Revolutionary New Refrigeration Method Discovered by Scientists
▼ Summary
– Ionocaloric cooling is a new refrigeration method that uses salt and phase changes to absorb heat, potentially offering a safer and more environmentally friendly alternative to current systems.
– Traditional refrigeration relies on fluids that evaporate and condense, but many refrigerants used today are harmful to the environment due to their high global warming potential.
– The ionocaloric cycle applies an electric current to move ions, shifting a material’s melting point to achieve cooling without raising temperatures, as demonstrated in experiments with a 25°C temperature shift using less than one volt.
– This technology could help meet international goals like the Kigali Amendment by reducing hydrofluorocarbon use, and it shows promise for zero or negative global warming potential when using materials like ethylene carbonate.
– Researchers are now focused on scaling the technology for commercial use and experimenting with different materials to optimize efficiency, safety, and cost for both cooling and heating applications.
A groundbreaking approach to cooling, known as ionocaloric refrigeration, promises to transform how we manage temperatures by offering a safer and more environmentally friendly alternative to conventional methods. This innovative technique could significantly reduce the ecological footprint associated with current refrigeration systems.
Traditional cooling relies on a cycle where a refrigerant fluid absorbs heat as it evaporates, then releases it when condensed back into a liquid. While effective, many of these refrigerants pose serious environmental risks due to their high global warming potential.
Scientists have now tapped into a different principle: the energy exchange that occurs during phase changes in materials. Just as melting ice draws heat from its surroundings, causing cooling, the ionocaloric method induces phase shifts using ions, electrically charged particles. A familiar example is salting icy roads to lower the freezing point of water; similarly, adding specific salts can alter a substance’s phase to achieve cooling.
Drew Lilley, a mechanical engineer at Lawrence Berkeley National Laboratory, emphasized the urgency of finding better solutions: “The refrigerant landscape presents a major unsolved challenge. To date, no one has delivered a technology that efficiently provides cooling, ensures safety, and avoids environmental harm. We believe the ionocaloric cycle, if properly developed, could fulfill all these objectives.”
Through theoretical modeling, the research team demonstrated that this cycle could match or even surpass the efficiency of existing refrigerants. By applying an electric current, ions are moved within the system, adjusting the material’s melting point and enabling precise temperature control.
In laboratory tests, the team employed a salt composed of iodine and sodium to melt ethylene carbonate, a solvent also used in lithium-ion batteries. Because this process can utilize carbon dioxide as an input, it holds potential not only for zero global warming impact but for a net negative effect. Applying less than one volt of electricity produced a temperature shift of 25 degrees Celsius (45 degrees Fahrenheit), outperforming other caloric cooling methods.
Ravi Prasher, another mechanical engineer involved in the project, highlighted the balance of key factors: “We aim to optimize three critical areas: the refrigerant’s global warming potential, energy efficiency, and equipment costs. Our initial data is highly encouraging across all these dimensions.”
Current vapor compression systems often depend on hydrofluorocarbons (HFCs), which have high global warming potential. The Kigali Amendment, adopted by numerous countries, commits to slashing HFC use by over 80% in the coming decades. Ionocaloric cooling could be instrumental in meeting these targets.
The next step involves transitioning the technology from laboratory prototypes to scalable commercial systems suitable for both cooling and heating applications. Researchers are experimenting with various salt combinations to identify the most effective materials for heat transfer. In 2025, an international group reported advances with nitrate-based salts that were recycled using electric fields and specialized membranes, aligning with earlier predictions from Prasher’s team.
“We’ve established a novel thermodynamic cycle that integrates concepts from multiple disciplines, and we’ve proven its viability,” Prasher noted. “The focus now shifts to extensive experimentation, fine-tuning materials and methods to overcome practical engineering hurdles.”
The findings supporting this new cooling method were detailed in the journal Science.
(Source: Science Alert)
