Solar/DC/AC - Cooler/Freezer

Solar/DC/AC - Cooler/Freezer

https://www.amazon.com/dp/B071JSLDFX/ref=emc_b_5_t

I may purchasing a cooler such as this for boating season 2019.

Anyone with experience on solar and DC power needs regarding 24/7 use relativity aboard boat?

Maybe introduction to other brands of similar cooler/freezer??

Options of daytime solar power / night DC greatly interests me. Heck, just solar in day with no opening of cooler lid during dark hours should do the trick!

Thanks! - Art

https://www.amazon.com/dp/B071JSLDFX/ref=emc_b_5_t

I'm pretty involved in off road stuff, the guys all swear by the ARB freezers. I have enjoyed ice cream on the beaches of Baja, with just a small twelve volt battery and a harbor freight solar panel!

Robertmark said:

I'm pretty involved in off road stuff, the guys all swear by the ARB freezers. I have enjoyed ice cream on the beaches of Baja, with just a small twelve volt battery and a harbor freight solar panel!

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Welcome to TF Robert - And, Thanks! I'll Google ARB freezers...

The primary "marine" brands are Dometic and Engel. I have a 40 qt Dometic. It draws 3.5 amps when the compressor is running. I use it as a fridge and it runs about 6-9 minutes an hour at an ambient temperature of 70F. That works out to about 110-160 watts per day. My 100 watt solar panel keeps up with it easily. It would probably draw at least twice that (220-320 watts/day) if used as a freezer. A 100 quart unit will draw 2.5-3 times as much (275-480 watts per day fridge and 550-960 watts per day freezer). You will need at least 200 watts of solar to keep up with that and I would prefer 300-400 watts. As far as batteries are concerned you will need at least a 100 amp-hr battery for a 40 qt unit and 200+ amp-hr for the 100 qt unit.



Another note is that these fridge/freezers use less power if they are full than if they are empty. I would always run one off DC since running them off AC involves about 10-15% more power from the batteries due to inverter losses.


I usually load mine just before an engine run so the run provides the larger power drain needed for initial cooling. Since these coolers are top loading opening them does not add much power drain. Putting warm stuff in does increase power drain.


Dometic also makes dual compressor models that have independent fridge and freezer compartments. They are worth looking at if you want cold drinks and ice.

I have 4 295 watt solar panels along with two banks of golf carts providing 850 AH storage and a 3KW true sine wave inverter that runs 24/7. The inverter automatically powers the AC loads when genny or dock power is absent.

Last season with my genny down my batteries always remained safely charged on moorings and anchor thanks to my solar. Besides normal lighting, we have 2 TVs, computers and an 8.2 cuft fridge with self defrost that keeps ice cream rock hard.

So whatever you select for a freezer you should be fine IF you have both adequate battery storage and the means to charge it while away from dock power WITHOUT running an engine or a genny.

I have an 10+ year old Waeco, I think they are Dometic now. Continues to work just fine. Used seasonally from May to September as a freezer. Also run on 12 volts. Solar panel 330 Watts keeps up with it, reefer and other boat loads during the summer season. Bought it used for $400, so no complaints.

I have an 8 year old 12v freezer that the PO bought for the boat. It is branded as NovaKool but it is a Chinese made unit that is private labeled. The ARB freezers are simply a newer version of what I have.

The freezer works really well. A single 365W solar panel on my boat will keep up with the freezer (sitting in the aft cockpit), the fridge/freezer in the galley, and the battery charging as long as we aren’t using the inverter for anything.

We have a Domestic CF50 purchesed 2 yrs ago after borrowing units the two previous years.
We use it only as a fridge.
This last spring bought 2 80w panels. That's all the space I have for them.

The panels keep up with the CF50 and our fridge when the sun is out. Both are Danfoss BD 35.

If the sun is questionable we still get an extra day or so with both fridges at which time we usually fire up and move anyway.

The CF50 is dark grey which gets hot so I had Sunbrella cover made to protect it from the sun and weather. The unit lives on the back deck so needs the protection. The cover though must not be tightly fitted. Air movement is needed and the cover sloped to roll rain off.

My previous borrowing taught me ,AND my friends that moisture in the controls will damage the control panel when , not if, it leaks.

They fitted a tight, snug cover which trapped condensation moisture between the cooler and the cover allowing that moisture to collect and damage the panel. In their case the cooler was on a totally enclosed back deck where NO rain could get at it. It was the tight fitted cover that caused the damage by trapping that condensation.

I was able to repair the damaged control board but avoid that problem with a good loose cover large enough to keep the weather and sun off and keep moisture from accumulating

Otherwise for two years of our own and the previous two years of borrowing it has been a great addition..

Thank you everyone! Great input.

Before next season I plan to put in new house bank [current HB is 9 yrs. old - getting long in the tooth, so to say - lol]. Also plan to add more solar panel. Will keep info from this thread in mind as I move toward having AC/DC/SP fridge/freez cooler like unit.

Art said:

Thank you everyone! Great input.

Before next season I plan to put in new house bank [current HB is 9 yrs. old - getting long in the tooth, so to say - lol]. Also plan to add more solar panel. Will keep info from this thread in mind as I move toward having AC/DC/SP fridge/freez cooler like unit.

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Art-

I don’t know what Vmp your panels have so that could limit you future panel selection. I went with 32Vmp panels that I have connected two in parallel that connect in series to another parallel pair. Yes, the distribution voltage can be hazardous if exposed (about 64-70V) which I happily put up with to enjoy the benefits of #10 wire. Heck, I could probably install #14 wire without losing much in the power distribution. I had half of the boat already wired with #10 from when I had lower voltage panels rated at 600W which I never saw.

We have an Engel MT-80 we bought about 10 years ago. We use it as an additional freezer until we finish the contents then turn it off. I just plugged it back in to check the draw, it pulls 2.8A on the 12V circuit, I didn’t try the AC.
At a temperature of 0 F it runs about 90% of the time, maybe a little higher. We back the temp off to 20 F for a reduced cycle time.
This trip is the first with a solar booster, the nominal 120W panel produced a peak current of 4.6A in full sun up on the South Coast of BC. The highest per-day amp-hours we got according to the controller was 28, so it may have offset the Engle.
It was enough to make me plan on a solar installation.

Yes, by all means solar! It is the gift that keeps on giving

Initially I was excited by Art`s post,thinking the fridge was solar powered by built in panels. But it`s not, it`s a conventional portable fridge.
We`ve used a similar Waeco/Dometic for years. I can pull it down at home on mains power, run it on 12v in the car from home to marina, and easily feed it by the solar panels on the boat. Obviously at night it uses battery. Although temp is adjustable, the problem is stopping it freezing things than keeping them cool.

Solar

Art,
I too use a Waeco freezer (12v) and have a solar array. The freezer is about 10-12 years old and still works great used for about 4 months each summer.

If I may suggest, over size your solar capacity as much as you can (reasonably). Remember you will have cloudy, rainy, or up here this year, smokey days where a smaller array may not meet your needs. Go with higher voltage and an MPPT controller for best efficiency.

I have 2 - 285 watt panels and an MPPT controller, with 6 golf cart batteries as a house bank (630 aH). My batteries made it back to 100% charge almost every day with no need to run shore power or the gen set.
Good luck,
Tom

Power is important , but insulation is the key to low power consumption.


Yes, adding insulation to the outside of the box does help, but at the cost of space in the boat.


www.sundanzer.com , might work for you.

I have a ARB 60 quart, I have used as a freezer on my boat for 3 years. It is a very rugged built unit and keeps ice cream rock hard. It has a safety feature that is owner adjustable to shut off to keep from running down a battery, a useful option when using on a 4x4 start battery when off-road.

I use a 40qt Fridge Freeze with a solar panel and dedicated 12v ATV battery. I have the lower 2/3 as freezer and upper 1/3 as fridge. Fridge Freeze made in San Diego, CA. Worked very well on my trip from Seattle to Alaska over a 3 month period.

foggysail said:

...Besides normal lighting, we have 2 TVs, computers and an 8.2 cuft fridge with self defrost that keeps ice cream rock hard....

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Foggysail - can you tell us about your fridge/freezer? Mine is aging, is NOT self-defrost, and freezes meat fine, but not ice cream. I have a similar power setup as you (4 solar panels, 760 AH of GC batteries).

Thanks!

I kept it out of my house bank as I wanted to keep it from depleting. I have a special forces solar panel I bought from sportsmans guide 40 watt but flexible, tied that to an interstate 12v ATV battery about 5 x 4 x 8 inches and powered my fridge freeze that way.
link is Medical Refrigerator & Freezers | Vaccine, Lab & Pharmacy - FridgeFreeze
I used this setup till I bought my latest boat last year.
Now its just sitting in my shop. Let me know how it works out for you.

I have a 60L Unique fridge/freezer and a 260W solar panel connected through an MPPT Controller to a pair of GC batteries. Dockside I do not hook into AC power, I leave the fridge/freezer (plus 5 and minus 5) running all week while I am away. No depletion of batteries through July and August and temps maintained.

BrianSmith said:

Foggysail - can you tell us about your fridge/freezer? Mine is aging, is NOT self-defrost, and freezes meat fine, but not ice cream. I have a similar power setup as you (4 solar panels, 760 AH of GC batteries).

Thanks!

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Sure! Way back when we puchased our new to us Silverton, it came with an 8cuft Norcold fridge. It was horrible, loud, things never seemed to get cold but I didn’t use a thermometer as I should have. Now the freezer, that was something else! I had to defrost that thing one time too many.

A friend who has a similar boat was cursed with a Norcold with the same performance. OK, the fridges were old and just maybe a new or newer Norcold would do a better refrigeration job but neither of us want to venture down that path with a new Norcold. Friend went ahead and purchased a different brand for about $1500....no defrost!

I searched the internet for an apartment style fridge that had dimensions close to that needed to fill the slot my Norcold rested comfortably in. Took awhile until I found that Summit offered a replacement with almost the exact dimensions, had a self defrost feature and could be had for only $500 delivered to my home. No way I could have had it delivered to the boat but that was not a big deal.

Now came the powering problem which I easily solved with an inverter.....into my second because I needed greater AC power while on anchor. What I have now is a 3KW true sine wave that runs 24/7 BUT it only powers the fridge when dock or genny power is missing. I just use a simple relay circuit to make this happen.

Batteries; and your going to need them no matter whose fridge you have. I installed two banks using 4 golf carts and I just could not keep them charged over a weekend away from the dock. So next I installed a Xantrex 1250 or maybe its a 5012 3 stage charger. Unimpressive! I had to run our genny for hours on anchor.....but I had rock hard ice cream and a frostless freezer.

I had to get serious! So my next move was to add solar...twice! My first attempt used 4 each 150 watt panels connected in parallel with a Vmp of 18V. I also had a named brand controller, PWM.....junk! I enjoyed charging of only about 25 amperes.

Next I installed a second hard top on my boat to accommodate more panels, sold the ones I had and purchased 4 Canadian made or at least marketed 295W panels, two on each hard top. They have a Vmp around 32V. Connected two on each hard top in parallel and then that combo connected in series. Increased my battery bank to 8 golf carts to form 2 banks providing a total of 850AH capacity.

And I junked the old contoller, replaced it with a Victron MTTP 150-70. WHAT A DIFFERENCE! Last summer my genny was down but my solar was up! They kept the bank charged with our fridge continuing to do refrigeration as advertised while we enjoyed watching TV on 2 each 32’’ sets.....Wifey and I agree on many things but definitely disagree on TV programs.

The above might be an exciting read but........Summit does not make my fridge any more. There are plenty of others though to chose from although one may need cabinet work to fit the thing on his boat. There are two camps here in the forums about marine vs apartment style fridges. I will never go with a marine unit although others take a different approach and never go with an apartment unit. It is entirely up to each to make the selection.

Good luck, if you require additional info from me I will do my best to help. OH before I end, I did install a Victron remote sensor. When I launched our boat this season with the batteries a little on the down side, I read 65 amperes of battery charge current provided with my solar.... the gift that keeps on giving

Good god foggy... which cost more... the boat or chargers, batts, refers, and AC, in the long run?? - LOL Just kidden - sorta!


But really - Thanks for the in-depth post!!

Art said:

Good god foggy... which cost more... the boat or chargers, batts, refers, and AC, in the long run?? - LOL Just kidden - sorta!


But really - Thanks for the in-depth post!!

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Art— it was late and Wifey always complains that I get carried away as the midnight hour approaches.

Cost? Heck, spending on my boat offers a better return than I would get from smokes and booze.

foggysail said:

Art— it was late and Wifey always complains that I get carried away as the midnight hour approaches.

Cost? Heck, spending on my boat offers a better return than I would get from smokes and booze.

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OMG - Ain't that da truth!

Art said:

Good god foggy... which cost more... the boat or chargers, batts, refers, and AC, in the long run?? - LOL Just kidden - sorta!


But really - Thanks for the in-depth post!!

Click to expand...

I started with a Norcold that was a huge consumer of amperage. By converting to DC only, I reduced that consumption to manageable levels, so was able to get rid of a whole bank of batteries. I attribute my very reasonable power consumption to the DC fridge. Had I moved to AC only, I would now have all those things Foggysail has, with the bill to prove it. My cost to change over to DC only was around $600 Cdn way back in 1995 or so. Sure, I have spent since then on updating my electricals, but none of that was due to lack of capacity, as would have been the case had I either stayed with the Norcold AC/DC or gone to household AC for refrigeration.
If my DC only ever fails, it will be replaced with the same.

koliver said:

I started with a Norcold that was a huge consumer of amperage. By converting to DC only, I reduced that consumption to manageable levels, so was able to get rid of a whole bank of batteries. I attribute my very reasonable power consumption to the DC fridge. Had I moved to AC only, I would now have all those things Foggysail has, with the bill to prove it. My cost to change over to DC only was around $600 Cdn way back in 1995 or so. Sure, I have spent since then on updating my electricals, but none of that was due to lack of capacity, as would have been the case had I either stayed with the Norcold AC/DC or gone to household AC for refrigeration.

If my DC only ever fails, it will be replaced with the same.

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Keith,

I have a NovaKool 9 cu.ft fridge/freeze. It is AC/DC. Are you saying that an AC/DC fridge is inherently less efficient than a DC only fridge? I had always assumed that the AC/DC fridge simply accepted AC and internally converted it to DC for the compressor. My assumptions could be wrong though

dhays said:

Keith,

I have a NovaKool 9 cu.ft fridge/freeze. It is AC/DC. Are you saying that an AC/DC fridge is inherently less efficient than a DC only fridge? I had always assumed that the AC/DC fridge simply accepted AC and internally converted it to DC for the compressor. My assumptions could be wrong though

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I look forward to learn the facts surrounding this matter!

dhays said:

Keith,

I have a NovaKool 9 cu.ft fridge/freeze. It is AC/DC. Are you saying that an AC/DC fridge is inherently less efficient than a DC only fridge? I had always assumed that the AC/DC fridge simply accepted AC and internally converted it to DC for the compressor. My assumptions could be wrong though

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Dave:

In the case of a late 80s or early 90s vintage Norcold AC/DC ( I can't speak of more modern units, as they may? have sorted out their priorities) the fridge operated only on AC, so to make it AC/DC Norcold put an inverter in the fridge case. The unintended consequence of that was to up the consumption of power in DC mode to account for the huge inverter loss on that old technology. I was able to get an amperage measurement of over 10 amps DC on that unit. The RV market Norcold was after could tolerate that priority to AC far better than the Marine market, as most RVs are set up to generate or operate on Propane when not plugged in, only needing to be on DC while driving.

After conversion to DC (Danfoss unit) my measurement dropped to 2.7 amps and run time didn't change. That change alone allowed me to add a freezer drawing 3 amps and cut back from twin 8Ds + twin 4Ds in House banks A and B, to 4xGC6vs as my sole House bank.

As your boat is somewhat newer, it may have a NovaKool designed for the DC priority that is required to get the low amp usage that is required while at anchor. Measure your DC draw if you can and you will then know what you have.

koliver said:

Dave:



In the case of a late 80s or early 90s vintage Norcold AC/DC ( I can't speak of more modern units, as they may? have sorted out their priorities) the fridge operated only on AC, so to make it AC/DC Norcold put an inverter in the fridge case. The unintended consequence of that was to up the consumption of power in DC mode to account for the huge inverter loss on that old technology. I was able to get an amperage measurement of over 10 amps DC on that unit. The RV market Norcold was after could tolerate that priority to AC far better than the Marine market, as most RVs are set up to generate or operate on Propane when not plugged in, only needing to be on DC while driving.



After conversion to DC (Danfoss unit) my measurement dropped to 2.7 amps and run time didn't change. That change alone allowed me to add a freezer drawing 3 amps and cut back from twin 8Ds + twin 4Ds in House banks A and B, to 4xGC6vs as my sole House bank.



As your boat is somewhat newer, it may have a NovaKool designed for the DC priority that is required to get the low amp usage that is required while at anchor. Measure your DC draw if you can and you will then know what you have.

Click to expand...

Yeah, I believe (and I could be wrong) that the newer AC/DC refrigerators do the opposite of what your old refrigerator do. My NovaKool uses a Danfoss compressor that I believe is native 12v and it has an internal conversion from AC to DC that is active whenever there is AC present. I imagine there is a loss in that conversion, but not as much as converting inverting DC to AC. Plus, I’m much more willing to take a loss when plugged into shorepower than I am when sitting at anchor.

I also don’t see any big advantages to having an AC/DC unit like mine over a DC only unit like yours. I usually have my battery charger running all the time when on shore power as it is.

Hey Art. I run a Waeco CDF-35 which is an older model of what your link shows. A single 250 watt panel keeps my batteries topped up and the fridge running just above during the without my main charger plugged in.

The 250 watt panel may not keep up if the fridge is opened often on an overcast day, but 99% of the time the battery bank is 100% charged before noon each day.