Study by McGill University, UCLA, and Princeton reveals sustainable alternative to air conditioning

A recent study by researchers from McGill University, UCLA, and Princeton examines a sustainable alternative to air conditioning.

Photo courtesy of McGill University

A recent study by researchers from McGill University, UCLA, and Princeton has revealed an inexpensive, sustainable alternative to mechanical cooling with refrigerants in hot and arid climates as well as a way to mitigate dangerous heat waves during electricity blackouts.

With the planet getting hotter, the need for cool living environments is becoming more urgent. However, air conditioning is considered a major contributor to global warming due to its units using potent greenhouse gases and large amounts of energy.

As a result, the researchers set out to find out how to achieve a new benchmark in passive cooling inside naturally conditioned buildings in places like Southern California that have hot climates.

The researchers examined the use of roof materials that radiate heat into the cold universe as well as how to combine them with temperature-driven ventilation. These cool radiator materials and coatings are often used to stop roofs from overheating.

While researchers have used them to improve heat rejection from chillers, there is untapped potential for integrating them into architectural design more fully, so they can drive regular and healthy air changes.

“We found we could maintain air temperatures several degrees below the prevailing ambient temperature, and several degrees more below a reference ‘gold standard’ for passive cooling,” said Remy Fortin, lead author and PhD candidate at the Peter Guo-hua Fu School of Architecture. “We did this without sacrificing healthy ventilation air changes.” This was a considerable challenge, considering air exchanges are a source of heating when the aim is to keep a room cooler than the exterior.

“We hope that materials scientists, architects, and engineers will be interested in these results, and that our work will inspire more holistic thinking for how to integrate breakthroughs in radiative cooling materials with simple but effective architectural solutions,” said Salmaan Craig, Principal Investigator for the project and Assistant Professor at the Peter Guo-hua Fu School of Architecture.