Off grid refrigeration

[Oregonian]

I am brand new here, and do not have any solar, nor off grid equipment yet. I am unhappy with the P.U.D., and desire to "cut the cord". I expect it to cost money, but I am a little bit bull headed, and I want to be off the grid. I live in Oregon, and have excellent southern exposure, with plenty of room for a solar array. I think my main needs from battery power will be refrigeration, lighting, and electronic entertainment (computer, tv, cell phone).

I am trying to cram info into my brain, but it is taking more time and effort than I expected. My first question is how to provide myself with refrigerator and freezer without the grid. I see a couple brands of appliances designed for off grid, which run on DC, but I also see that I could use an inverter and keep the same appliances I already have. Is there a good reason to purchase the purpose built off grid appliances (refrigerator, and freezer) ? I do have a great generator to use as back up, and for occasional large loads like laundry. I will be looking into propane tankless water heater, and propane off grid range/oven to back up a wood cookstove. I am in a "modern" on grid home with wood and electric heat, so I can make the transition in steps.

Thank you for your time and patience.

 

[Craig]

No need for expensive DC appliances. I use a chest freezer that is disconnected at night. Stuff still stays frozen easily. I do throw in 4 gallons of water to freeze to help keep thermal mass but if freezer was full it wouldn't be needed. For refrigeration I use a chest freezer as well but have a thermostat so it does not freeze. But this summer I am thinking a normal refrigerator vwilk be fine. Maybe keep any extra space stocked with water again for thermal mass. Instant propane water heaters work perfect for off grid. After that change all lights to led and you will be on your way. Try to do all phone/laptop charging during daylight to save on needed battery capacity.

 

[mapguy525]

Conversion factor costs. Each time you convert voltage -you have loses. Basically, refrigeration will fall in to 3 categories - absorption, compressor, and or icebox.

 

[Craig]

Conversion factor costs. Each time you convert voltage -you have loses. Basically, refrigeration will fall in to 3 categories - absorption, compressor, and or icebox.

Yes there are losses but for the price difference you can add probably 1000 watts of panels or more. that will way surpass any loses.

 

[Craig]

I used to be totally worried about conversion losses do not get me wrong but living with the stuff in the real world for 3 years (all be it part time) I have come to realize they really are not that bad and can easily be overcome with more panels and more battery. Consider $300.00 for a standard freezer or $1200 or more for a DC freezer. I can get panels for $.33 per watt so that $900.00 can get me 2500 watts of panels or more. But of course there is added cost in larger SCC and what have you that's why I said about 1000 watts above.

 

[Oregonian]

Yes there are losses but for the price difference you can add probably 1000 watts of panels or more. that will way surpass any loses.

Are you saying for the expense of buying the DC appliances, it would be better to just add to the solar/battery system ?

 

[mapguy525]

Understand, just putting the options out there. Each situation and budget is different.

 

[Craig]

Are you saying for the expense of buying the DC appliances, it would be better to just add to the solar/battery system ?

Yes but more like fir the same extra expense of the DC appliances you can use that money to make a better larger system

 

[Craig]

Understand, just putting the options out there. Each situation and budget is different.

Yes especially in a van or Mobile situation the DC may be better

 

[namesgolden]

I agree, for people without size limits its just better to vastly oversize your system. gives you the flexibility to run unexpected large loads like saws and microwaves-- if budget allows you could even build big enough to run a mini-split for heat pump/ac/dehumidification.

even RV'ers are ditching their LP/ac fridges and going to home style fridges. some can be very efficient.

a converted chest freezer can be a crazy efficient fridge -- doubly so if you make the bottom layer jugs of water. you'd still want a regular fridge in the kitchen though.

my wife worked in high-end restaurant kitchens and ran kitchens for festivals/remote work sites for years. I intend on building out plenty of food storage for her.

 

[Oregonian]

I agree, for people without size limits its just better to vastly oversize your system. gives you the flexibility to run unexpected large loads like saws and microwaves-- if budget allows you could even build big enough to run a mini-split for heat pump/ac/dehumidification.

even RV'ers are ditching their LP/ac fridges and going to home style fridges. some can be very efficient.

a converted chest freezer can be a crazy efficient fridge -- doubly so if you make the bottom layer jugs of water. you'd still want a regular fridge in the kitchen though.

my wife worked in high-end restaurant kitchens and ran kitchens for festivals/remote work sites for years. I intend on building out plenty of food storage for her.

I think I seen something about freezers used as refrigerators, building up moisture inside ? Is that a real problem ?

 

[namesgolden]

I think I seen something about freezers used as refrigerators, building up moisture inside ? Is that a real problem ?

I haven't read that. I don't have one, but if I did it would be to store packaged bulk items -- keeping veggies and such in a regular fridge.

 

[Craig]

I think I seen something about freezers used as refrigerators, building up moisture inside ? Is that a real problem ?

I have not noticed it but we clean often. I think for a fridge a normal one is fine you just need to be mindful of its power usage.

 

[Dzl]

I think I seen something about freezers used as refrigerators, building up moisture inside ? Is that a real problem ?

I haven't heard that, but I haven't heard much..
I'm not sure why they would (more than a normal refrigerator), its the same technology isn't it (fridge or freezer)?

 

[mapguy525]

Residential refers put heat load into the room where they operate. For RV's/mobile environments in warm climates this can be an issue.

My point is that analysis of major consumers needs be done in a way that accounts for the full operational footprint involved for the device -not just the impact of the ah used and storage of the ah needed for the autonomy required.

 

[Bleedingblue]

Im basically off grid and run my whole house sans the 4.5 ton heat/air unit.

I have a 26 cuft deep frreze and a 15 cuft deep freeze and fridge. Plus the well, a few tvs big stereo etc. I also have a instant propane water heater and gas dryer and stove. Dish washer is electric.

Im on a 48 volt system and only have 12-335 watt panels. Problem us when its cloudy which can happen here for days.
Now im using 24 trojan L16 batteries in 3 strings of 8. Wish i had double or triple the panels and double the battery capacity.
I do major electric usage on days where their is plenty of sun like using the dishwasher or using electric appliances. If using the well for a couple hrs will run the batteries down even if it is sunny as the well uses a ton of power.

 

[Roc off-grid in Quebec]

No need for expensive DC appliances. I use a chest freezer that is disconnected at night. Stuff still stays frozen easily. I do throw in 4 gallons of water to freeze to help keep thermal mass but if freezer was full it wouldn't be needed. For refrigeration I use a chest freezer as well but have a thermostat so it does not freeze.

How do you find using a chest freezer as a fridge? I’ve been reading up on this and it sounds like it could save a lot of electricity but am not sure it’s really worthwhile. I’m debating the size that’s similar to a bar fridge - 3.4 cubic feet. I’m not sure the hassle is worth it.

 

[Craig]

It works fine but I agree the hastle probably isn't worth it. Plus in the summer when the refer uses most energy there is plenty of sun and in the winter the refer uses less energy. That isxwhy this year I will try a small fridge with lots of water,soda, and adult beverages to help with thermal mass.

 

[Roc off-grid in Quebec]

Thanks ?

 

[Guda]

Thermal mass is key. I bought a chest freezer & put 6x 1gal jugs of water in the bottom & I could not get them frozen with the power I have. So I bought $60 worth of ice & "kick started" it. Now I rotate 2 of those jugs into a cooler daily & thats my fridge. As I get more frozen food I try to give the ice to my neighbors.

I really like the top of the freezer for food prep. I plan on getting a 2nd one & converting it to a fridge. Then both will be counter tops in my kitchen. I'll probably put drawers under them to raze them some. Other than that I really like the way they work.