The interaction between color, light and temperature has long been the subject of scientific exploration. The color we perceive is the result of objects absorbing and reflecting light, with white having high reflectivity and black having low reflectivity. Using this scientific principle, Stanford University researchers have pioneered an environmentally friendly solution for regulating indoor temperatures and significantly reducing energy consumption, providing a promising alternative to traditional air conditioning systems. The breakthrough comes at a perfect time, as global demand for cooling and heating puts enormous pressure on energy resources and contributes to greenhouse gas emissions.
However, the environmental consequences of extensive use of air conditioners cannot be ignored. Especially as global temperatures rise, many of these cities have similar problems. The media we use (air conditioning) can cool our environment temporarily but increase the temperature in the long run.
Colorful paint—scientists’ “answer”
Last October, researchers at Purdue University made headlines when they invented white paint that reflects 97.1% of sunlight. Building on this achievement, the Stanford team went a step further and created a color palette that includes orange, yellow, blue and white. This range of pigments is designed to regulate temperature, keeping spaces cooler in the summer and warmer in the winter, reducing the need for excessive heating and air conditioning.
The significance of this invention cannot be underestimated. Heating and cooling currently consume about 13% of the world’s energy and are responsible for about 11% of global greenhouse gas emissions. Innovative coatings developed by Stanford University researchers could address this energy challenge, significantly reducing energy consumption and environmental impact.
The key to the success of these coatings lies in their unique composition. Unlike traditional paints, these new paints feature a two-layer design. The bottom layer uses aluminum flakes to form an infrared-reflective surface, while the ultra-thin, infrared-transparent upper layer is made of inorganic nanoparticles. This innovative structure enables the coating to reflect large amounts of mid-infrared light, which is a major contributor to heat absorption. This double-layer design has practical implications for both cooling and heating. For example, when paint is used on exterior walls and roofs, it reflects sunlight and prevents heat buildup. Conversely, when paint is used on interior walls, the underlying paint reflects infrared rays, helping to retain heat within the space.
