Researchers at Oregon State University have invented a new blue pigment that could help make buildings more energy efficient. The pigment, dubbed“Cool Blue,” is able to reflect 40 percent more light than other blue pigments, keeping building surfaces, especially roofs and walls, cooler.
Cool Blue, like other cool-roof coatings, works by reflecting more sunlight than traditional pigments and materials. When more of the sun’s light is reflected, less is absorbed into the roof, keeping the overall temperature of the roof and the building lower.
For the same reason that we usually wear white in the summer, most currently available reflective coatings are lighter colors. However, Cool Blue is uniquely able to reflect more light than other dark pigments. Researchers theorize that pigment’s peculiar pyramid-like molecular structure allows it to reflect not only more visible light, but infrared and ultraviolet light as well. By reflecting a wider variety of light, Cool Blue remains cooler–even in direct sunlight.
Studies have suggested that maintaining a cool roof can significantly lower both a building’s annual cooling cost as well as its overall energy consumption. As many reflective materials and coatings can be bought for prices comparable to “traditional” (less-reflective) materials, cool roofs offer a cost-competitive way to improve a building’s overall energy efficiency.
The EPA has also suggested that cool roofs could be a way to manage and reduce “urban heat islands,” in which dense urban centers experience higher average temperatures due to city building materials absorbing and retaining heat. This means that, if widely adopted, cool roofs could reduce a building’s cooling costs and energy consumption, as well as aid in keeping cities and urban centers cooler. Cool Blue, which researchers claim can be produced cheaply and in an environmentally responsible way, is expected to be commercially available within a few years.
– Posted by Scott Brennen, 2012 Green Plus Fellow