Full size to mini fridge experiment
 

After reading about freezer to fridge conversions like this one :
Man Retrofits Freezer to Make an Ultra-Efficient Fridge : TreeHugger
, I wanted to do something similar.
I have a small 3.1 cubic foot mini fridge that I did a few experiments on ( see the post entitled "Turn my frig on its side ?" )
That amounted to nothing, but I did manage to get the power consumption down to less than 200 kWh per year. The main factor which contributed to this was simply turning the temperature dial up as high as it will go.
Food that spoiled easily went bad a few days earlier than usual, but otherwise, all was normal. I kept the freezer section and my ice cream even stayed frozen ( yet soft ).
:cool: Now .....
Recently, I moved into a new apartment that has a normal sized ( 14.5 ? ) cubic foot refrigerator.
As an experiment, I decided to see if I could use just the freezer section of the fridge and use a temperature switch overide to control it.
I purchased a temperature switch from a DIY beer store. It is a simple matter of plugging the cord in, and inserting the temperature probe ito the fridge.
Right off, I'll admit that at my setting of 42 degrees, any frozen items turn to mush - so having ice cream in my fridge is no longer an option ( it melts within a few hours ) I could always dail the temperature down a few notches to where the ice cream doesn't melt, but I don't eat it too often anyways.
Also, frozen veggies thaw out ... which is actually O.K. for me, since they seem to cook faster.
So you are thinking " What kind of frikin moron wants to make their fridge smaller, and loose their freezer ??
Well ... yah, you're right it is pretty lame.
But it is just an experiment.

And the results ? I am currently averaging 143 kWh per year.
( The refrigerator is rated at 497 kWh )

143 kWh is a far cry from the 36.5 kWh that the fellow in the chest freezer conversion got, but he also started with a super efficient low wattage chest freezer rated at something like 170 kWh. I haven't found the freezer he used for under $ 1000.

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The former refrigerator section stays around 70 degrees or less, and I store my breads and nuts there.

Interesting. Did you just insert the temperature probe through the front door?

Yes.:)
Look in the picture above - just below the purple carton, you can see the wire. No other modifications were done what-so-ever.
To the uninitiated, it looks totally normal.

I plan to create some sort of spring loaded air trough around 3" high that can keep the cold air in when I open the door. ( I notice that when the fridge is full of food, a lot less air rushes out. It acts a barrier. )

I'm skittering around in dangerous territory or sorts. I checked the internal temperature of the fridge, and it it currently at 55 degrees.
I'm going to turn it down some, but I must admit that I am curious to see how low that I can go with the kWh readings.

I think a normal fridge is usually set at 40 degrees, and I hope I don't find that any of my food begins to spoil ( and give me salmonella ) :eek:

I purchased a few bags of frozen veggies, and as they thaw, they seem to be helping the fridge stay cool even more. I can see the power curve as they gradually warm. Yesterday, the fridge only used .05 Wh at the 5 hour 36 minute mark. ( It turned on twice in that time. )
At the 8:15 mark the reading was .06 Wh.
Currently the reading is .13 Wh and its been over 11 hours.

This can be a good excuse for me to eat more frozen veggies . :thumbup:
Just pop a bag or two of the veggies in there every couple of days.

Lol at the veggie idea. But, it would work!

40 degrees is a high temp for a fridge. I think the highest I can set mine is 45.

If you know how, also unplug the defrost circuits.

( I was wondering if this could be done, but was told that it is not possible. :( )

I would think there has to be a way. Its just a resistive heating element, right? Snipe the right wire (or find a connector) and you should be done.

Some higher efficiency models actually used a reversing valve for defrost. Most use a ceramic heater. In either case, the easiest way to disable the defrost is to find the defrost controller (usually just a simple timer), then remove it and jumper the connections for normal operation.

Overall, I must say that this experiment is a sucess for me. Here is my current electric bill. :)

My new apartment is twice the size of my old one, yet I am using less energy.
The apartment is very well insulated, and I barely have to use the air conditioner despite the fact that we are in a drought with several weeks of 95* to 112* temperatures.
I use a low wattage fan ( 7 Watts ) in place of the A/C unless I become uncomfortable.
Currently it is 77* in my apartment, but I'm quite comfortable with my fan.
I also use CFL lighting, and only when there is not enough light to see from the open blinds. I cook using a sandwich maker versus a stove to make the best use the heat.

I take it to the "extreme", and I just wanted to add this as sort of a disclaimer that this low of an electric bill is not purely the result of doing this fridge modification.
It certainly helps though. The lady at the power company said there was a huge dip in my power meter when I did this modification.

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