Ferromagnetism. Energy efficiency. Safety. And the science of induction stoves visualized.
Induction cooking works because of the amazing combination of alternating currents, electromagnetism and resistance.
Induction stoves work because heat is directly generated in the base of the pot (pan) via electromagnetic induction (read all about it in this 1-Minute NomNom “Saying goodbye to the old flame“).
This creates an important requirement: The pot must contain material that allows this to happen.
Such a material must hence be ferromagnetic, i.e. it can be magnetized, attracted to or repulsed by magnets. A good example is iron, which we all know from basic school science, can be easily magnetized.
This iron requirement helps to make induction stoves more energy efficient. As heating is in the pot base itself, there is no open fire or heating element that loses heat to the environment. Induction stoves use at least 84% of the heat generated for cooking. In comparison, gas stoves could lose as much as 60% of heat, with only 40% going toward cooking.
Moreover, the cooktop itself is not heated up (again because the heating is in the pot base). The video above is a wonderful demonstration of what this means: you can put your hand on it, or a piece of paper, and neither will burn nor catch fire. Only the part directly under the pot is heated up by conduction from the pot base, but usually not to red-hot temperatures.
This makes induction stoves safer to use — in addition to not having an open fire.
Make me your iron requirement by liking me to discover more. All you need is a minute a day to explore the world’s marvels through the phenomenon of food!