New solar-reflecting film can cool homes without air con - scientists

by Alex Whiting | @AlexWhi | Thomson Reuters Foundation
Friday, 10 February 2017 13:17 GMT

In this 2006 file photo, a boy casts a shadow on a sunshade as he stands next to his father on a beach in Vina del Mar city, 85 miles (137 km) northwest of Santiago. REUTERS/Eliseo Fernandez

Image Caption and Rights Information

Scientists say they have found a way to cool homes and power plants without using electricity or water

By Alex Whiting

LONDON, Feb 10 (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."

(Reporting by Alex Whiting @Alexwhi, Editing by Laurie Goering.; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, climate change, resilience, women's rights, trafficking and property rights. Visit

Our Standards: The Thomson Reuters Trust Principles.