By Alex Whiting | February 17 2017
(Thomson Reuters Foundation) While Australians struggle to keep their air conditioners humming as a heatwave threatens to overwhelm the country’s power grid, U.S. scientists say they have found a way to cool homes without using electricity or water.
A team of engineers has developed a film which – when applied to a surface like a roof – reflects the sun’s rays back into space, while also allowing the surface underneath to shed its own heat.
The film, which is slightly thicker than aluminium foil used in cooking, is relatively easy to mass produce, they said in the journal Science.
“Just 10 to 20 square metres of this material on the rooftop could nicely cool down a … family house in summer,” said Gang Tan, an associate professor at the University of Wyoming’s Department of Civil and Architectural Engineering and a co-author of the paper.
The film could be also used to help cool power plants, and improve the efficiency and lifetime of solar panels, they said. In direct sunlight panels can overheat, hampering their ability to convert solar rays into electricity.
“Just by applying this material to the surface of a solar panel, we can cool the panel and recover an additional one to two percent of solar efficiency,” said Xiaobo Yin, co-director of the research.
“That makes a big difference at scale.”