To boil or not to boil, a kettle cost and running cost question.

gill5blue

I have 2 cups of coffee in the morning before I go to work.
I boil the kettle once, make a cup of coffee and put the rest of the water in a flask, when I want the second cup of coffee, I use the water from my flask.
AS I don't actually measure the amount of water I put in the kettle but not filled up-I do save on the second boiling of the kettle.
gill5blue 

onomatopoeia99

outtatune said:

Le_Kirk said:

You cannot brew a decent tasting cup of tea with water at less than 100 degrees C, in my opinion!

Well, you can't brew a decent tasting cup of tea with water at 100 degrees or more either, since that wouldn't be a liquid!

No.  Read about the enthalpy (or "latent heat") of vaporization. 

Liquids can be heated to their boiling point, and they stay at their boiling point (100C in the case of water at standard pressure) until all the liquid has evaporated.

grumbler

silvercar said:

You will need a very long extension lead if you are going to climb a mountain to save a few fractions of a penny to boil a kettle! 

You don't need any lead if you live their. We talked about brewing tea in the first place, not saving money. About 1% of world population live permanently at attitudes above 2500m. They brew tee too.

If you want to climb, it's more than 2000m in UK, not 200m.

Section62

GValue said:

Now you can purchase a kettle that will allow you to also heat water, without boiling it to say 50c, 70c, 90c as well as a rolling boil. 

These kettles have existed since the very first kettle was made.

The difference is that the latest ones do so automatically.

Those of a certain age will remember electic kettles which didn't switch themselves off when the water boiled, and that an "automatic kettle" which switched off when boiled was a premium product.

Since then folk seem to have lost the ability to turn a kettle off themselves when they judge it to have reached the right temperature.

So the marketing folk have hit upon a new (expensive) premium product they can sell to people in the interests of saving money.

I'm not saying these new multi-temperature kettles aren't useful - just that equal or better money saving can be achived with a little human effort, without needing the kettle to be smarter.

Section62

RG2015 said:

The water needs to be boiling but is it boiling before the steam starts forming? I guess I could try making the tea with water that has just started bubbling and see what is tastes like.

Steam will be forming long before the water boils.

Depending on the definition of 'steam' used, it could be formed as low as the triple point (0.01C).  With sufficient vacuum water can be boiled at 0C.

Water is weird stuff.

grumbler

Section62 said:

RG2015 said:

The water needs to be boiling but is it boiling before the steam starts forming? I guess I could try making the tea with water that has just started bubbling and see what is tastes like.

Water is weird stuff.

I don't see anything weird in terms of boiling/evaporation. Pretty much the same as other liquids.

Regarding steam, it's how kettles are designed. Most need big amount/flow of steam produced to trigger the OFF switch.

TheElectricCow

If I’m boiling a kettle I simply fill it with the exact amount of liquid I need (fill the cup then tip that in) and just switch it off myself once the water is up to the desired temperature. Takes maybe 30 seconds, there’s minimal wastage, and there’s no old water left sitting in the kettle afterwards.

That said, I’ll only use a kettle a handful of times per week as my hot drinks of choice typically come from a separate dedicated coffee machine which handles the whole affair of correct water volume/temperature with minimal intervention from myself.

Wouldn’t personally bother with a temperature controlled kettle but maybe there’s some value in it for those who prefer a more precise beverage making experience, wouldn’t think the cost savings are that great compared to the additional upfront cost of a fancy kettle vs a basic one. Reliability may also be a factor, presumably there’s more components that could go potentially wrong in a temperature controlled one.

Andy_L

gill5blue said:

I have 2 cups of coffee in the morning before I go to work.
I boil the kettle once, make a cup of coffee and put the rest of the water in a flask, when I want the second cup of coffee, I use the water from my flask.
AS I don't actually measure the amount of water I put in the kettle but not filled up-I do save on the second boiling of the kettle.
gill5blue 

However you used twice as much energy to boil twice as much water in the first place

GDB2222

My own motivation for having a temperature controlled kettle is nothing to do with saving money, I’m afraid.  

We drink a lot of herbal teas, and these brew nicely with 70C water. It also means the brew cools down to a drinkable temperature much more quickly than if we used boiling water. 

With “proper” coffee, I prefer the taste if the water is at 90C, rather than boiling. 

MACKEM99

1. We make a hot drink 2 or 3 times a day and any excess not water goes in a flask next to the sink.  The water in the flask is then used later to wash up.  I must admit it's a recent thing and would never have dreamed of doing it I until recent large electricity price increases.