How to calculate the kVA requirement for an uninterrupted power supply aimed to last 24 hours?
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Hi everyone,
I'm frequently back home in India where power outages can become rather bothersome.
I'm basically trying to calculate the kVA requirement for my home using the power calculator here: http://www.su-kam.com/load-chart.aspx
Although I can roughly understand the concept of the load being put on the system, I cannot figure out how long the backup power will last.
Power failures in my city can be as long as a whole day (not 8 hours, but the whole 24 hour shabang). So, I am trying to calculate the kVA needs for:
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1 x 48 inch plasma screen (in reality we have a 55" LED TV)
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1 x 1000W music system
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1 x 480L fridges (this is the critical component in the house that absolutely needs to be powered)
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20 x 22 watt CFL lights
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1 small printer
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1 small scanner
This usually results in 10,000VA - 15,000VA on the website, but what it doesn't say is how long we can keep these items powered on for.
Now, I know most of the time all these equipment will be turned off (except the fridges: food spoils REAL fast in hot and humid places), but it would be nice to know that we can power all this for 24 hours (if need be).
So the base question is, how do I calculate the kVA requirement for all the above items if I want to power them for 24 hours?
Thanks!
EDIT: Based on advice below, I am shifting to only needing to power a single 480L fridge + a ceiling fan + a few CFL lights. I've put my calculation below for people to check whether I am correct in my approach.
EDIT2: Number of fridges now goes to only one.