US: New transparent canopy brings down outdoor temperature by 10°F

Engineers at UCLA have developed an innovative, lightweight, and scalable outdoor cooling structure that reduces radiant temperature by about 10°F without obstructing visibility. The system combines water-cooled black aluminum panels with a transparent, infrared-reflective polymer film, creating a semi-transparent canopy that actively cools the space beneath it. Field trials on campus and at the San Fernando Swap Meet demonstrated that this “cooling tent” lowered mean radiant temperature to approximately 78°F—significantly cooler than typical shaded areas and even below the ambient air temperature. Unlike traditional opaque cooling panels that block sightlines and raise safety concerns, this design maintains an open feel while effectively wicking heat away. The structure works by circulating chilled water through hydronic panels painted black to absorb stray heat, including body heat, while the polymer film reflects infrared radiation toward the sky. Participants consistently reported feeling cooler and more comfortable under the canopy compared to nearby shaded spots. Supported by the National Science Foundation and UCLA’s Sustainable LA Grand Challenge,