Researchers in Australia have developed a groundbreaking outdoor paint capable of lowering surface temperatures by up to 6°C while simultaneously harvesting fresh water from the atmosphere.
Created by scientists from the University of Sydney in collaboration with the startup Dewpoint Innovations, the new coating aims to help cool buildings during extreme heat and address water shortages in dry regions.
A six-month trial showed that the paint can collect around 390 millilitres of water per square metre each day — enough for a single person’s daily drinking needs from just 12 square metres of coated surface.
“This technology not only advances cool roof coatings but also provides a sustainable, low-cost, and decentralized water source — crucial amid climate change and growing water scarcity,” said Professor Chiara Neto from the University of Sydney’s Nano Institute, who led the project.
She explained that while humid conditions enhance performance, the system can still generate dew in arid regions where nighttime humidity increases. “It’s not meant to replace rainfall but to supplement it — providing water when other sources run low,” she added.
The paint functions by reflecting up to 97% of sunlight and radiating heat away, which cools the surface enough to condense water vapour into droplets. When applied to sloped roofs, the droplets naturally roll into gutters for collection.
According to Dr. Ming Chiu, chief technology officer at Dewpoint Innovations, the paint’s porous structure ensures high reflectivity and durability “without the environmental downsides of pigment-based coatings.”
