In the realm of refrigeration and cooling technologies, a quiet revolution is underway and it’s powered by permanent magnets. For over a century, traditional refrigeration systems have relied on vapor compression; however, the environmental concerns of the 21st century have sparked a search for more sustainable alternatives. Magnetic refrigeration, with its promise of reduced energy consumption and minimal environmental impact, is a promising contender. 

Magnetic Refrigeration & Magnetic Moments

Magnetic refrigeration is a cooling technology that leverages something called the magnetocaloric effect. This occurs when a magnetic material heats up when exposed to a magnetic field and cools down when it’s removed. The key to this phenomenon lies in the alignment of magnetic moments. In electromagnetism, “magnetic moment” refers to the strength and orientation of a magnet that produces a magnetic field. Exposed to a magnetic field, these moments align, causing the material to heat up. When the field is removed, they randomly reorient, causing cooling. 

Where Permanent Magnets Come Into Play

Research shows that permanent magnets play a pivotal role in magnetic refrigeration systems by providing magnetic fields. 

 

Let us break it down:

 

Magnetic heat transfer fluids: In a magnetic refrigeration system, a heat transfer fluid containing paramagnetic or ferromagnetic particles is cycled through a series of magnetic fields generated by permanent magnets. The particles heat up and then cool down as they move in and out of the fields. This transfer of heat cools the refrigerator’s system.

 

Adiabatic demagnetization: This is another method in magnetic refrigeration. It involves placing a paramagnetic salt (e.g., gadolinium sulfate) in a magnetic field generated by permanent magnets. The salt heats up as the magnetic moments align, and then the magnetic field is gradually demagnetized. As the moments randomly reorient, the salt cools. Then it can be used to cool the desired space/material. 

Industries That Could Benefit From Magnetic Refrigeration

While magnetic refrigeration isn’t as widely used as traditional vapor compression, ongoing research efforts are being made into real-world applications. 

 

Here are ways magnetic refrigeration could be used: 

 

  • For laboratory and scientific use
  • Medical refrigeration (e.g., biological samples, vaccines, medications)
  • Space applications (gravity can complicate traditional refrigeration systems)
  • Food and beverage industry
  • Air conditioning and household refrigeration 
  • Green technology

Apex Magnets Is Cool!

Permanent magnets are at the forefront of the magnetic refrigeration revolution! As researchers continue refining magnetic refrigeration technology, we can hopefully look forward to a greener, cooler future! At Apex Magnets, we’re excited by these kinds of magnetic innovations! And we’re committed to providing a wide range of magnetic products in various shapes and strengths, including neodymium magnets in blocks, discs, cylinders, and rings. If you have questions send us a message, or call us at 1.304.257.1193.