Researchers at Ames national laboratory create an innovative pump matching modern systems efficiency.
A novel magnetocaloric heat pump developed by the Ames national laboratory (AML) in the U.S. department of energy promises an eco-friendly alternative to conventional vapor-compression systems. This innovation not only matches the performance, cost, and weight of current heat pumps but also addresses environmental concerns linked to refrigerants.
Vapor-compression heat pumps, a century-old technology, are widely used but pose environmental challenges. These systems rely on refrigerants that contribute significantly to carbon emissions and pose health risks when leaked. In contrast, magnetocaloric heat pumps eliminate these emissions and operate with lower energy requirements. Their potential makes them ideal for industries, residential users, and energy-conscious businesses seeking sustainable and efficient heating and cooling solutions.
Julie Slaughter, lead author and associate scientist , AML, highlighted the team’s systematic approach. “We first looked at what is out there, and how close the existing magnetocaloric devices are to matching compressors,” she said. The team then designed a baseline heat pump to explore the potential of advancing this technology.
Magnetocaloric heat pumps function by applying a magnetic field to specialised materials while transferring heat using fluid. The device’s core features spinning permanent magnets and magnetic steel to optimise the magnetic field, significantly influencing power density. The researchers focused on using resources efficiently, reducing the volume of magnets and steel to ensure the device was lightweight and cost-competitive.
The study also evaluated two primary magnetocaloric materials: gadolinium and lanthanum-iron-silicon hydride. Gadolinium, simpler to integrate, served as the baseline material. However, Slaughter noted the potential of lanthanum-based materials: “lanthanum-iron-silicon materials have a higher power capability than gadolinium, they naturally increase the power density.”
Through these efforts, the team demonstrated that their heat pump’s power density rivals current compressors. “We were able to show that we are competitive with the power density of some of the compressors that are out there today,” Slaughter explained. The research marks a step toward affordable, sustainable heating and cooling solutions.
