Unplugging the Frezzer

[efficientPV]

The OP said fridge and freezer turning off at night. My chest fridge goes from 33 to 40 in the morning (upper section). If you go out and buy a bunch of groceries/ drinks late in the day and then turn off the fridge a couple hours later, you'll be in trouble.

So, you are saying the fridge only consumes 100WH in a 24hr period if left on and 300WH if turned off at night. 100WH seems exceedingly low. I certainly don't believe it. Did you let the freezer stabilize a couple days between tests?

 

[Dzl]

So, you are saying the fridge only consumes 100WH in a 24hr period if left on and 300WH if turned off at night. 100WH seems exceedingly low. I certainly don't believe it. Did you let the freezer stabilize a couple days between tests?

You may have misread the OP

I found that leaving them plugged in they pulled from 1.8-2kwh and unplugging it they pulled 3kwh. Has anyone else seen this or even tested it?

That works out to 75-83 Wh/hr (plugged in 24/7 and 125 Wh/hr (unplugged at night) if I understand correctly.

 

[Deleted member 1888]

I did not have it full to the brim so maybe that is one factor I don't know.

 

[tricky74]

Switching off overnight probably suits a fairly full fridge / freezer that does not get opened after dark often.
And on a way undersized battery storage setup with zero days autonomy.
But with plenty of solar.
Overall power consumption increases but battery storage requirement decreases.
I may do this at my bbq area with a small beer fridge.
And you use a timer to do it automatically.

 

[efficientPV]

Seeing and believing are often both wrong. FOW

I've been in measurement my whole career and testing methodology can skew results a lot. I'd like to see data from a five day test. You may not be dealing with the same average temperature in a short period. Heat loss should be about the same. Compressors take a lot of surge current each time they start and higher current for the first 4 minutes. Letting it run longer in the morning after a night off should save some power. Something is happening. It just might not be what you expect.

I only run in the day and have no way to run at night. It is all about having a smaller battery bank anyway.

 

[PHoganDive]

Another variable is the defrost cycle which uses a heating element. Unplugging prevents the defrost cycle which should save power.

My Fridge nameplate is 11.6A however my kill-a-watt measures around one amp when running. I have yet to monitor power during the defrost cycle.

I think you'll find the defrost heaters use the lions share of that for the brief time they're on. When it does a defrost cycle, it wants to QUICKLY heat the cold surfaces to melt any frost that has formed on them, but not thaw food in the freezer, so it typically has a high powered heaters to melt the frost quickly, then shut off before any food thaws. A low powered heater that takes 3 hours to melt frost would thaw food as well, a high powered one that completes it's task in 10-15 minutes won't.