Radiative cooling for long-term building energy efficiency: An experimental comparison of seven coatings

Radiative cooling coatings are widely used owing to their excellent cooling performance and energy efficiency. However, there is a lack of comprehensive research on their weather resistance, long-term performance and effects on building load. To fill this research gap, seven coatings were selected for experimental observation and simulation research. The results revealed noticeable differences among different coatings regarding anti-aging properties, cooling performance and building load reduction. Some coatings exhibited yellowing, cracking and peeling after weathering tests, accompanied by a decline in their radiative properties. Long-term tests showed that the cooling performance of all coatings gradually decreased due to natural aging, and the rate of decline was proportional to the weathering of the coatings. Building load simulations revealed the potential effect of coating selection on cooling and heating loads, thereby suggesting that different coatings should be selected based on actual usage scenarios in different climatic zones.