Power consumption help needed

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mikeg
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Power consumption help needed

Post by mikeg »

I am currently thinking about replacing my existing fridge with a Samsung 400ltr inverter model and need a little help in understanding it's power usage. The specs list power usage as (kWh/yr)349, how do I convert that figure to daily power usage?
Peter and Sandra
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Re: Power consumption help needed

Post by Peter and Sandra »

349 kWh divided by 365 days in a year gives .956 kWh per day which means it will use 956 watts a day.
Oka 4WD camper/motorhome, 1100w solar, 400ah lithium, diesel heating, HWS and cooking
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Jon and Kay
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Re: Power consumption help needed

Post by Jon and Kay »

Then it depends on battery voltage and inverter losses.
So for a Lithium user at say 13.2v 956/13.2 and add 10% loss through inverter so 956/13.2*1.1=80Ah per day
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mikeg
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Re: Power consumption help needed

Post by mikeg »

Thanks for that so 80 amps per day looks about right then.
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BruceS
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Re: Power consumption help needed

Post by BruceS »

I'd think it would be a bit more than that in real life. Hot weather with grandkids going for drinks & ice etc etc
There is no way those testing the fridge can tell if you are going to be in Tassie or Darwin?
I reckon my 265lt one would be around the 75/80 average. Obviously less in winter & more in summer.
400lt is a good size! In house or MH?

PS. my fridge is listed as 269 Kwh per year.
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T1 Terry
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Re: Power consumption help needed

Post by T1 Terry »

The star rating and kWh per yr is part of a very tough Aust Standard and there is no way to trick it that hasn't been tried and caught out. A few yrs back one mob wrote a special section in the program to sense when in Aust Standards test mode and reduced the compressor cycling allowing a greater fluctuation in freezer and fridge temps. They got caught and fined mega $$ and the test now includes internal temp sensing throughout the loaded fridge that would pick up such changes to the operating system. Just to get to the star rating section requires passing a test no 3 way or 12v fridge could achieve.
Choice regularly conducts tests to try and catch out cheats and that was how the manufacturer got caught out. If those figures were not representative of real world energy use Choice would have called them out by now. The test to be accepted before the star rating test is carried out in a heat soaked 42*C I think it was, the parcels that represent a loaded fridge and freezer are also heat soaked to ensure the 42*C is registered evenly throughout the cores of the test load. They have 15 hrs to get the freezer test load core temp below -15*C and the fridge below 5*C and there must be no part of the load that rises above these temp and it must even throughout. That is a tough call while in an environment of 42*C

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Jon and Kay
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Re: Power consumption help needed

Post by Jon and Kay »

My 240 litre 'standard' Westinghouse runs at 70ah per day.
My 110 litre freezer runs at about the same 70ah per day.

I would have preferred an inverter fridge , but couldn't get one at the time with a LHS door. Now I don't know how I could survive with a smaller freezer :)

The startup current doesn't bother my full time inverter, but an inverter fridge would use less power.
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mikeg
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Re: Power consumption help needed

Post by mikeg »

BruceS wrote: Fri Nov 03, 2017 10:01 am 400lt is a good size! In house or MH?
The new one I am considering will replace my existing fridge in Gypsy Belle which is a 365ltr domestic one I had converted with a Danfoss compressor about 16 or so years ago. There is really nothing wrong with the one I have and there does not seem to be much of a power advantage but the big attraction is the auto defrost, maybe a little more room and possibly a little quieter in operation.
BallaratBill
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Re: Power consumption help needed

Post by BallaratBill »

Hey Jon.... your "roll-around" chair looks good but I'd like a coupla cushions when I visit!

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