Cooling grey paint beats the urban heat

CAN a splash of grey paint help combat global warming?

In Los Angeles, where summer temperatures regularly surpass 38°C, workers are coating streets in special grey treatments in a bid to do just that.

The City of Angels, home to four million people, is the first major city to test the technology.

Normal black asphalt absorbs 80 to 95% of sunlight, while the grey reflects it – dramatically lowering ground temperature and reducing urban street heat.

During a demonstration of the technique, Jeff Luzar, sales director at GuardTop, which markets the product, showed how applying the paint could dramatically drop street temperatures after just one coat.

Los Angeles is the first city in California to test the treatment on a public road, after initial trials on parking lots, according to Greg Spotts, assistant director of the city’s Bureau of Street Services.

“Potentially there could be a huge market for cool products and, in fact, it’s part of a much larger economic trend where solutions for climate change could be the next great investments for the future,” he said.

The city will also monitor how Angelenos react to the newfangled asphalt – and how quickly the notoriously thick LA traffic dirties the grey coating.

George Ban-Weiss, an assistant professor of Civil and Environmental Engineering at the University of Southern California, said cool technologies show promise in reducing heat, but may have some environmental penalties.

“Research is working out whether the environmental benefits outweigh those penalties,” he said. – AFP