When you’re inside a building, whether it’s snowing or sweltering outside, the internal temperature probable only varies by four degrees. The Department of Energy says that, in practice, most offices, hospitals, houses and other buildings are kept between 71 and 75 degrees Fahrenheit to keep people comfortable.
“It’s really kind of ridiculous that we heat and cool a whole building for the comfort of a few people who don’t actually occupy that much space,” says Ellen Williams, the director of ARPA-E, the Department of Energy’s Advanced Research Projects Agency-Energy.
Heating, ventilation and air conditioning (HVAC) account for 13 percent of overall American energy consumption, and 40 percent of the energy used in a typical U.S. residence. To address any waste, ARPA-E started the DELTA (Delivering Efficient Local Thermal Amenities) program, which funds projects that design what they call localized thermal management systems. The idea is that if we can better regulate our personal body heat through things like wearables and targeted heating systems, we can use less energy to keep buildings at a comfortable temperature.
Some of those projects, like T-shirts lined with tiny fans, might seem far-fetched, but researchers have proven these concepts have the potential to cut a measurable amount of energy use. Emily Fritze, special advisor to ARPA-E’s director, says these kinds of technologies could potentially save 2 percent of the overall energy used in the U.S. The DELTA projects were on display at the recent ARPA-E Energy Innovation Summit. Here are some of the options that are closest to being in your closet or at your desk:
A Temperature Regulating Robot
RoCo, or the roving comforter, is a moving robot that regulates the temperature in your personal space. To follow you around, it tracks your phone, and then it blows hot or cool air at your face and feet. The idea is that by creating a bubble of heat or AC, you significantly reduce the HVAC waste that comes from heating, say, empty conference rooms. The tricky part in developing the RoCo wasn’t the tracking, which uses Wifi and face recognition, it was finding a way to dump the excess heat when the AC was cranking (think, the condensation on a swamp cooler). To address that, the University of Maryland team built in a canister of paraffin wax, which melts and acts as a heat dump when it gets hot. The RoCo can run for two hours, then the wax needs to resolidify. The researchers expect to have prototypes ready by April, and, through a partnership with GE, they hope to have commercial models, at a price point of about $60, available by 2018.