# Excel formula for heating household water

#### pedruid

##### Expert Member
:erm: Anyone got a spreadsheet for this that they are prepared to share.

##### Honorary Master
If your water is edible you have bigger problems than excel

#### Arzy

##### Honorary Master
If your water is edible you have bigger problems than excel
Get it right, he misspelled, he wants to heat his water using excel.

#### spiff

##### Expert Member
:erm: Anyone got a spreadsheet for this that they are prepared to share.
Can give you the formulae for the specific heat capacity of water but not in excel format.

#### McT

##### The Humble Scot!
If your water is edible you have bigger problems than excel
The grammar Nazi in me also cringed.

@OP, hope you come right.

##### Honorary Master
Get it right, he misspelled, he wants to heat his water using excel.
Overclocked cpu and some huge pivot tables?

#### pedruid

##### Expert Member
Can give you the formulae for the specific heat capacity of water but not in excel format.
thank you. It would be very helpful and I could create my own spreadsheet.

#### Ho3n3r

##### Honorary Master
I hate to break it to you, but you need a kettle or a geyser to do that, not a spreadsheet...

#### spiff

##### Expert Member
thank you. It would be very helpful and I could create my own spreadsheet.
No problem.

I'll dig out my applied science book tomorrow.

#### maumau

##### Honorary Master
I think eating = using not heating?

#### KT-B

##### Honorary Master
The internet gives this:

Analysis:
Coal releases heat.
Ice gains heat and undergo change of state. So heat gained is used to raise temperature of ice from -10oC to 0oC, to undergo change of state from ice to water as well as to raise temperature of water from 0oC to final temperature.

Working:
Let final temperature be θ.
heat lost by coal = heat gained by ice + heat gained to change state + heat gained by water
mc cc ∆θc = mi ci ∆θi + m lf + mw cw ∆θw
0.05 * 710 * (200 – θ) = 0.01 * 2100 * (0 – (-10)) + 0.01 * 336000 + 0.01 * 4200 * (θ-0)
θ = 46.1oC

#### KT-B

##### Honorary Master
Or

Using the formula Pt = (4.2 × L × T ) ÷ 3600 you can calculate the time it takes to heat a specific quantity of water from one temperature to another temperature.

Calculate the kilowatt-hours (kWh) required to heat the water using the following formula: Pt = (4.2 × L × T ) ÷ 3600. Pt is the power used to heat the water, in kWh. L is the number of liters of water that is being heated and T is the difference in temperature from what you started with, listed in degrees Celsius.

Substitute in the appropriate numbers into the equation. So imagine you are heating 20 liters of water from 20 degrees to 100 degrees. Your formula would then look like this: Pt = (4.2 × 20 × (100-20)) ÷ 3600, or Pt = 1.867

Calculate the amount of time it takes to heat the water by dividing the power used to heat the water, which was determined to be 1.867 with the heater element rating, listed in kW. So if your heater element rating was 3.6 kW, your equation would look like this: heating time = 1.867 ÷ 3.6, or heating time =0.52 hours. Therefore, it would take 0.52 hours to heat 20 liters of water, with an element with a rating of 3.6 kW.

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#### Neoprod

##### Honorary Master
lol, the snark is strong with this one.

#### KT-B

##### Honorary Master
Had to give rep - you asked for formulas - I gave you formulas.

But look at the other post

#### pedruid

##### Expert Member
:crylaugh: You don't know how cold and hungry I am.

#### saor

##### Honorary Master
:crylaugh: You don't know how cold and hungry I am.
Are you the person without electricity for the last few weeks?

#### agentrfr

##### Expert Member
Here you go buddy

Code:
``https://mega.nz/#!SkUUTSRC!UF0NjojY7uRZR0BRt64_p9MXq4Eb60tHlcafLZQRh2Y``