The operating principle of an induction cooker is based on the law of the electromagnetic induction discovered by Michael Faraday in 1831. In simple words the principle can be described as follows: the alternating magnetic field gives rise to the inductive current or to the altering electric field.
In case of cooking stoves the above-mentioned principle works as follows:
Under the glass or glass-ceramic cooktop, there is a coil made of copper wire.
When electric current goes through the coil it transforms into an alternating electromagnetic field which, in turn, creates the inductive current.
location of the induction coil
When you put a pan with a magnetic bottom on an induction cooktop the pan serves as a conductor with a closed circuit.
The eddy current created by the stove makes the electrons in the ferromagnetic material of the pan’s bottom move.
When the electrons move they emit heat which heats up the pan and the food inside of it.
Advantages of induction as compared to ordinary electric and gas stoves
Ordinary gas and electric stoves use heating less efficiently. When you cook with a gas stove or an electric cooker only 30% to 60% of heat is directed at heating up the cookware. All the rest is wasted heating up the air in your kitchen.
The induction cooktop heats up only the bottom of the cookware, that is why it is more than 90% efficient.
The glass cooktop itself is heated up only due to the contact with the bottom of the cooking vessel. That is why it never becomes very hot.
Also, using the induction stove you will cook much quicker.
Is induction cooking safe?
Induction stoves are safe. The magnetic field created by them is not strong. It works so that it hardly penetrates into the bottom of the cookware. The magnetic field does not affect the food by any means. The food is heated up by the hot bottom of the cookware. Nonetheless, though the induction stoves have passed all safety tests some people are still afraid of radiation hazards. In any case, if you want to avoid the undesired exposure dangers it will be reasonable not to spend too much time standing very close to a working induction stove.
Another important safety advantage is that the coil will not start working if there is no cooking vessel on it which has a suitable size and is made of a suitable material. Some induction stoves can even detect how full the cookware is, therefore, you will not be able to switch on the stove with an empty pan on it.
To be suitable for induction cookers the cookware should have a certain diameter. As a rule, it should be no less than 12 cm or half the diameter of the heating plate. So, if you drop a coin or a fork on the cooktop nothing will happen. The cooktop simply will not be working.
Due to these properties, induction stoves are safe and economical. The cooktop will never work in vain or waste any energy. Even if you lift the pan for a few moments the special sensors will switch off the current. The cooktop is heated only due to its contact with the bottom of the cookware. It never gets hotter than 50°C-60°C. Therefore, you will not burn your fingers if you accidently touch the cooktop. This property is especially useful if you have small kids who often have accidents with hot stoves. Also, if you drop or spill something on the induction cooker it will not be burnt either.
In this regard, operating an induction cooker is much safer than using a gas stove or a traditional electric cooker.
However, induction stoves also have their disadvantages
Disadvantages of the induction cooktops
Induction stoves are very expensive though some de luxe models of electric stoves can have the same price.
Induction stoves need special cookware. In theory, any cooking vessel with a ferromagnetic bottom will work with such stoves. However, a lot of seemingly suitable pans have a very thin bottom. The best option is a cookware with a thick magnetic bottom. Glass, ceramic or aluminum cookware is unsuitable for induction cooktops.
Most induction cooktops should not be placed over other appliances which have metal elements, though some makers have already dealt with this problem.
Despite the described disadvantages the induction cookers are rather superior to other types of stoves by many characteristics. So, if you plan to replace your old stove consider buying an induction cooker. Even its high price will be justified by its useful characteristics and a long operating life.