# Solar VS Fridge

Discussion in 'Renewable Energy' started by ardollo, Jun 18, 2012.

1. ### ardolloNew Member

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Hi All
I have a remote solar system delivering true sine wave 240v to a fridge running non stop ie 24hours (long story) The system currently copes with the existing fridge running at 2.8 amps consistently around the clock.
Trying to ensure that a new fridge will not use more energy and have figures on new fridges like 350kwh/year?
Can anyone tell me how to calculate a comparison between the existing 240v x 2.2amps x 24hrs x 365 days energy use and the new fridge claimed 350kwh/year?

2. ### strantorActive Member

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?
you just typed it.
240v x 2.2amps x 24hrs x 365 days
240V * 2.2A = 528W
528W * 24hrs = 12.672KWH/day
12.672KWH/day * 365 = 4,625.28KWH/yr

at the rate I pay (11c/KWH) that's 508\$/yr
with your new fridge I would pay 39\$/yr

Last edited: Jun 18, 2012
3. ### ardolloNew Member

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Thank's from Down Under Strantor

I did that calc but find it hard to believe, you know when you get that feeling that you are missing something
Much appreciated

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5. ### strantorActive Member

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2.2A @ 240v is a lot to be running continuously. (don't worry, I won't ask)

6. ### RCinFLAWell-Known Member

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A refrig compressor running 24/7probably won't last very long. Try closing the door on the refrig.

13 kWH of solar power is a pretty large array. Are you really sure the compressor is continuously running or are you just leaving the power on 24/7.

A sinewave inverter capable of starting the compressor has to be in the 1000 watt or larger size. You would have an inverter overhead of about 35 to 50 watts just to run the inverter without any load. Just that inverter overhead (about 900 WH's for 24 hrs) would just about double the power used over just the AC power of the refrig.

Typical recent design refrig in 17 cu-ft range should consume a little less then 1 kWH per day in typical use case. This is inline with the 350 kWH/year energy sticker. If you have a bunch of kids that stand in front of the open door refrig for several minutes each time the door is open this number will be much higher. If you put it out in a hot garage the number will be larger also.