**6. Conclusion**

The conventional gas compression refrigerators have been mainly used for refrigeration applications. Generally, such refrigerators are not power-efficient. In addition, gases used in these refrigerators causes harmful effects on the environments. This has led to the development of magnetic refrigeration technology. Over the last decade or so, magnetic refrigeration at room temperature has become the subject of considerable attention. This technology is based on the use of magnetocaloric effect: that is the response of a solid to an applied magnetic field which emerges as a change in its temperature. This technology is ultimately aimed at developing a standard refrigerator for home use. Unlike conventional refrigerators, magnetic refrigerators are cost-effective and environmentally friendly. Moreover, it is noiseless and power-efficient and requires low maintenance cost and atmospheric pressure besides that its machines are easy to design.

This chapter introduced the magnetic refrigeration technology. It began by providing some essential definitions and provided a detailed review of ten magnetic refrigeration prototypes which are available until now. The operational principle of this technology was explained in depth through the comparison with the conventional one. The chapter then moved on to investigate the study of the magnetocaloric material using the Molecular Field Theory. The thermal study of the magnetic refrigeration process using the finite difference method (FDM) was then explained with providing some useful simulation results. Finally, the magnetic study of magnetic refrigerators using the finite element method (EFM) was presented with some practical results.
