Electromagnetic energy has been employed for many years for industrial applications, including wood drying and bread processing. There are several ways in which electromagnetic energy can be applied, such as induction, radio-frequency (RF) or microwave. The main difference is the frequency at which these techniques operate. Depending on the material to be processed, the different frequencies can offer different levels of performance. Although RF and microwave operate in a similar way, microwaves can offer better uniformity. However, both RF and microwave are usually limited to dielectric materials with specific dipolar properties.