Solar Refrigerator Power Supply

Hi Wood Gassers,

This is a page that I have been wanting to do for a while.

It’s raining outside so I am stuck doing indoor stuff and my “Honey do” list.

Bill S and I talked about sizing a solar system for his new place and this is a decent start toward what I would consider as an absolute minimum.



Stephen, I run a chest sized refrigerator off a 75 watt panel on the roof of my shell on my truck. It requires no inverter. In my office I run a dorm type refrigerator off the inverter there. Most of my web sites are gone now but I think those pictures are still up … Mike links below seem to work still …

Stephen, Too much reading for me but I just wanted to comment that old UPS units generally make good inverters. Modified sine wave inverters are not good for much except for running ac’dc motor drills and saws … Computer UPS units usually put out something closer to a sine wave. Problem with modified sine wave inverters is if the motor (compressor) you plan to run starts in the wrong phase (one in ten times) it will set up eddy currents in the windings and force them to draw around 10 times the current. Hard to catch before the motor smokes or the wires melt … Make sure you fuse the fridge at threshold … I had to replace 6 fuses one night on my old tube radio gear … I use pure sine wave inverts most of the time … I want some blueberry jam !!! Let me know when it is ready … Thanks, Mike

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Hi Mike,

I went with a pure sine inverter on the build I did. It worked out well. For the amount you need to spend to build a functional system, I wouldn’t go any other way.

What’s your address? I need to cook blueberry and strawberry-rhubarb in the near future.


Stephen, There is usually plenty of rhubarb here but zero blueberries …I don’t like rhubarb :o) We pick plenty of raspberries and black caps here in June and black berries later in the summer … I just transplanted some red canes around but they won’t produce till next year. The fall crop usually gets frozen. We usually get a pile of wild grapes … Daaaas good … mmmmmmmmmm … Need cheese cloth with them and get purple hands …
My mailing address is
PO Box 383
Linden, WI 53553
for UPS it is 263 E. Main St.
same same …
I’ll reimburse … Thanks, Mike

Watch the mail! :smile:

Thanks Stephen, The grapes are just starting to grow … Walnuts don’t have leaves yet but are getting them … I’ve seen them get froze off 3 times … The nasties t(tornados and hail) may have gone by us … I’m typing on Steve U’s old computer I have to bacvk up and re-type 3 times a sentance … It picks the keys it wants … Casper the friendly ghost … My stupid neighbor filed many complaints with the cops a few weeks ago … Then the cop started to hassle me about my studebaker … I just fired it up ear4lier and have it up here in front of tgh4 trailer house … He can look at it till after Argos … I will not go back to correct spelling … Not my fauly … I type a large part of my days … I’ll post a picture on my blog page if I can find it here … I have to pull the card out of the camera …I think I will do a short soundless video … Mike

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Yep that skipping cursor machine will drive you batty, or too drinking too heavily.
STILL say try a remote keyboard and mouse and use it “hands-off” as just a base unit.
Just had the first of season ruhbarb cobbler. Yum. Yum.

Jeff an alternative to inverters search up RediLine DC to AC rotary converters (motor/genrator). Manufactured 1980’s to current. Used a lot as work basket tools power suppliers on self-travel manlifts. The 1600 watt versions are readily available used E-Bay. These are copper winding’s and laminated iron balls deep for motor starting and have nice clean output for any electronics. On my old DOW photo album I showed my collection of three 1600 watt’ers, two 550 watt’ers and my old heavy as sin Trace 2.5kw modest frequency/heavy transformer full-sine inverter/multi-source charger.

Steve Unruh

This very nice technology to save electricity by solar power.Power supply by solar energy to cool thing in refrigerator. this technology also use for commercial purpose and research work like it is use in solar vaccine refrigerator and basically this fridge use in labs for research.

Based on their posted power comsumption I am guessing it is a peltier junction cooler not a compressor type. It uses a lot of power for very little storage by contrast my energy star complies regular fridge at 21 cubic ft with freezer and defrost only uses 750-850 watts… versus about the same power for a third the volume and no freezer…


Not really 750W. Try this…

It was a bit of an eye opener for me.


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Hey Stephen, good hearing from you. I’ll have to chomp the numbers of the whole post. I do know the numbers on my fridge are correct though as set to setting 3 on the fridge and coldest on the freezer. So it outperforms it’s energy star tag as per a kill a watt plugged in for 2 weeks. I did not account for losses but would it not be fair to say in an off grid house they would be shared over the whole system not just the fridge? I feel like a bit of a poser of course since we are only partially off grid now…
Best regards, David Baillie

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Hi David,

Absolutely the load would be shared over the whole house, but for me cold beer is the critical thing to get right first. :beer:

Groceries might be important too.



Why did you calculate 5 days for the panels at 5.2 kwh then turned around and used that for the daily capacity of the needed solar panels and batteries? Not to mention the conversion to joules is absolutely worthless since everything you are trying to calculate is in watts anyway.