Super efficient 12 volt chest freezer

Hi all;  
For 30 years or more we have kept our chest freezer at a neighbors house. $100 a year and I was happy to pay it.  (Hmmm $3000+)
Our freezer was old when we bought it for $150.... oh back around 1990. So old it has an original equipment plug in that only has two prongs of the same size!
This fall the home where our freezer has been living, was put up for sale.  We were told the freezer could stay, at least until it sold, but after that all promises were off.
So , search out another neighbor and keep paying rent... or finally bring it home?

We brought it home just after Christmas.
Had no idea how much power it would use...  OMG !!!  40+ amps @ 12 volts!!!  Sure it drops down to twenty amps after a little while but it isn't off very long before it turns on again!  
Ouch very hard on the battery's. This is winter, how much will that power sucker run in the summer?   More than I have power for i'm sure.  Even now, I need to run the genset at least twice a day to keep the battery's up and the freezer temp's down. I have a remote temperature sender from my weather station inside the freezer to make sure nothing thaws.
Plan B needed implementing.
Plan B consists of a class A big time expense!
A Sun Danzer super efficient 12 volt large capacity chest freezer!
To have it delivered to my door, its a whopping $1754 !  (Hmmm I payed out over $3000 you say...)
Tax's are filed , and as soon as they arrive, the freezer is being ordered !
I can hardly wait.
We already have 600 watts of panels to go up on the barn. They say a 275 watt system is plenty in most areas.
I can't get the panels mounted until spring, but I can run a small battery charger to maintain a 12 vt battery off my current system until the weather breaks.
Here's a link all about it from where I'm buying from    https://www.solarpanelstore.com/collections/efficient-appliances/products/sundanzer-dcf390-freezer

EDIT)   The down load at the bottom is the freezer data  sheet. By going to the store first, you can see the data sheet there instead.

Interesting. I respect your opinion on this a great deal. Usually we consult people to go with AC fridges and freezers so I have questions for you.  Did you think of going with an off the shelf AC model? Standard AC appliances have come a long way in 20 years almost matching the dc options. Energy usage is slightly higher  but cost is a third the money which could buy more panels.
Next would be did you consider splitting the purchase into two smaller AC units? During low freezer season you can just shut one off making up for any energy loss. Up to 9Cu Ft you can get the R600a freezers that claim a 10 percent lower energy usage over R134a which I think Sundanzer still uses. I have not seen a DC freezer using R600a yet... Is servicing of the unit available where you are? A client of mine opted for a SunDanzer and their ability to service the unit here was non existent. 6 years and dead as a doornail. Their customer service was just plain awful and no local refrigeration tech would touch them.
With the utmost of respect; curious not confrontational.
Cheers,  David

Hi David;
Thanks for your response, and your opinion. I respect everyone's opinion, I just might not follow it.
One reason I'm choosing to go DC rather than AC, is not needing to keep an inverter in an unheated barn. One less, expensive electronic item to unexpectedly go bad.   The barn currently does have AC from the house system. I would like to eliminate that all together. Leave it in place , just stop using it daily.We do shut off the house power each night. A stand alone DC can just do its thing. I will be remote monitoring the freezer temps in the event of a problem.
Occasional lighting in the barn and attached wood shed plus the freezer are the only needs for power out there.  

As far as modern a/c fridges. I personally know of none that come close to the insulation thickness the sun danzer has, 9cm thick. I could be wrong. It does use the R134 refrigerant.
Another thing is construction, a steel outer shell and an aluminum inner. The conventional  ones I have seen are plastic inside. Some have auto defrost... lets see, thaw your food to melt the ice and then refreeze it ??? Seems counter productive to me. If my freezer needs defrosting, I'll just do it during the winter.
As far as 2 smaller freezers. I considered it but decided against it.. We raise a pig each year, we shoot at least one elk and 2 deer and some years we buy a 1/2 beef, plus all the produce from the garden. I would rather have a large organized freezer than two smaller packed ones.
From reading in other forums I expect the sun danzer to pull 3-5 amps @ 12vt  I'm pretty confident no AC freezer will draw that little, or need to run as infrequently as a super insulated one.
I realize that our 1970's freezer is about as inefficient as can be. It has to go.
We plan on offering it free to any single parent who needs one.

thomas rubino wrote:Hi David;
Thanks for your response, and your opinion. I respect everyone's opinion, I just might not follow it.
One reason I'm choosing to go DC rather than AC, is not needing to keep an inverter in an unheated barn. One less, expensive electronic item to unexpectedly go bad.   The barn currently does have AC from the house system. I would like to eliminate that all together. Leave it in place , just stop using it daily.We do shut off the house power each night. A stand alone DC can just do its thing. I will be remote monitoring the freezer temps in the event of a problem.
Occasional lighting in the barn and attached wood shed plus the freezer are the only needs for power out there.  

As far as modern a/c fridges. I personally know of none that come close to the insulation thickness the sun danzer has, 9cm thick. I could be wrong. It does use the R134 refrigerant.
Another thing is construction, a steel outer shell and an aluminum inner. The conventional  ones I have seen are plastic inside. Some have auto defrost... lets see, thaw your food to melt the ice and then refreeze it ??? Seems counter productive to me. If my freezer needs defrosting, I'll just do it during the winter.
As far as 2 smaller freezers. I considered it but decided against it.. We raise a pig each year, we shoot at least one elk and 2 deer and some years we buy a 1/2 beef, plus all the produce from the garden. I would rather have a large organized freezer than two smaller packed ones.
From reading in other forums I expect the sun danzer to pull 3-5 amps @ 12vt  I'm pretty confident no AC freezer will draw that little, or need to run as infrequently as a super insulated one.
I realize that our 1970's freezer is about as inefficient as can be. It has to go.
We plan on offering it free to any single parent who needs one.

Thank you for the response. Everyone has different conditions on the ground. I can tell you from experience that my 10 year old Frigidaire  5.5 CU Ft set to 3/4 thermostat holds -17C and uses approx 400W Hr per day in the heated basement.  It has metal exterior and aluminum interior as well. Manual defrost. This is actually 25 percent below its Energy start rating which makes me wonder. I will be buying a R600A unit when we build the new house which has the 9cm insulation and manual defrost.  I totally understand the desire to avoid the inverter if you shut it off at night. Its not much of a possibility here anymore with the mandated arc fault plugs, ground fault plugs, and hardwired Smoke an CO detectors that have a tiny continuous draw.
Cheers,  David

Hi David;
What make / model freezer were you planning on purchasing?  With the R600 and the 9cm thick walls?  
I did a quick search and did not find any AC products willing to mention how thick the insulation is.
It will be good information for me to share with my on grid friends.

thomas rubino wrote:Hi David;
What make / model freezer were you planning on purchasing?  With the R600 and the 9cm thick walls?  
I did a quick search and did not find any AC products willing to mention how thick the insulation is.
It will be good information for me to share with my on grid friends.

the danby premiere line was the one I measured the wall thickness on. I could not find specs on the insulation on their standard brochure though...

Thomas

Here is an article by a guy thinking about redoing his onboard refrigeration. The boating industry has a long history in 12volt applications. This article may not be aimed directly at your situation but it's not a bad overview of what's available out there along with some pro's and con's. Also, it provides some names you may not have looked at.

https://www.passagemaker.com/technical/marine-refrigeration


Regards,
Rufus

I have never understood how freezer manufacturers can get away with so little insulation. I bought a cheap used chest freezer for weird reasons, and ended up encasing it in 2.5 inch styrofoam (except where the motor is so stays cool.) Improved it's attitude quite a bit.  Part of why I bought it was it's old enough to not have a defrost cycle (Who thought THAT up?) and it's run this long, high odds it's fairly indestructible.

I'm glad you are looking at freezers that are made to work well to start with, no modification required.

:D

Yes, it is amazing that almost all do not list how much insulation is in them.

David ,thought the Danby he wants might be pretty thick insulation but the manufacturer isn't saying in the spec's.
I found a Summit model EL31LT  with 4" + insulation 10.9 cubic foot , runs on A/C  cost is almost $2300!!! holy cow batman ! Make's the 13.9 CF 12 volt model kind of affordable.

I agree. Insulation is one of the most important things to have around a fridge, freezer or even a hot water tank, but I can also see why they only put so much on....to make it compact. Large is good on the inside but not good on the outside. Fortunately though they do make jackets to fit around them or DIY insulation like what Pearl did.
Good luck in your search for the perfect freezer Thomas!  :)