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Formula for calculating electricity requirement?

Featured Replies

I mentioned in a thread a while ago that i had a fair bit of external temperature and humidity data for my site.  (I've got external temperature, humidity and pressure recorded at minute intervals for many years)

 

I've been playing with sap figures trying to decide which insulation to opt for and would like to take sap numbers and try to get some annual electricity figures for GSHP/ASHP etc.

Sap W/C x delta C / CoP for heating duration seems very simplistic and won't take into account the internal temperature change as the building heats up. Not sure if i'm overthinking this.

 

Any pointers to reading greatly appreciated.

 

@JSHarris has produced a spreadsheet to model heat loss from a building and I can certainly say it gives accurate answers.  you input your house details, wall and window U values and it tells you things like KW of heat loss at different temperatures.

 

It accurately predicted the heat loss from my house when it is +20 inside and -10 outside is a shade over 2KW

 

I am sure someone will be along with a link to download it.

27 minutes ago, ProDave said:

It accurately predicted the heat loss from my house when it is +20 inside and -30 outside is a shade over 2KW

 

 

-30 ? ?

17 minutes ago, epsilonGreedy said:

 

-30 ? ?

Typo corrected.  I meant -10, with 30 degree difference between in and out.

 

Though one night this winter it did get to -15

  • Author
21 hours ago, ProDave said:

@JSHarris has produced a spreadsheet to model heat loss from a building and I can certainly say it gives accurate answers.  you input your house details, wall and window U values and it tells you things like KW of heat loss at different temperatures.

 

Thanks for that. I've downloaded it.

?

  • 4 months later...
On 26/06/2019 at 15:55, Digmixfill said:

 

Thanks for that. I've downloaded it.

?

 

Hi, do you have a link to this spreadsheet? I'm struggling to search for it.

  • 2 weeks later...
  • Author
On 01/11/2019 at 09:32, ma9mwah said:

 

Hi, do you have a link to this spreadsheet? I'm struggling to search for it.

Glad to see someone sorted out your request :)

The site seems unable to send me notifications of replies and I've only just seen this :(

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