“Because this is the immediate layer to your skin, the response time is much, much faster than you cooling the air,” says Cornell electrical engineering professor Edwin Kan, who works on the project.
This device is worn, so it has to be comfortable. That’s the job for Tasha Lewis, a professor in Cornell’s Department of Fiber Science and Apparel Design. She’s been talking with potential users about their needs for the style and fit of the garment. For instance, where would the heating unit go on a woman who isn’t wearing a belt? Currently, the device is pretty bulky for something that hangs on your body all day, but is there a way to transform that device into a fashion statement in its own right?
The garment could be particularly appealing for menopausal women, Lewis says, because it can adjust to body temperature fluctuations within seconds. More broadly, it could be the special something you pull out for your most high stress situations—the big interview, meeting with a major client—or just when you don’t want to show up to work on a hot day sweating profusely.
“It’s our way to say, you can control how comfortable you are, wherever you are—even if you’re standing on the subway, or if you’re in your office, or if you’re just running,” Lewis says.
Elsewhere in adaptive clothing, a group from Otherlab, a private research institute in San Francisco, is designing fabric that expands and contracts based on heat, creating a thicker garment in the cold and thinner in warm settings.
Common materials like nylon, polyester, cotton, and spandex respond differently to changes in temperature, senior R&D engineer Jean Chang explains. The team combines different materials so that when exposed to a drop in temperature, the fabric puckers into a bunch of tiny dimples, which trap air and improve insulation. They’re still working on a clothing-sized prototype, and this technology is more promising for outerwear than for base layers, but it could be a great way to survive those days that switch from cool to warm before you get home to change. Or, for that matter, for an office that always wavers between comfortable and too chilly.
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The most shovel-ready personal heating system at the ARPA-E convention was a magical office chair from the Center for the Built Environment at UC Berkeley. It looks like a typical upscale ergonomic chair. This model, though, has a heating element and a fan in both the seat and the back. A control panel on the side only turns on when someone sits down, at which point the user can independently control the bottom and back for their desired heating or cooling. If your back is sore, for instance, you could lightly warm it up while keeping your base cool.
Portable heating elements and fans already exist, but this chair trounces them in efficiency. Full heating capacity uses 14 watts and full cooling capacity uses 3.6. Compare that to many personal heaters on the market now, which use up to 1,500 watts. This efficiency matters for the system-wide greenhouse emissions: The solution to current energy waste can’t consume more than it saves.