Scientists have developed a magnetocaloric heat pump eliminating refrigerants, paving the way for eco-friendly heating and cooling.
Researchers at the U.S. Department of Energy’s Ames National Laboratory has achieved a major milestone in sustainable heating, ventilation, and air conditioning (HVAC) technology by designing a magnetocaloric heat pump that matches traditional vapor-compression systems in weight, cost, and performance. Unlike conventional systems that rely on harmful refrigerants, this innovation offers a cleaner, environmentally safer alternative.
Traditional heating and cooling systems use refrigerants that significantly contribute to global warming and release harmful chemicals when leaked. The newly developed magnetocaloric heat pump operates without refrigerants, using magnetic materials to achieve energy-efficient heating and cooling. This technology could appeal to environmentally conscious homeowners, industries focused on reducing carbon emissions, and organizations in search of greener alternatives for HVAC systems.
Julie Slaughter, the project lead, shared insights into the development process: “We first looked at what is out there, and how close the existing magnetocaloric devices are to matching compressors. Next, we developed a baseline design and then asked, ‘Okay, now how far can we push the technology?’”
The pump’s operation relies on altering the magnetic field around magnetocaloric materials, paired with fluid circulation to transfer heat. A crucial innovation involves the use of spinning permanent magnets and magnetic steel, designed to maximize power density while minimizing material usage. This efficient configuration ensures the pump competes with the power output of existing compressors.
In their research, the team evaluated gadolinium and lanthanum-iron-silicon-hydride (LaFeSiH) materials, commonly used in magnetocaloric systems. While gadolinium simplifies device design, LaFeSiH materials offer superior power density. However, their limited availability and complex integration remain challenges for widespread adoption.
To enhance affordability, the researchers prioritized reducing the mass of permanent magnets and steel, which constitute most of the device’s weight. “We were able to show that we are competitive with the power density of some of the compressors out there today,” Slaughter noted.
By eliminating refrigerants and achieving cost efficiency, this breakthrough heat pump represents a significant step toward sustainable, eco-friendly heating and cooling technologies. It has the potential to serve a broad audience, from residential users to industrial players, aiming for greener solutions.
