The brainy idea of “smart” roofs

I’m sitting in my cousin’s living room in the beautiful hills of Hillsborough, Calif., outside of San Francisco and my wife and I agree we must do the unthinkable: We must ask him to turn the heat thermostat higher. This request is coming from two people who hate hot weather and, in the winter, keep their home at 67 degrees by day and close to 60 at night. It is now noon in my cousin’s living room and the indoor thermometer is frozen at 62.

It turns out Phil and Arlene like it cold and they also like to save on energy. Going green is a good thing. And I am really impressed when Phil tells me the solar panels on their roof are more than 25 years old. They surely have been at the forefront of the energy-saving movement in this country. But since it’s springtime in California and we didn’t bring winter coats for this visit, he relents and turns the heat way up to 64 degrees.

One of the reasons Eileen and I are visiting is that the American Chemical Society has just completed a successful 239th National Meeting in the City-by-the-Bay. And speaking of the environment, I love one of the news releases that we produced for the meeting last month. It described the new notion of “smart roofs.”

Top a building with a light-colored “cool roof,” and it reflects sunlight, cutting air conditioning bills in the summer, but increasing winter heating costs.  Choose black shingles, and the roof soaks up sunlight to cut winter heating costs but makes the roof bake in the summer sun.  One or the other. You can’t have it both ways.

Until now.

Scientists have reported the development of a “smart” roof coating, made from waste cooking oil from fast food restaurants, that can “read” a thermometer. The coating automatically switches roles, reflecting or transmitting solar heat, when the outdoor temperature crosses a preset point that can be tuned to the local climate. Roofs coated with the material would reflect scorching summer sunlight and reduce sticker-shock air-conditioning bills. When chilly weather sets in, the coating would change roles and transmit heat to help warm the interior. 

“This is one of the most innovative and practical roofing coating materials developed to date,” said Ben Wen, Ph.D., leader of the research project.  He is the vice-president of United Environment & Energy LLC in Horseheads, N.Y. “This bio-based intelligent roof coating, compared with a traditional cool roof, could reduce both heating and cooling costs as it responds to the external environment.  It will help save fuel and electricity and reduce emissions of volatile organic compounds from petroleum-based roofing products.  In addition, it will provide a new use for millions of gallons of waste oil after it is used to cook French fries and chicken nuggets." To read more, go to smart roofs.

 

Image courtesy of Dr. Ben Wen