As man learned to harness fire so the need to heat water would have been an early requirement. Vessels to hold the water and able to withstand the heat of the fire would not have been too far behind.
Kettles first appeared in China. Made from iron and placed on an open fires. Over time, as areas for cooking and kitchens started to appear so the kettle began to evolve with a flat bottom so they could sit on modern stoves.
All kettles are designed to boil water and for that water to used immediately. Kettles aren’t designed to keep the water at that temperature once removed from the source of the heat. Slowly the water inside loses heat and it begins to cool. To keep the water hot meant keeping the kettle on the source of heat. The water would have continued to boil until finally, if not closely monitored, all water in the kettle would have boiled away. A kettle with no water keeps getting hotter and hotter until it eventually melts. That kettle would have a hole where the base used to be.
The Electric Kettle
Although we now have electric kettles, introduced in the early 20th century, the design elements haven’t changed very much. Each kettle has a handle, a spout and a lid at the top for filling it with water.
Newer models are made from stainless steel and also from plastic materials, special engineering grade plastics able to withstand the high temperatures.
Electric kettles use a heating element, enclosed in a metal sheath. The higher the power rating the quicker the water boils. Because all of the heat produced by the element is inside the kettle, they tend to be more efficient than stove based kettles where some of the heat from the stove is lost and ends up heating the cast iron gas rings and surrounding air.
When the Kettle Boils
Stove kettles often come with a whistle, which is activated by the steam from the boiling water. This starts at quite a low volume and increases as the water boils more rapidly and produces more steam.
The whistle alerts you to the fact that the water has reached boiling point but doesn’t switch the kettle off. So if left alone all the water will boil away. A kettle with no water will be damaged be the continuous heat still being applied.
Electric kettles fixed that problem as they have a mechanism to switch off the kettle once the water has boiled. A bimetallic strip is used to flip a rocker switch so the power is cut to the heating element.
The Temperature Control Kettle
With the advance in micro electronics and the arrival of the microchip, traditional devices would be enhanced in ways that could never have been imagined just a few years ago. We all have smart phones that can play videos and which take photographs, cars that can guide us to our destination with aid of built-in SatNav.
So too the kettle, that simplest of devices whose prime function has been to boil water, has been given the a 21st century makeover. Now we have a device that has been enhanced to do more, yes it can still boil water but technology has taken the kettle beyond just boiling aspect.
Kettles have been given the ability to heat water to boiling point or any temperature in between. With the added benefit of keeping the water at the selected temperature for a long duration of time.
The humble kettle, which has been with us almost since man invented fire and which hadn’t changed for millennial, has in the space of a century advanced way beyond what most of us would have thought possible.
A device that which can heat water to any desired temperature from anywhere, with the use of a smart phone – who could have ever have imagined that?
You can read more about kettles here on this wiki