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artie

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my father used to talk about having heat exchangers in the sink wastes, to capture all the wasted heat from the vegetable boiling water..
Can't believe a Yorkshire man pouring all those nutrients down the drain so he could recapture a little heat.

Much better made into gravy.
 

artie

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These arguments about 'only boiling what you need' doesn't apply in the winter when you've got the heating going. Any heat left over in the kettle will transfer to the house environment and, if you've got thermostat control, the CH output will reduce in accordingly.
Brian
Just like I've always questioned the reasoning of replacing old style incandescent bulbs with low energy types. The CH just has to work harder.
 

MARK.B.

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Switched to a Breville(other makes available) kettle that only boils enough for single cuppa some years ago.(y):)
 

Spectric

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In all these examples you need to include pressure, it has a fundamental input on freezing and boiling points.
 

Cabinetman

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1 We have a plastic kettle because it's light. I bought a similar kettle for my Nan years back and was amazed at the difference in kettle weights available. She could then make tea much more easily. More weight means more material needs heating as well as the water.

2 I bought a new thermos earlier this year, a Thermos Ultimate series. It's the best flask I've ever had. If I leave it in the shed overnight I can still make tea on day two, I'm fussy with tea too. But more to the point, it's supposed to be more energy efficient to fill the kettle totally up then use it from a flask whenever you want a brew. I started doing this a wee bit, and also discovered that you are obviously no longer waiting for the kettle to boil, you just pour the flask and there's your tea. Weirdly satisfying to not be waiting.

3 Also, kind of almost related, I had always thought it was a thing that an upright fridge or freezer was wasteful because the air you had paid to chill falls out every time you open the door. I read someones experiment to see if that was the case and it was so tiny as to not be bothering with. They calculated, for comparison, after a warm or hot bath do you pull the plug? You would save many times more money than the fridge loses by leaving the water in the bath when you have finished until it had given up it's excess heat to the house then drain it, or you are paying to heat your drains! You do get more condensation though.
Interesting about the fridge, I’ve always wondered. Do you not find you get a strange taste to your tea using a flask?
There is a lot on the Internet about not having a plastic kettle – it not being at all good for you (BPA). Leave you to look it up. Ian
 

John Brown

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Just like I've always questioned the reasoning of replacing old style incandescent bulbs with low energy types. The CH just has to wo
rk harder.
We currently pay 20p for a kWh of electricity. 3.41p for the equivalent in gas. There's no way I'm replacing all the LED lighting with incandescent, in the vain hope of saving money on heating bills...
 

nickds1

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We fill our kettle from the hot tap which is at a steady 50C (from the GSHP). It's drinking water and is going to get boiled anyway, plus we only fill the kettle with what is needed.

I've no idea why more folk don't fill from the hot tap? 50% (*) of the work has already been done. Solar tea, anyone?

(*) I know that's not quite right before the physics police get hold of this post. I just can't be bothered to do the maths right now!
 
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Ozi

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I think someone should do the sums. Not me though. I've done enough sums today.

I reckon the water comes out of the tap at 5-10°C. Room temperature is for the sake of argument 20°C, and let's say the kettle takes it all the way to 100°C. If anyone can remember the SHC of water and knows the power output of a typical kettle...
4.2 kJ/kg.K but I'm to bored to work it out


oh hell here goes

The tap water if straight from the mains will be about 8°
100 - 8 = 92

92 x 0.5 x 4.2 = 193.2 kJ to boil half a liter

from 20°

80 x 0.5 x 4.2 = 168 kJ

should save about 13% BUT some of the water was probably in the pipe inside the house unless you run the tap till it's cold' I'm guessing that's the reason or using a tap fed from a tank not direct from the mains
 

Ozi

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Does anyone else make tea in the micro wave. Not all the time you understand because that would be odd but I think it tastes better, don't nuke the tea just the water and be careful when you add it as it can over boil. I believe boiling the water in the kettle reduces the oxygen content and that effects the taste.

Why are so many of the people I meet sleep deprived?
 

John Brown

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We currently pay 20p for a kWh of electricity. 3.41p for the equivalent in gas. There's no way I'm replacing all the LED lighting with incandescent, in the vain hope of saving money on heating bills...
On these tariffs, we would need an air or ground source heat pump to have a COP of nearly 6 to break even on heating costs. Since they seem to average out at almost 3 over the year, from what I've read, our heating bills will double. Much as I'd like to be greener, doubled heating bills are not much of an incentive.
Maybe there's a mistake in my figgering?
 

Woodchips2

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your a teeny weeny wood elf aren't you! My mug holds 900ml on its own and I have around 8 mugs a day of tea not coming round yours bob for a cuppa, I'd die of thirst
Wow Droogs that is one big mug and to drink 8 mugs a day is awesome! I'm guessing you're the Scottish tea drinking champion :cool:
Regards Keith
 

Spectric

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I've no idea why more folk don't fill from the hot tap?
Probably because not everyone has a hot water system that is classed as potable, many used to have open header tanks in the loft that would contain dust and dead insects, etc etc and if you have ever replaced one of these you often found there is a lot of sludge at the bottom.
 

Vann

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...I've no idea why more folk don't fill from the hot tap?...
Obviously every tap is different but, I experimented with one hot water tap in our house that took ages to warm. I measured 7 pints before the flowing water changed from cold to warm. That means every time the hot tap was turned off 7 pints of hot water was left in the pipes to cool off. Wasted heat!

Also, when I was young and impressionable, my BIL (an Englishman, and therefore a tea expert) taught me to always use cold water to fill the jug as it effects the taste.

Cheers, Vann.
 

John Brown

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Obviously every tap is different but, I experimented with one hot water tap in our house that took ages to warm. I measured 7 pints before the flowing water changed from cold to warm. That means every time the hot tap was turned off 7 pints of hot water was left in the pipes to cool off. Wasted heat!
Which is, I believe, why washing machines and dishwashers only have cold feeds these days.
 

Terrytpot

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My wife’s contribution to saving energy is to ensure that the glade plug in air freshener she bought is first of all plugged into a timer so that it can only operate inside a 30 minute window early in the morning…no sense in it working more than once a day apparently 🤣
 
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