Freon Replacement Found: Air Conditioners and Fridges Set to Change
Air conditioning (AC) and refrigerator technology is preparing for a major transformation. After decades of relying on Freon as a refrigerant, the global industry is beginning to shift towards alternative materials that are far more environmentally friendly.
This radical transformation is driven by global commitments to reduce greenhouse gas emissions. Freon, which has long been a primary component in both AC units and refrigerators, has proven to have significant potential to trigger global warming.
To address this challenge, researchers have successfully developed an alternative method for cooling rooms without relying on hazardous chemical substances such as hydrofluorocarcium (HFC), commonly known as Freon. Instead, this cutting-edge innovation utilises salt as the core component of the cooling system.
How Salt-Based ‘Ionocaloric’ Technology Works
According to IFLScience, conventional cooling technology essentially works by absorbing and then discharging heat from a room using a specialised heat-conducting liquid. This liquid is then evaporated into a gas, circulated through a closed system, and finally condensed back into a liquid to repeat the cooling cycle.
While highly effective and the global industry standard for refrigerators, air conditioners, and water dispensers, the chemical materials used pose a serious threat to environmental sustainability.
In search of a solution, researchers from the Lawrence Berkeley National Laboratory and the University of California, Berkeley, have developed a new method for absorbing and transferring thermal energy. This model utilises physical principles where energy is stored and released as a material changes shape—similar to the process of ice melting into water.
As room temperature rises, ice melts and absorbs heat from its surroundings, thereby creating a cooling effect. However, researchers had to find a way to ‘melt the ice’ without actually raising the temperature. The solution was found by adding energy-charged particles called ions—similar to the method of spreading salt on snowy roads during winter to prevent ice formation. This innovative shape-changing cycle has been named the ‘ionocaloric cycle’.
“There has been no successful alternative solution that creates cold, works efficiently, meets safety aspects, and does not have a negative impact on the environment. We believe the ionocaloric cycle has great potential,” said Drew Lilley from the Lawrence Berkeley National Laboratory.
Claimed to be Zero to Negative Emissions
During the testing phase, the research team used a salt mixture made of iodine and sodium to melt ethylene carbonate. Interestingly, this liquid is produced by utilising waste carbon dioxide, making its production process not just zero-emission, but potentially negative-emission.
The results have been remarkable. In the experiment, temperatures were successfully lowered by 25 degrees Celsius using a power supply of only 1 volt.
Scientists are now focusing on designing practical systems so that this eco-friendly technology can be produced and applied commercially. One focus of development is identifying the most effective type of ‘salt’ to maximise heat absorption in rooms, where recent research suggests that nitrate-based salts are the most efficient candidates.