Wednesday, October 22, 2014

Off-Grid Gear -- Refrigeration

One particularly challenging aspect of being non-electric is the need for refrigeration.  When we first moved into Little Shouse on the Prairie we were completely non-electric.  No. Power. Anywhere.  I had a milk cow, which resulted in fresh cheese and butter and yogurt, and nowhere to keep any of it cool.  The cheese and butter were somewhat forgiving but the milk was not.  If I couldn't cool the milk in a relatively short amount of time, and keep it cool, I ended up with a curdled mass that was only fit for animal use.  Desperate for a solution, Sir Knight and I bought a heavily insulated cooler and filled it with blocks of ice.  Although better than nothing, the cooler was a sad substitute for a real refrigerator.

Within a few weeks of moving in, we had a large propane tank installed and plumbed to the Shouse.  Originally we had intended on using the propane only for our range.  Quickly, however, we realized that we needed another solution for refrigeration. 

Our original propane stove was an enameled Wedgewood from the 1950's.  It was the gem of my kitchen!  At the same yard sale that we had purchased the stove, we stumbled across a 1950's model Servel propane refrigerator.  For a few hundred dollars, we bought the stove and the refrigerator.  My initial thought was that we could use the propane stove only when we really needed it, but we couldn't turn the refrigerator off if we weren't using it, so not wanting to waste propane, we didn't hook up the refrigerator.

More than a few gallons of spoiled milk, blocks of ruined cheese and pounds of rotten meat later, we finally gave in and lit the propane refrigerator.  Oh, it was heavenly!  Although rather small for a refrigerator, the Servel was huge compared to a cooler.  No longer did I have to fish wet packages, bags and bottles from the bottom of a swampy cooler!  Now I could keep gallons of milk ice cold, leftovers fresh and I even had a small freezer for ice cube trays.  Wow!  What a difference a tiny blue flame could make!

Over time, I found that I absolutely loved our propane refrigerator.  It was small, but efficient.  In the whole scope of things, it used relatively little propane and made our lives so much easier.  But, out of all of the reasons to love the Servel, silence was at the top of my list.  Really!  Propane refrigerators are completely silent.  They don't cycle off and on.  The flame just burns silently, steadily, providing continuous, silent refrigeration.  Oh how I loved that little workhorse.

One morning, after using the Servel for about 6 years, I awoke to a warming refrigerator.  Laying on the floor to inspect the burner, I quickly discovered that the flame had gone out.  Sir Knight re-lit our refrigerator and it continued on as before - for about 2 weeks.  Again, a pool of water on the kitchen floor indicated the burner has gone out. Sir Knight surveyed the situation and discovered that the burner had burned out. Calling a propane refrigerator repair center, I was quickly informed that the older model Servel that we owned had been part of a lawsuit (the burners quit working after over 50 years and a number of people had died of carbon monoxide poisoning in their cabins) and there were no replacement parts available.  We were sadly reduced to the cooler once again.

Shortly after our propane refrigerator quit working, we helped a friend move his entire household.  A week later, a pick-up came rumbling up our driveway bearing a gift from the friend that had moved - an older model Sunfrost refrigerator, specially designed for off-grid use.  The Sunfrost was electric, however, it was designed with the alternative energy household in mind.  Our refrigerator was large, with two compressors - one for the freezer and one for the refrigerator.  It was short and wide, making the refrigerator inconvenient, however Sir Knight remedied that problem by building a sturdy box for the refrigerator to sit upon.  Now, not only was the Sunfrost at a convenient height, but the box also provided extra kitchen storage!

I had a love/hate relationship with the Sunfrost refrigerator.  It was huge, but had only three awkward glass shelves in each section.  The shelves were positioned so that it was difficult to fit anything into the refrigerator except into the voluminous middle shelf.  The refrigerator was so deep that I was constantly digging everything out to get to items in the back.  It was nothing short of frustrating.  Along with the poor organizational qualities, we found that our Sunfrost didn't work particularly well.  The refrigerator froze everything that migrated to the back and the freezer refused to freeze anything other than ice cubes.  While researching our refrigeration issues, Sir Knight discovered that Sunfrost tested their refrigerators differently than industry standards for a "regular" refrigerator.  Sunfrost tested their refrigerator efficiency at significantly higher temperatures than their Energy Star counterparts.  What this meant for us was that our refrigerator required much more energy than advertised.  We turned our refrigerator down, trying to keep things cooler, causing the compressors to cycle off and on more frequently and still not achieving the cooling that we desired!  On top of that, the fridge was not frost free.  The entire top and back of the fridge would turn into solid chunks of ice, all while not freezing anything in the freezer!

After eight years of no popsicles, no ice cream and forgotten left-overs, we made the jump.  For my birthday this year, Sir Knight bought me a used, Energy Star Amana refrigerator to replace the cursed Sunfrost.  I was so excited!  My "new" fridge had drawers, shelves and cubbies everywhere.  It was a simple refrigerator with the fridge on top and the freezer on the bottom.  The evening we brought it home, I anxiously waited to see how it would respond to the modified square waves of our off-grid system.  I wasn't sure if the surge (when it came on) would be too much for our inverter, or if it would use a ton more power.  I wanted to have a "real" refrigerator so badly that I was constantly checking the Tri-metric (volt meter) to see if it was going to be viable.

As soon as we plugged the fridge in, it cycled on.  Really, it only used a little bit more power during the surge than our Sunfrost (our Sunfrost surge was about 12 amps and the Amana topped out at 15 amps).  But, the really cool thing was that when the fridge was running it used less electricty (about 6 amps versus the Sunfrost's 8 amps) than our old refrigerator!  Less!  And, as icing on the cake - the Amana Energy Star refrigerator could freeze anything - hard, and it was frost free!

Suffering for eight years with a substandard refrigerator was ridiculous!  We had read one too many solar articles, listened to one too many experts and based our decisions on faulty information.  We couldn't be happier with a plain old Energy Star refrigerator, despite what the "experts" say.

All in all, my favorite fridge was the propane Servel.  It had drawbacks (tiny freezer and small fridge) but I LOVED it's silent operation (and it was pretty cute!).  But, if I had to do it all again, I would definitely choose a plain jane Energy Star refrigerator.  When we had no alternative energy, the Servel was the only way to go, but with solar panels, the Amana is wonderful.  It runs flawlessly, keeps cold things cold and frozen things frozen.  It is convenient, easily organized and just plain awesome.  Sometimes I walk into my kitchen and think "where have you been all my life" (I know, sad isn't it?).

If you are just starting your off-grid adventure and you have a reliable alternative energy system, I would highly encourage you to buy a simple Energy Star refrigerator rather than an expensive "off-grid" fridge.  Although a DC Sunfrost might be worth the investment, we found that our AC model certainly wasn't.  In the worst case scenario, a root cellar would still be the best off-grid cooler, but if you can get your off-grid system set up now, an Energy Star refrigerator is your best bet.


  1. Wow, did this ever bring back memories from my time living off the grid. We had an old RV propane refrigerator that was so small and then we decided to go "whole hog" and bought a new Dometic. I was in hog heaven! It was large enough, it worked great and, as you've noted, it was quiet.

    I love walking down memory lane via your posts about your life.

  2. I calculated up the difference in cost of a propane and so called off grid refers and found it was cheaper to buy any energy star model and put the difference into more solar panels. Then you have a real refer and no propane bills. Its works excellent.

  3. I got a small 2 way fridge from a old camper a friend was going to scrap for the metal, Fridge works on 115 volts haven't tried the propane hookup yet,hopefully it will.
    good luck with you new fridge.

  4. I'm an elder female totally off grid. Spent a miserable summer using ice. Definately not practical. Finally salvaged old rv propane frig. Love it. Small but serves basic needs. I found I didn't need to invest in huge propane tank. I use 5 gal propane bottles that I can easily handle. I have been able to slowly, affordably buy more bottles. I also use a outdoor cooking grill with side burners with same bottles.

  5. My wife's folks had a propane fridge. It ran without any problems for over 40 years. It wasn't big but it was efficient. I will agree that some of the new fridges and freezers are very efficient. Thanks for the greenies for than, not so much the low volume flush stools.

  6. I have always planned to go offgrid one day and buy a sunfrost refrigerator, looks like i can save a little money on a regular one now!

  7. Years ago, I saw a kerosene refrigerator-no freezer section though. The thing was from the 1930s(before the Rural Electrification Program...or for those who didn't have a 32 volt "donkey" generator), and, at that time, it had been in continuous operation for about 50 years. A gallon of kerosene lasted two weeks(so I was told). I don't remember the manufacturuer, but it looked almost cartoonish. I think you had to clean out carbon buildup every now and then.
    In the late 1990s, some friends of mine had a 12VDC/120VAC/propane fridge-it used heat to move the refrigerant around, and was silent in use. I think it had a small freezer section, but I'm not sure. It was about twice the size of those student-fridge "beer cube" jobs. For off the grid (and on grid types as well), LED bulbs are great-my electric bill went down by over half-and the only changes I made was to slowly replace all the bulbs in the house with LEDs (one per payday-for me, that's five months). Given the drop in the electric bill, they'll for themselves in 18 months. While I don't buy the 20 to 46 year rated life span, if they last 5 years, they're a good deal.
    Very little in the way of heat, and the color is better than CFLs.

  8. Some years ago our refrigerator died. It was replaced with a huge Samsung that had the features my wife wanted. It had an Energy Star rating at the bottom of the energy usage range. When I computed the average power in Watts from the annual usage on the Energy Star sticker it came out to just 60 watts. I could hardly believe this monster of a refrigerator with large bottom freezer, French doors, and water and ice through the door could use so little power, but 3 months of checking with my Kill-A-Watt meter showed it was so. I too would highly recommend buying a "normal" modern refrigerator with a low Energy Star power usage rating.

  9. Why does no one mention going to a chest style reefer? A regular upright unit dumps all the cold air out onto the floor each time it is opened. While you do have to dig around in a chest to get things out, still saves all the cool air inside. Look into 12V/24V Sundanzer chest reefers....pricey, but well made and can even run directly off a 100W solar panel.FYI

  10. My mother (now 85) has a Home Economics Degree and always said that of all things modern refrigeration is what she would miss the most should she lose it........Nadokadn

  11. Do you realize that your propane refrigerator is actually an Ammonia cycle frig? Most Rv's have them. It will cool with any source of heat. You could purchase a complete cooling unit and power it with a fresnal lens or a rocket stove as well as propane. Go here to learn more
    Watch this animation that shows how it works

  12. Hi Enola

    You mentioned that you lost lots of cheese when you didn’t have refrigeration.
    I used to believe that cheese needs refrigeration. However, in the past 2 years I’ve learned that it doesn’t IF is properly sealed away from the air. In the old days this was done by wrapping the cheese in chest cloth and then coating it with wax.

    I now buy mild cheddar and Monterey Jack cheese at the supermarket in 2 pound blocks that are sealed in a plastic wrapping. I store these in my “whine cellar” on shelves in a cabinet with doors that exclude light. In the summer I open the cellar windows at night to let in the cool night air and close them again in the morning before things begin to warm up. This keeps the cellar at temperatures that never exceed 70F on the hottest summer days (>95F).

    Even after 9 months of storage my cheese is not only palatable it has “aged” and, at least to me, far more flavorful – like the expensive "well aged" stuff. Now, there are other changes that sometimes occur – but these aren’t a problem. Sometimes the cheese off-gasses and inflates the wrapping. Other times, the cheese exudes some liquid that is a bit messy when you open the package months later. The gas has no noticeable odor and it’s not flammable (I tested it). The liquid has a very pale yellow color, a faint but pleasant odor, and feels slightly oily. I just drain it off, wipe the cheese dry with a paper towel, and then enjoy it.

    I also store Smart Balance buttery spread in the same way. After 9 months that is no separation of ingredients or change in flavor.

    I’m sure that both cheese and Smart Balance will both be “good” after several more months of “whine cellar” storage – storage that is continuing as I slowly expand my supply of these items.

    Hangtown Frank

    1. I the first paragraph I said "...wrapping the cheese in chest cloth...". I meant to say "cheese cloth".

      And, yesterday I opened another well aged 2 pound block of "whine cellar" cheese. The plastic wrap had ballooned out a bit and the cheese had exuded a bit of liquid which I wiped off. The flavor was magnificent.

      Hangtown Frank (aka Fat Fingers Frank when typing)

  13. Hi Enola,
    We decided on an Energy Star regular fridg when we went off grid almost 8 years ago. Never had much trouble and we turned it off at night to save even more power. We are set up with one of our back rooms as a storage room and in the winter is stays at about 45 degrees in there. Last year we unplugged the fridg and started making ice outside on the porch. We kept most things in the back room, but had a few things in the top freezer of the fridg with the ice. It worked great! The ice lasted 2 days and by then there was another block of it ready and I changed them out. Everything kept cold, had lots of storage in the back room and we saved the energy to run the chest freezer all winter long. Sorry you suffered as long as you did, but you learned and got through it. That is the most important thing!
    Judy in Idaho

  14. We moved off-grid just over two years ago. We're still hauling ice, which we keep in a non-working 4.5 cubic foot chest freezer. It works well, but hauling ice is getting old. I found a solution almost two years ago, but one project after another and my lack of confidence in my craftsmanship have thwarted me in building the very simple prototype.

    Refrigeration and freezing do not require electricity, fuel, external heat, water or ice. Comically, The United States of America, Department of Energy, knew it almost thirty years ago. Uncle Sam owned the patent! See US Patent 4624113, University of Chicago, representing Argonne National Laboratory, on behalf of USA, DOE, 1985.

    I have refined the invention for common refrigeration. I intend to have a prototype soon, if I have to pay someone to build it. Anyone who is handy with tools can build it. See

  15. Absorption cycle refrigerators like propane powered RV refrigerators are not very energy efficient compared to a modern compression cycle. However, if you use a "3-way" RV fridge (propane, 12 volts DC or 120 volts AC) you can set it up so that the fridge uses 12-15 volts directly from a small solar array (an east-west array is best for this) when the weather is sunny and it simply switches to propane at night or inclement weather. While you can't remove a battery completely from the system (modern 3-ways require 12v battery power for the electronics) you won't need the massive batteries that modern off-grid whole house arrays call for.

    @Jack Panella, your blogspot hasn't been updated for some time. Has there been any progress on the skyfridge idea?

  16. It is unfortunate you had that experience with Sunfrost. There are other companies out there that offer DC refrigerators and freezers. The main advantage is the reduction in cost; no need for as many panels or batteries, and no need for an inverter if you're just taking the fridge/freezer off-grid. We offer solar refrigerators and chest freezers (that can be turned up with no additional parts required to operate as refrigerators). Feel free to take a look: