Modern technology is indeed wonderful, and this array of new roofing solutions from Fast Company rolls out some of the latest additions to that wonderment.
“MIT's Thermeleon material is a composite of layers that makes it thermochromic--on exposure to heat it changes color from black to white. It works by sandwiching a common polymer between flexible plastic layers, with a black one at the back--when cold the polymer solution stays dissolved and the black rear face shows through, and when it heats up the solution condenses to form light-scattering droplets.
“The upshot is that when the sun is shining a roof tile covered in the material is white-colored, scattering up to 80% of the sunlight back and thus keeping the building beneath the roof cooler. The result is a 20% reduction in cost to keep the interior at a comfortable temperature in the summer, a figure which also comes with an eco-friendly drop in the electricity supply demands. During winter, of course, you'd prefer your roof to capture as much heat as possible from the sun, which is where the black coloring is handy--the tiles scatter just 30% of incoming solar radiation then.
“The team's working on micro-encapsulating the chemicals, so that in future they may work as a paintable or spray-on coating, and then if the prices drop to match the innovation, the tech could also find much use in the developing world.”