How Do Kettles Actually Work?

How Do Kettles Actually Work

More often than not, we find ourselves greatly depending on kettles to have our tea and coffee every morning and especially in cold seasons.

This is because it is fast and easy to use since you just have to put in the required amount of water, have it plugged in and then turn it on and wait.

Normally, it takes 4 minutes at the most to get the water ready for you to have a hot beverage. Simple, right? There is no need to start going through longer ways to have your water ready at boiling point when you can actually use a kettle and have it in a matter of minutes. If you still need to get one of these magical devices, we have put a handy guide together for the best kettles to buy when you have hard water here

But have you ever wondered to know exactly what happens in the kettle to produce hot boiling water?

Well, in this article, we are going to take you through what happens inside the kettle.

​How It Works

​The main part of an electric kettle is the heating element and without it, the kettle becomes nothing but a jug to hold water. The heating element which is made of a metal coil is located inside the kettle, usually at the base. To know the process the kettle takes to have the water boiling, you first need to plug the kettle to the mains and switch it on to start. Once switched on, electrical energy flows through the coil turning into heat. This, in turn, warms the water inside the kettle from the bottom. As the water gets warmer, it becomes less dense resulting in it rising to the top of the kettle. The process keeps repeating itself until the all water inside the kettle is heated.

The electrical resistance (the ability to stop the flow of electric current) of the coil is responsible for turning electrical energy into heat as it flows through the coil. As the element gets hotter, the heat is transferred to the cold water that is in contact with it.

kettles how it works

This heat is transferred through conduction and the water gets heated up rapidly. Using an electric kettle to boil water is usually fast because the water is enclosed in the kettle. Therefore, no heat is allowed to escape. When the heat is concentrated in a closed container such as a kettle, pressure rises faster due to the saturated vapor. This explains why the water boils much quicker than when using a pan or open fire.

When more heat energy is pumped into the bottom of a kettle, the water inside boils after some time. To boil an amount of water at the same temperature, equal amount of energy is required. The materials used in the construction of kettles have different specific heat capacity. If you have a kettle rated at 2100 watts, for instance, 2100 joules of electrical energy are being consumed per second. How fast the kettle takes to boil is determined by the amount of energy it uses. Heat energy can be added to the water quickly and efficiently provided it is enclosed in the kettle.

​How Electric Kettles Automatically Switch Off

​Since the invention of the electric kettles, there has been tremendous improvement from the original one to the modern kettle. Initially, it would require one to keep a close eye on the boiling water, failure to which, the heating element would burn out and blow a fuse. However, with modern kettles, electric components called thermostats have been incorporated to switch them off automatically when the boiling point is reached. A thermostat is designed to react to changes in temperature. It is built into the element unit and consists of a disc and two different metals held together so tightly. One of the metals expands faster than the other when there is a rise in temperature. The steam produced as the water boils hits the bimetallic thermostat and it makes an abrupt snap. The open thermostat then pushes a lever which, in turn, trips on the circuit to cut off the electric current. And that is how the electric kettle switches off on its own.


​An understanding of how electric kettles work enables you to know the safety measures you need to practice whenever you are using one. That’s not all. You also get to know just how long your kettle takes to have the water boil and why. Thanks to the advances technology, we now have kettles with thermostats to help reduce the risks of burning the kitchen or the whole house.

About the Author Catherine Wheeler

Hey, I'm Cath :) Iv'e got two beautiful young girls who mean the world to me. I used to be a head chef over at my local restaurant but I gave that up to look after my girls. I decided to put my culinary experience to use here by bringing that wealth of kitchen related knowledge and sharing it with you guys.