Scientists at the University of Sydney have developed a coating that addresses two critical climate challenges simultaneously. Working alongside startup Dewpoint Innovations, the team created a nano-engineered polymer that reflects up to 97 percent of sunlight, cooling building interiors by as much as 6 degrees Celsius without energy-intensive air conditioning.
The innovation goes beyond temperature control. The coating's microscopic porous structure creates ideal conditions for atmospheric moisture to condense into droplets on the cooled surface, similar to how steam forms on a bathroom mirror. During six months of rooftop testing at the Sydney Nanoscience Hub, the material captured dew on more than one-third of all days, producing as much as 390 milliliters of fresh water per square meter.
According to Professor Chiara Neto, who led the research, the technology opens pathways to sustainable and decentralized fresh water sources in the face of climate change and growing scarcity. While humid conditions optimize performance, dew formation can occur even in arid and semi-arid regions where nighttime humidity rises. The harvested water serves multiple purposes, from providing drinking water for animals and irrigation for high-value crops to cooling through misting systems.
The coating maintains its effectiveness in harsh conditions and can be applied using standard rollers or sprayers. Dewpoint Innovations is now developing a water-based formulation for commercial production. The cost is expected to be slightly higher than premium paints, making it accessible for widespread adoption in heat- and water-stressed regions worldwide.