.25 kwh/day Refeigerator

MEMPHIS91 · 09-20-15, 04:44 PM

Howdy guys, so I was looking for a way to power the fridge solar powered. I put a meter on my existing fridge and it read 2.8kwh in one day. Though that is doable I needed it to fit the solar system I already have (800 watt) and I needed it to pull zero stand-by power from my inverter.

I found tons of info and youtube videos on using a chest freezer so that is what I did. 11 cu foot Frigidaire chest freezer was ordered and arrived in one week. I had to order it because I could not find a good size for the place my old fridge was. But with free shipping, who cares.

To do the zero stand-by power, I decided to power a thermostat on 12v from my battery bank. zero stand-by is important so that my inverter can go to sleep and save me power at night. I ordered this beauty, http://www.amazon.com/gp/product/B00...ilpage_o00_s00 same one as from the heat pump food dryer build but this one is 12v and can be either C or F.

I wired the 12v power in the thermostat, looped the senor mid way into the chest freezer, and wired the compressor to the relay. SIMPLE.
I set the thermostat to on at 39F off at 36F.
The meter said I used .25kwh in a day!

Now I did loose a freezer, but I only needed a little one so I found a cheap 7 cu foot one that only uses .4kwh a day. So total would be .65kwh compared to 2.8kwh. May not seem like that big a difference. But knowing my fridge stays on even when the power is out is totally worth it. Plus every time I open the fridge I don't loose a lot of my cold air since cold air is heavy it stays in. I have also heard reports that the food stays fresher because the it stays more consistent.

Ideas to improve.
-Exterior condenser wrapped around the hot water heater tank? Thinking about 20 feet of 1/4" should do it.
-Replacing the R134a with R290/R600a, or just adding a little R290 to the R134a.
-Adding a layer of ice packs (the blue hard ones) on the bottom to add some mass to the load. Hopefully to retain the cold for longer periods of time.

Thanks for reading,
Enjoy.

09-20-15, 04:44 PM	#1
MEMPHIS91 Journeyman EcoRenovator Join Date: Apr 2015 Location: Oxford, MS USA Posts: 496 Thanks: 69 Thanked 87 Times in 61 Posts	.25 kwh/day Refeigerator Howdy guys, so I was looking for a way to power the fridge solar powered. I put a meter on my existing fridge and it read 2.8kwh in one day. Though that is doable I needed it to fit the solar system I already have (800 watt) and I needed it to pull zero stand-by power from my inverter. I found tons of info and youtube videos on using a chest freezer so that is what I did. 11 cu foot Frigidaire chest freezer was ordered and arrived in one week. I had to order it because I could not find a good size for the place my old fridge was. But with free shipping, who cares. To do the zero stand-by power, I decided to power a thermostat on 12v from my battery bank. zero stand-by is important so that my inverter can go to sleep and save me power at night. I ordered this beauty, http://www.amazon.com/gp/product/B00...ilpage_o00_s00 same one as from the heat pump food dryer build but this one is 12v and can be either C or F. I wired the 12v power in the thermostat, looped the senor mid way into the chest freezer, and wired the compressor to the relay. SIMPLE. I set the thermostat to on at 39F off at 36F. The meter said I used .25kwh in a day! Now I did loose a freezer, but I only needed a little one so I found a cheap 7 cu foot one that only uses .4kwh a day. So total would be .65kwh compared to 2.8kwh. May not seem like that big a difference. But knowing my fridge stays on even when the power is out is totally worth it. Plus every time I open the fridge I don't loose a lot of my cold air since cold air is heavy it stays in. I have also heard reports that the food stays fresher because the it stays more consistent. Ideas to improve. -Exterior condenser wrapped around the hot water heater tank? Thinking about 20 feet of 1/4" should do it. -Replacing the R134a with R290/R600a, or just adding a little R290 to the R134a. -Adding a layer of ice packs (the blue hard ones) on the bottom to add some mass to the load. Hopefully to retain the cold for longer periods of time. Thanks for reading, Enjoy. Attached Thumbnails