Color Changing Roof Tiles Could Save Hundreds in Cooling Costs

It’s a concept we all learn in grade school science—dark things absorb heat while light things reflect it. Because of that principle, black roof tiles are terrific at absorbing heat during the winter, but reduce energy efficiency and make it harder to keep your house cool in summer.

To address this problem, experts such as US Secretary of Energy Dr. Steven Chu recommend that homeowners in warm climates paint their roofs white. While that may be a clever move for some (providing their homeowners’ association approves), it doesn’t fully address the problem. In a perfect world, we would all have black roofs during cold times and white ones when it’s hot. Enter a team of recent MIT graduates and Thermeleon, their new green roofing concept.

Thermeleon is a roof tile filled with a “phase-change polymer gel” that changes color based on temperature. On hot days, the tile appears white and reflects roughly 80 percent of sunlight. But on warmer days, the tile turns black and reflects only 30 percent of sunlight. All of that translates into a roughly 20 percent reduction on cooling costs, which could translate into hundreds of dollars in lower utility bills per year.

The team is currently working on translating the method Thermeleon uses to change its color into a spray that can be applied to existing roofs, which makes it much more practical. No specific plans have been made to commercialize the concept yet, but the team does plan on working to bring the concept to reality. Here’s hoping it all works out.

Image via MIT

Comments

[Nick Dalby]

Mmmm, looks good but I can't see construction companies forking out for these. Better to invest in something like Cembrit slates that are maufactured to look like natural slate without diminishing natural resources.