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Offline syhprum

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Coffee brewing problem
« on: 12/01/2009 21:30:04 »
When I prepare my morning coffee I require one liter of water at 100C, I can obtain this in two ways I either fill the kettle from the cold tap at 10C or I runoff three liters of water from the hot tap until it runs at 50C and then fill the kettle from this.
Assuming the water in the hot tap has been heated from 10C and as the cost of gas for heating the hot water is 25% per Kwh compared to the electricity which is the most economical?


 

lyner

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Coffee brewing problem
« Reply #1 on: 12/01/2009 21:47:15 »
You drink too much coffee, anyway, syphrum.
 

Offline RD

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Coffee brewing problem
« Reply #2 on: 12/01/2009 22:27:42 »
If the hot tap water comes from a copper tank it will have an increased amount of copper salts in it compared to the cold tap water. The copper salts may taint the taste of your coffee.

[The cold water is delivered in copper pipes but because it is cold less copper salts will be dissolved in it than in the hot water]
« Last Edit: 12/01/2009 22:29:25 by RD »
 

Offline DoctorBeaver

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Coffee brewing problem
« Reply #3 on: 12/01/2009 22:39:12 »
Oh tut! You should never use boiling water for coffee. Use water slightly off the boil to bring out the full flavour.
 

Offline dentstudent

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Coffee brewing problem
« Reply #4 on: 13/01/2009 08:03:24 »
Go and buy a nice bean-to-cup machine, and all your coffee worries will be over. I did, and mine are!
 

Offline syhprum

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Coffee brewing problem
« Reply #5 on: 13/01/2009 08:20:52 »
I did not cook the figures but merely took typical ones but when I did the arithmetic I found the cost of either procedure to be the same.
I know of course water needs to be 95C but not having a thermostatically controlled kettle it is easier to heat it to 100C and then add a little cold.
 

The Naked Scientists Forum

Coffee brewing problem
« Reply #5 on: 13/01/2009 08:20:52 »

 

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