercial white paints. Field tests showed the coating reduced surface temperatures by up to 21°C vs. uncoated panels and about 10°C vs. standard white paint, proving its potential to lower cooling energy demand and mitigate urban heat.
Main applications
The radiative cooling paint is suitable for cultural heritage buildings where non-invasive, reversible solutions are required. It preserves architectural appearance, reduces indoor heat without HVAC systems, and lowers surface temperatures by up to 10 °C, making it ideal for heritage sites in hot climates aiming for energy efficiency and net-zero carbon goals.
Performance
Main key performance metric: up to 10 °C reduction of the roof temperature as compared to the commercial white paint
Additional qualities:
- High solar reflectance
- High thermal emissivity
- High scrub resistance
- Water-based, PFAS- free, APEO- free, and formaldehyde-free
- All day Passive cooling
Excellent adhesion to multiple substrates (plastic, metals, and masonry)
Long term cooling performance
Experimentation - SINCERE Pilots
The radiative cooling is being tested in the two pilots where the effect of the paint is most important, in high temperatures, in Holon and Madrid.
Currently, August 2026, the experiments in progress but we can already report that in the closed experiment in Madrid, there has been measured a cooling of around 8oC.
Exhibitions
The radiative cooling paint innovation was featured at the SINCERE's booth at ECOMONDO, together with other exploirable results by the SINCERE project.
