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ENVIRONMENT

Reflective roof paint repels the heat

Hyperseal paints can reduce the costs and energy needed for cooling by lowering the amount of heat a building absorbs from the sun. White roofs may be the new green.

July 15, 2009|Tiffany Hsu

On bright days, the rooftop of the Anaheim Hilton is so blindingly white that it looks like a mirror positioned directly at the sun. That dazzling glare might just be the greenest thing to happen to the top of a building since solar panels.

The white coating deflects nearly 85% of the heat that hits it, reducing the surface temperature by as much as 50 degrees. That means less energy is needed to cool the hotel's interior, cutting air-conditioning costs and carbon emissions.

This is no ordinary coat of paint. Designed by an 82-year-old former military scientist from the Inland Empire, the tinted topcoat is filled with tiny hollow glass balls that deflect heat, layered over a waterproof undercoat made of recycled rubber.

The Hilton spent more than $150,000 on the project, which was completed in March. That's $300,000 less than the cost of a conventional repair to the old, leaky roof, said Jerome Annaloro, director of property operations at the hotel. If the reflective material cuts utility costs this summer the way management anticipates it will, Annaloro said, he will recommend white roofs for the entire Hilton chain.

"I was skeptical at first . . . but the product spoke for itself," he said. "It's a win-win."

Americans spend about $40 billion a year to cool buildings, according to U.S. government figures. So-called cool roofs are being touted as a simple, inexpensive way of lowering surface temperatures on the tops of structures by as much as 100 degrees, cutting operating costs and slowing climate change.

Energy Secretary Steven Chu, a Nobel Prize winner in physics, recently called for all roofs to be painted white to promote saving energy. Some scientists suggest that covering dark tar roofs with light-colored coatings could help mitigate the "urban heat island" effect. Development has raised temperatures markedly in many cities, leading to more energy use and smog as well as greater numbers of deaths during heat waves, experts said.

But it will take more than the Hilton to make a dent.

"To change an entire city and save energy all the way around, you need to get to a critical mass," said Scot Horst, senior vice president of the U.S. Green Building Council's Leadership in Energy and Environmental Design rating system. "One or two buildings doesn't make that big of a difference."

Mass implementation of cool roofs in the 100 largest cities would offset 44 billion tons of carbon dioxide emissions, or the equivalent of taking 600 million cars off the road for 18 years, researchers at Lawrence Berkeley National Laboratory found last year. Some cities, including Chicago, already have ordinances that require light-colored roofs.

Skeptics say white roofs aren't always the eco-friendly panacea they're sometimes made out to be. The reflective component is most effective in sun-saturated regions like the Southwest. And it could lead to higher heating bills in the winter because the sun's warmth can't permeate the roof.

Still, the niche is booming. The Energy Department and U.S. Green Building Council are pushing cool roofs to consumers and developers. Entrepreneurs are developing a host of new products using metal, ceramic tile, reflective paints and coatings and even rooftop gardens to beat the heat. Among them is Ronald R. Savin of Rancho Mirage, a serial inventor and holder of nearly 20 patents, who developed the paint atop the Anaheim Hilton.

An engineer and retired Air Force colonel who spent much of his military career creating coatings for spacecraft and airplanes, Savin started his own paint company in 1957 and later sold it to a British conglomerate. He slowed down a bit when he reached his 70s, spending more time collecting first-edition books and ornate clocks and less time tinkering.

Then, three years ago, he saw a program on the History Channel about recycled rubber. Inspired, he returned to his lab and spent six months experimenting before making a breakthrough on a new paint.

His Hyperglass top coat is designed like a Rice Krispies treat. Glass "microspheres," which are used to lighten airplane parts and bowling balls, are suspended in a paint that includes Teflon. The whiter the titanium dioxide tint, the more heat bounces off.

Underneath, his Hyperflex primer serves as an insulation layer that also helps prevent water damage and erosion. And because it uses powdered recycled rubber, it helps address another thorny environmental issue: the millions of tires discarded annually in the U.S.

The paint could spawn "such a violent change in the paint industry that they won't know what to do," Savin said.

Hyperseal paints are free of harmful volatile organic compounds known as VOCs and are relatively cheap to produce, but the company's Palm Desert factory can make only 5 million gallons a year. Most large projects, such as bridges, require several hundred million gallons, Savin said. So he's looking to license his formula to other companies.

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