The Self-Descaling, Energy-Saving Kettle

The quality of the tap water in the village where I live is quite good; however its carbonate hardness is rather high, too. Therefor I had a long, unfortunate relation with my electric kettle because it got scaly very fast, which is all the more annoying when, like me, you need quite a bit of boiling water for hot (and cold) tea.

My kettle is a cheap, cordless unit made from stainless steel, and I had to descale it about every two weeks, using cheap vinegar with all its inherent olfactory emissions.

Someone recommended a water filter jug. We decided to give it a try and purchased such a jug. Ms Piffpaffpoltrie is happy now with the clean, filtered tap water it produces. I for myself compared the plain tap water's taste with the one of the filtered water, but I admit that, culinary philistine that I am, I could not find any difference.

After all, the kettle doesn't develop a coat of scale when boiling filtered water, and this, for me, is reason enough for using a water filter.

1. Electric kettle – see the first picture. It doesn't have to be cordless, although that's a convenient feature. Mine is a cheap unit with a pot made from stainless steel, heated from below as most of them are. It was purchased many years ago from Landi, a chain of retail stores catering to the more rural Swiss regions.
2. Water filter jug. It's made by Brita, purchased, as luck would have it, from the same Landi store several years later – second picture. (By the way and totally off-topic, the Brita company is named after the founder's daughter).
3. Matching water filter cartridges. They are said to remove chlorine and its compounds as well as carbonate hardness (limescale), together with copper and lead residues. I found compatible filter cartridges at different locations and from different manufacturers, and at widely differing prices.
4. The original cartridges made by Brita are a bit expensive for my taste.
5. The ones offered by Landi are cheaper, but the ones I had tested were of questionable quality – I once had one that produced a coat of scale in my kettle even when having used it for one time only, no filtering effect at all! I complained about it and received a refund. They might be improved now, but I didn't have the nerve for testing them again since.
6. The best price/performance ratio that I found is delivered by the ones from dm-drogerie markt purchased in Germany – see the third picture.
7. These are the ones I have experience with, but there for sure are others.

By the way, I am not affiliated with or sponsored by any of the companies mentioned above.

Of course you know how to operate a faucet, an electric kettle, a filter jug and the corresponding filter cartridges, there is no secret behind that.

When using filtered water in my kettle, I easily recognise when the filter cartridge needs to be replaced; then, a thin, gray-ish scale residue starts to build up on the kettle's bottom that was, before, clean and shiny. The pictures above show first the sqeaky-clean bottom of my kettle after a full week of boiling filtered tap water (about 2-3 litres per day), then the bottom of the same kettle after having boiled just a half litre of unfiltered tap water for only once (!).

At my place, one filter cartridge can be used for about three weeks, depending on the amount of filtered water I use, both for boiling in the kettle or used otherwise. This will vary for your location, that is, it depends on the hardness of your water but also on how much filtered water you consume.

What to do, then, with the saturated, used-up water filter cartridges? I don't know about the situation in your country, but here I recommend bringing them to one of the larger retailers and throwing them into the correct hole in their recycling wall.

Even if I don't immediately replace the filter cartridge and some scale residue starts to grow in the kettle, I don't have to resort to the chemical hammer (such as a commercial descaling product, or, much simpler, cheap vinegar) right away. I simply insert a new cartridge into the filter jug and then use the kettle with the filtered water for, say, four or five times. The water filtered by the new cartridge completely dissolves the scale coat until the kettle's inner bottom is, again, clean and shiny.

I not only use the filtered water for the kettle, but also for my espresso machine, by the way. It automatically alarms me when it's time to descale it, and, believe it or not, this had to be done for the first time after more than three full years of use!

To be honest, the kettle in itself cannot save energy, quite the opposite. Producing heat from electricity always requires a lot of the latter, regardless of what type of device is used. My kettle, for example, consumes 2 kW (that is, 2000 Watt). The only way to save energy with such a device is by keeping it always in pristine condition and using it for as little time as possible. Changing one's habits can help in doing so – in small amounts only, I admit. But imagine how much energy could be saved on a global scale, in millions or even billions of small amounts!

1. Any layer of scale within your cookware acts as a thermal insulation, increasing the amount of energy required for, e.g., boiling water. Keeping your kettle free from scale is a very simple method to save energy. Filtered water helps you to do so, and in a comfortable way, at that.
2. There are people who usually fill their kettle to the max, even if they only need a cup of hot water. Still worse, they sometimes leave the remaining water in the kettle, letting it cool down, and then re-heat it for the next cup some time later. This is neither economical nor ecological – the more water you heat, the more energy is required, and the longer it takes.
3. If you only need one cup (or mug) of hot water, I suggest you measure the correct amount with your cup/mug and pour just that into the kettle. Again, the less water you heat, the less energy is consumed to do so.
4. Some people patiently wait until their electric kettle automatically turns off (most of the kettles out there can do that – the era of the whistling kettles is long gone). When this happens, the water has been boiling for quite some time because there is always some delay due to system inertia. Stay close to the kettle, or, better, busy yourself with something else in the kitchen, until you hear the water boil. Then switch the kettle off right away – because the water can not become hotter than boiling temperature, regardless of how much energy is put into it.

Now you want, of course, to know my preferred procedure for preparing cold tea (usually rosehip or herbal). I use a two-litre jug made from toughened glass that withstands temperature shocks, into which I put the tea bags and some honey, if desired. A smaller amount of water boils faster and so saves energy and time, therefor I make my kettle boil only a half litre of filtered water that I then pour into the glass jug. Once the tea bags have steeped for long enough, I remove them from the jug and add some more cold, filtered water, diluting the concentrated tea, rather than filling the whole jug with boiling water.