When U.S. Department of Energy seeks smarter AC systems with smaller carbon footprints

There are two billion air conditioners in use today around the world, accounting for roughly 20 percent of the world’s energy consumption. According to the International Energy Agency’s latest report on cooling, that number will triple by 2050.

It doesn’t take an engineer to understand the math. Under the stress of growing populations, more urbanized settlements, and a rapidly warming climate, air conditioners will need to work smarter—not harder—to both efficiently cool the planet and reduce the heat-trapping carbon they produce.

The U.S. Department of Energy (DOE) is banking that researchers at Maryland Engineering can help. Last year, the agency awarded UMD’s Center for Environmental Energy Engineering (CEEE) $7.2 million to fund the development of “out-of-the-unit” ideas for revolutionizing the energy-sucking inner workings of forced air that contribute to carbon output—such as heat pumps, compressors, heat exchangers, and refrigerants—making them smaller, lighter, and more efficient.

“When people turn on their air conditioner, they don’t think of it as contributing to carbon emissions,” says Research Professor Vikrant Aute, who, along with Minta Martin Professor Reinhard Radermacher and Research Professor Yunho Hwang, directs the Center for Environmental Energy Engineering (CEEE) at UMD. “They will spend $1,000 on a new iPhone, but it is hard to get that sort of enthusiasm for a more efficient air conditioner that will save hundreds of dollars in energy bills. “We want to make the iPhone of air conditioners.”

The CEEE researchers know what’s at stake. The carbon emission problem is a global one, says Aute, and will require new technologies that are at once innovative and accessible to all. Working with DOE to develop the Life Cycle Climate Performance evaluations for air conditioning and refrigeration systems—essential guidelines for assessing carbon emissions—CEEE has an established track record for developing the collaborations and best practices required for a global carbon-neutral approach. Through an international working group, emission guidelines are now being globalized. Over their 30-year history, CEEE has been the trusted research partner for top refrigeration manufacturers around the world, collaborating to develop new and novel technologies.

Federal and private partnerships are funding not just research but also the next generation: CEEE has trained more than 250 graduate students for research and industry so far. That community, says James Tancabel, a Ph.D. candidate who has worked with CEEE for six years, is integral to pushing ideas—and urgency—forward. “When you turn on the air conditioner to make it cold in your house, you have to make it hot somewhere else,” he says. “It takes experts in the field to help people see that impact, and to design for that future.”

Read about other CEEE projects funded by the U.S. Department of Energy in the fall 2022 issue of the Engineering at Maryland magazine.