Best truly efficient off grid fridge/freezer?

softdown

Our fridge is likely to be our largest consumer of power when off grid. So I searched for something "ground breaking" and found an "item of interest." The walls are 3"-5" thick. Runs on 12 or 24 volt DC. Chest configuration so the cold air doesn't fall out every time the door is opened. Only one review to date. States very low energy usage but gave it four stars. Perhaps they were a tad disappointed in the interior space? Insulation occupies a large percentage of the unit. Costs $1300. Weighs 154 pounds. Offers 8 1/2 cu. ft. of storage space.

I'd guess this a good value for a certain niche. Headquarted in Germany and claiming a year 2000 start up date. If I was our host, I'd take a closer look at offering this unit. Their American headquarters are in Tucson, AZ. https://www.phocos.com/na/blog/portfolio/fr240/

https://www.amazon.com/Phocos-FR240MP-DC-Refrigerator-Freezer/dp/B017BXQY2G/ref=sr_1_5?keywords=inverter+refrigerator&qid=1551979607&rnid=2941120011&s=appliances&sr=1-5

Photowhit

They currently sell a highly regarded(in solar circles) Sundanzer 8 cu Ft chest fridge/freezer(fridge or freezer dependent on the thermostat)If you look it up on Amazon, you will find 3 bad reviews I believe 2 out of the 3 are from people using them in a commercial environment. They have double seals and trying to open the doors rapidly stresses both the seals and the hinges, the things people complain about.

https://www.solar-electric.com/sundanzer-dcr225-battery-powered-refrigerator.html

Photowhit

Where are you located? I think Florida, I know where there is one of these in Missouri from someone who used it at their hunting cabin. Reasonably priced. I think I still have the Phone #.

softdown

https://forum.solar-electric.com/discussion/comment/395976#Comment_395976

Very similar unit and price. Oh well.

Dave Angelini

Build your own!

https://forum.solar-electric.com/discussion/comment/62546#Comment_62546

https://forum.solar-electric.com/discussion/comment/62546#Comment_62546

Or use a Stecca with German Engineering.

https://thesolarstore.com/steca-pf166-solar-refrigerator-or-freezer-12v-or-24v-dc-58cf-p-95.html

terracore

A regular chest freezer (not a "frostless" model) converted into a refrigerator uses about 10% the power of an equivalent side-by-side upright fridge.  Modern "frostless" refrigerators use half their energy on the "frostless" feature and actually run a ~600 watt heater during the defrost cycles, which subsequently warm the cooled areas and require more refrigeration energy to keep the food cold. 

So you can skip the expensive DC route and do what most off-griders do and buy a ~$200.00 chest freezer from Home Depot or Lowes or wherever and convert it into a refrigerator with a $30.00 product like this in less than 3 minutes:

https://www.amazon.com/gp/product/B079GWBQVZ/ref=as_li_ss_tl?ie=UTF8&psc=1&linkCode=ll1&tag=cd023-20&linkId=1b5f17aa714d80e96406768da7bd7bf9&language=en_US

To answer the second part of your question about an "off grid freezer", we use a regular chest freezer from Home Depot.  It pulls about 89 watts and we set it at max cold which takes it down to about -8F.  It only runs during the day when the sun is out (we use a regular appliance timer).  It's never been warmer than about 12F when it kicks on again in the morning which is still 20 degrees below freezing.  As long as you keep it full it only has to run a few hours per day to keep everything frozen.  Occasionally if we kill a pig or something and dump a bunch of warm stuff into it, obviously we have to extend the run time if we're putting into the freezer in the evening etc.

You can even get clever and put a jug of water to freeze into the chest freezer in the morning, and then put it into the converted "refrigerator chest freezer" in the evening, and store the sun's power thermally in the form of ice rather than trying to put the power into more expensive batteries.  The frozen jug will help keep the refrigerator cold without using electricity.  Then move the jug to the freezer in the morning when the sun is out, rinse and repeat, etc.

spacebass

Must buy an Inverter fridge freezer I live in Thailand I have a 14.2 cu ft LG inverter fridge freezer I have measured it twice over 24 hours at  1.1 and 1.2 kwh. The defrost cycle wattage is 161 watts.

softdown

terracore said:

A regular chest freezer (not a "frostless" model) converted into a refrigerator uses about 10% the power of an equivalent side-by-side upright fridge.  Modern "frostless" refrigerators use half their energy on the "frostless" feature and actually run a ~600 watt heater during the defrost cycles, which subsequently warm the cooled areas and require more refrigeration energy to keep the food cold. 

So you can skip the expensive DC route and do what most off-griders do and buy a ~$200.00 chest freezer from Home Depot or Lowes or wherever and convert it into a refrigerator with a $30.00 product like this in less than 3 minutes:

https://www.amazon.com/gp/product/B079GWBQVZ/ref=as_li_ss_tl?ie=UTF8&psc=1&linkCode=ll1&tag=cd023-20&linkId=1b5f17aa714d80e96406768da7bd7bf9&language=en_US

To answer the second part of your question about an "off grid freezer", we use a regular chest freezer from Home Depot.  It pulls about 89 watts and we set it at max cold which takes it down to about -8F.  It only runs during the day when the sun is out (we use a regular appliance timer).  It's never been warmer than about 12F when it kicks on again in the morning which is still 20 degrees below freezing.  As long as you keep it full it only has to run a few hours per day to keep everything frozen.  Occasionally if we kill a pig or something and dump a bunch of warm stuff into it, obviously we have to extend the run time if we're putting into the freezer in the evening etc.

You can even get clever and put a jug of water to freeze into the chest freezer in the morning, and then put it into the converted "refrigerator chest freezer" in the evening, and store the sun's power thermally in the form of ice rather than trying to put the power into more expensive batteries.  The frozen jug will help keep the refrigerator cold without using electricity.  Then move the jug to the freezer in the morning when the sun is out, rinse and repeat, etc.

I would absolutely do that if strapped for battery power. Batteries are good and I am still quite tempted. Put the Kill-a-watt meter on my large chest freezer - it does very, very good compared to the fridge. I like to give it a week or so - then I will post results if I remember. 

Seems you would get a lot of frost on your food fluctuating from -8F to 8F on a daily basis. 

softdown

Hopefully the defrost cycle would never turn on when the freezer is being run over 32F. 

It wouldn't surprise me if more high end fridge/freezers had more active defrost cycles and consumed more energy as a result. People that buy high end fridges are likely not too worried about defrost cycle energy usage - they want pretty food. 

BB.

Neil, a former moderator here did a test on a fridge/freezer with a kWH meter--And after disabling the defrost cycle, found that after ~24 hours, the evaporator started to freeze up and average daily energy consumption started to increase.

-Bill

706jim

Back when solar panels cost more than $5/watt, the power consumption of an electric fridge made them impractical for off grid living. Now with panels so much more affordable, I think any decent modern fridge should run just fine off of solar unless you only have 300 watts of panels. Mine has that defrost cycle and power consumption with a 2400 watt system has not been a problem.

fratermus

Vandwellers commonly use 200w of panel to power a compressor fridge and incidentals.  I run a tiny 15L Alpicool that pulls 12A every 24hrs. I admit this wouldn't be a great fit for folks traveling with families.  :-)

Marc Kurth

BB. said:

Neil, a former moderator here did a test on a fridge/freezer with a kWH meter--And after disabling the defrost cycle, found that after ~24 hours, the evaporator started to freeze up and average daily energy consumption started to increase.

-Bill

Good input, Bill.

Marc

Dave Angelini

Probably saved someone from ruining a load of food.

The best refrigerator for offgrid is a power system designed to run it.
This is pretty basic, I would think.....

softdown

My great big chest freezer used just 2.6 kWH in six days. Keeping the food at 0F. It is also frost free.

Sorry - cant find a brand name on it. 

littleharbor2

No name BFFFF?  

softdown

littleharbor2 said:

No name BFFFF?  

It is likely covered by the stack of plywood leaning against a corner. I am constantly moving large stuff around it seems.