Sun's out? Not a problem.
Say goodbye to your high-cost air conditioner for here's our favorite star to take over. Can you imagine not having the need to turn it on and increase your electricity consumption yet still not feel the irritating hot weather? Thank me later.
Yaron Shenhav and his colleagues from SolCold, a firm based in Herzliya, Israel may just have an answer. They've created a high-tech paint alternative that cools when exposed to sunlight. “It’s like putting a layer of ice on your rooftop which is thicker when there is more sun,” Shenhav says.
This follows laser cooling's counterintuitive principle in which striking certain materials with laser actually cools them by up to 150°C! “Heat from a building could be absorbed and re-emitted as light,” he says. “As long as the sun is shining on it, it would be continuously cooled.”
However, unlike laser light, sun's spectrum is broader. So, to solve this, researchers had to make a special material that could make it work on scattered light. With this, they were able to create a two-layered paint- an outer layer that acts as a filter and an inner one that converses heat to light for cooling. Successfully tested in lab, the paint works best on metal roof and over rooms with low ceilings.
This costs about $300 to coat 100 square metres. But with the expensive price comes an up to 60 per cent decrease of energy consumption. This doesn't just reduce you bills but saves the planet along the process. With the new paint, “buildings would be able to install much smaller air-conditioning units,” says Shenav.
This can even be helpful in knowing how to cool objects in space. “With our technology, heat is transferred through light,” says Shenhav. “Space applications are a big market for us.”
So, have you decided what will your new roof color be?
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