SolCold, an Israeli startup, is advancing a coating that leverages anti-Stokes fluorescence to reduce heat transfer from the sun. In this approach, the material emits light at a shorter wavelength than the incoming excitation light, effectively reflecting solar heat away from surfaces like cars, buildings, and other exposed structures. The concept hinges on managing heat at the nanoscale so that daytime heat buildup becomes less intense for occupants and equipment.
Industry interest is high. Global automakers, including Toyota and Volkswagen, have taken note of the technology as a potential way to curb interior temperatures and improve overall efficiency. To illustrate the coating’s potential, SolCold conducted a demonstration with two identical white hatchbacks placed in direct sunlight: one coated, the other uncoated. The uncoated vehicle rose to about 55°C, while the coated vehicle stabilized around 37°C. The difference is striking and demonstrates a significant reduction in heat absorption, though the exact figures can vary with vehicle design, interior materials, and climate conditions.
Another point of interest in the test results is the vehicle parked in shade. The interior temperature reached the mid-40s Celsius, illustrating that the coating can exceed the effectiveness of shade alone under hot sun exposure. While boxes for precise performance depend on interior volume, seating materials, and insulation quality, the core takeaway is clear: the coating has a meaningful impact on indoor temperatures, even compared to natural shade when sunlight is intense.
SolCold asserts that interior cooling can be lowered by a broad range, from roughly 20% to 70%, depending on the car’s interior size and configuration. By reducing the heat load, the climate control system can operate more efficiently, potentially cutting energy usage and extending battery life for electric vehicles. The company emphasizes that its formulation is non-toxic and free of rare earth elements, addressing common concerns about material safety and supply chain risk. The nanostructure responsible for the light scattering is designed to prevent glare or distraction to bystanders, ensuring the reflected energy does not interfere with adjacent drivers or pedestrians.
Launch plans place the coating on production vehicles within the year, with scaling considerations focused on compatibility with diverse car models and manufacturing processes. If adopted widely, the technology could become a standard option for new vehicles seeking to improve thermal comfort, reduce HVAC load, and enhance occupant health in regions with intense sunlight and heat. The approach aligns with broader industry goals to reduce energy consumption while maintaining comfort and safety for drivers and passengers.
Video reference: SolCold