We have a 13' uhaul and a Nissan Quest van for a TV.

We are primarily interested in basic camping ( mainly to save money ) and thus are concerned over keeping decent food AND keeping the battery charged. Along with this, we seek simple solutions.

We are considering getting one of those refrigerator/freezers that resemble a big cooler. This is an example------ EdgeStar Portable Fridge / Freezer - 43 Qt.

These only draw 2.5 amps and typically run about 20% of the time ( 12AH/day ). Since there is no practical way to keep it in the trailer, we intend to keep it in the van where we have ample space.

Then we expect to mount a 125 watt solar panel on the luggage rack of the van to run the frig, and via a cable, keep the camper battery charged as well. The good part of this is that there is room on the van for the panel, and we can park the van in the sunshine while the camper remains in the shade. In addition, the panel can be positioned to face the direct rays of the sun by adding a tilting mount.

A selector switch will select the load between the panel and the TV alternator as required.

We welcome any comments, good or bad, as to the practicality of this idea because we only THINK that's what we want.

When we had our Compact Jr. we used an Igloo brand Thermoelectric Cooler in a similar fashion. I was underwhelmed with the performance.

I like your idea.

These only draw 2.5 amps and typically run about 20% of the time ( 12AH/day ). Since there is no practical way to keep it in the trailer, we intend to keep it in the van where we have ample space.


Judith:

I think the spec says that it draws 2.5 amps at 24 volts or 4.5 amps at 12 volts. This is quite a bit of power draw on the battery if the solar panel is not providing enough power.

My understanding of solar systems is that they need a "deep cycle" battery to work well -- like the one in your trailer, not the type of battery which will be in your vehicle. You will also need to have a controller to manage the charging of the battery from the solar panel.

When you are driving will your alternator have enough power to run the cooler in addition to everything else? (From other posts I understand conventional trailer fridges often use more power than is supplied to the trailer during travel.)

If you stop, will the cooler run down the vehicle battery or the trailer battery?

Brian

You are correct in that the ad does indeed say 4 amps at 12 volts. However, other ads quote 2.5 and other manufacturers also quote 2.5 amps so I am getting confused on this issue.

On the other hand, even 24 amp hours is not a whole lot to a deep cycle battery. Remember, the 24 AH is for all day and not just over night.

I would expect the TV alternator could handle an extra 2.5/4 amps while under way.

The TV battery/alternator would only be selected while driving----if needed.

Be aware that this is a refrigerator/freezer and not one of those cooler/warmers.

I'm not exactly clear on your setup. It appears your deep cycle battery is, or will be, in the trailer, and not in the TV(?).

If you hook up the PV panel to a controller located in the TV, then hook up the charge out from the controller to the battery in the trailer, and then connect the load terminals on the controller to the fridge, then you'll lose power to the fridge as it gets dark, so no power overnight.

However, you don't need to use the "load" output from the controller. You can hook the PV to the controller, and the controller's charge output line to the battery. Then you hook up the fridge to the battery, along with any other loads (lights, furnace, etc.). These are then in parallel with the panel. You would then need a 12v power line from the trailer to the fridge in the TV. Maybe a short line for when under way, and a longer one for when the TV is parked in the sun. Or maybe just coil up the end of one long one while under way.

Actually, 24 amp/hrs per day can be a lot for a deep cycle battery, and more so if you need to run electric lights, television, computer, furnace fan, or whatever else. But, one rule of thumb is for the battery capacity to be 4 times the expected daily usage, so if you have a 100 amp-hr deep cycle battery, and don't need to run anything else, you should be OK. Depends on other variables, but a 120-watt panel should put out enough to replace the usage, on most days. I think.

At any rate, you should do the math, and add up all your expected usage, and determine your required battery capacity and required charging ability accordingly. One major factor is that at some point, around 70-80% of full charge, the battery can't accept the full output of your panel. The charge rate slows down dramatically, and if your charge controller doesn't compensate by reducing the output of charging amps, the excess output will only go to producing gas and boiling off the water, both of which are bad for the battery. Of course, if you're running the fridge at 4.5 amps, and the panel/charge can put out 10 amps, you have up to 5.5 amps for charging the battery at the same time. Another factor is whether you plan to be out for long periods of time, or just 2-3 days max, as you could gradually run the battery down to 50%, then bring it back up to full charge after you get home.

There are plenty of books and web sites that provide detailed information and worksheets to help you calculate your battery capacity and charging capacity requirements fairly accurately -- at least accurately enough to avoid problems once you get out on the road. One book that I can recommend is Managing 12 Volts. How to Upgrade, Operate and Troubleshoot 12 Electrical Systems, by Harold Barre. It may have more than you need to know, but it does simplify the process of determining your requirements, and keeping your system working well.

Sorry - I got a little carried away. Hope this is helpful...

The main reason for getting the trailer was not so much for camping as being able to have a place to sleep and eat at days end as we travel. That is not to say that we will never camp, But there will be times when we are on the road each day and the TV will keep the frig going leaving the SP to baby sit the battery. OR, in addition keep the battery up should the sun fail.

I have read that the camper three way refrigerators pull about 10 amps and in addition, I would have to cut large holes in my camper in oder to provide sufficient cooling. For these reasons I am thinking along the lines mentioned.

Presently, our trailer only has a couple of lights and a fan for the furnace when needed. We do not intend to add any signifigant extra electrical loads. We lived on a boat for eight years. We had everything electric you could imagine including a 6KW diesel generator. Quite frankly, I got sick and tired working at trying to keep all these systems operating and am trying to keep my camper as simple as possible and still eating more than tang and granola bars!

If I had a fridge, I would require propane, would like to have AC also, and woudn't care if if didn't have 12V. I had a 3-way fridge in my 1999 Casita, and I never ran it on 12v. I started it up on 120V about 12-24 hours before leaving home, and used propane while driving and while stopped. It froze ice cubes and kept ice cream solid (or at least solid enough for practical purposes). I guess the new ones that you're looking at are more efficient on 12v than the old 3-ways, though.

As you say, cutting vent holes in the camper can be a deal breaker, but I've never seen that as a problem, other than requiring more work. Another drawback with propane is that you have to remember to turn it off when fueling the TV, and before entering some tunnels (but that's mostly east of the Mississippi), and these were not problems for me.

I recently bought a trailer with no fridge. It probably had an ice box once, but if so, it was gone when I got it. I decided to stay with just an ice box rather than try to install a fridge, just to keep it simple. I don't need a freezer, and a cooler has always been adequate for me in the past.

By the way, it appears that the electric fridge/freezer units that you are considering appear to be usable as one or the other but not both at the same time, right? If I had one, I'd probably set it on freezer mode while on shore power, then add the food & beverages and turn it down (up?) to fridge mode just before taking off on a trip.

I like the basic idea, but haven't been overly impressed with the ability of thermoelectric/Peltier coolers, which eat a lot of electricity and still can't stay ice cold on a hot day. They're expensive, too. On a dollar-for-dollar basis my guess is you'd be a whole lot better off with buying an oversize traditional cooler and packing it with ice. A good cooler can stay cold for several days at a time with two bags of ice packed in to them, and ice is a lot cheaper than a solar panel, dual-use battery, charge controller, and a thermoelectric cooler.

I have a 105 watt solar setup on our trailer, which happily runs our LED lights, a furnace with an electric blower, chargers for cell phones and other battery-powered devices and entertainment equipment, but it doesn't run our refrigerator. Likewise, the second trailer we are rehabilitating will have a solar panel, probably just 50 watts because we'll be using a Wave 3 catalytic heater that doesn't use battery power at all to keep the trailer warm, but again we'll have LED lights and a propane 'fridge.

I like propane/110v AC refrigerators. $1 of propane will keep the 'fridge cold for a week or two, and it'll run on shore power when you have hookups. Yes, you do have to cut holes in your shell and run the gas lines (not a task I'd encourage you to do unless you're an outstanding handyman), but if you have those skills and can find a functional used refrigerator you'll probably find it's a whole lot less expensive.

Just as a note, the tunnels I know of (mostly on I-95 because that's where I've been traveling lately) do not just require you to turn off the propane, but do not allow you to go through if you have propane tanks at all. Of course there is always an alternate route, so it's not a deal breaker for me - but just mentioning.

Many boaters are using the Engel 12/120v coolers and I hear very good reports from them; I've never used one though.

Raya

Go with a straight DC fridge like a norcold to replace the icebox. The DC0040 pulls 4 amps at max draw, but still you've gotta consider that's 4 amps per hour . Even on the hottest days, the compressor only runs maybe 50% of the time. No cutting and no venting, just screw it an. Get a few golf cart batteries and you'll have at least a 200 ah reserve. And that's for the cheap ones. Some of those big AGM monsters have like 400 ah+ !!

I'll bet you could do the job for less than the cost of the solar panel, solar controller, mounting hardware, etc. And even after all that, then what do you do if you're boondocking and the sun doesnt come out? And as Peterh said, even a big panel will have a tough time keeping up with constant demand appliances like a fridge.

How does that calculate though?

Say it draws 4 amps and runs 50% of the time. That's 48 amp hours per day (24 hour day). A battery only wants to be drawn down to about 50% of it's rated amp hours (if you want decent life out of them), so for say, 4 days, you'd need a battery bank that would store about 400 amp hours.

Two golf cart batteries (such as Trojan T-105s) wired together to make 12 volts give you about 225 amp hours. So you'd want two banks of them (4 batteries). That's quite a bit of weight, plus you'd want other batteries for other stuff, like lights, maybe furnace or AC, entertainment, etc.

And then you would have to put all those amp hours back IN somehow before you could continue on refrigerating (like if you were out for more than four days).

Maybe I'm not thinking of this correctly So far, to me, I can't see how it would work as well as propane, on just the batteries (if I understood your suggestion correctly) without solar panels or etc. to recharge the bank.

Not to discourage anyone from coming up with new ideas; just putting some numbers out there (and again, please correct me if I'm wrong).

Raya

No, you're right. 50% is a real high estimate though. As long as you aren't opening and closing the door every 10 minutes, I think 25-30% run time is probably a bit more realistic even in a high demand environment (high ambient temperature). And I was mistaken; actually max draw is 3.5 amps on the 0040 according to Norcold, although I haven't personally verified this. I'm just using that one fridge as an example because I'm familiar with and have installed a few of them. And then there's things like the efficiency of the refrigerator's enclosure, wiring/connector and thermal efficiency issues, age of the batteries, etc that can also have some effect on overall consumption.

While I generally agree about not running batteries past 50% of their rated amperage, I don't think this is something which really matters in a case like the occasional boondocker. If you're running them non stop in a golf cart and deep cycling them every day, then yes, there will be lifespan issues. If you are dry camping 3,4,5...8 (whatever) times per year and maybe dipping below that 50% threshold a few times, IMO I just don't think there is much cause for alarm.

Don't get me wrong; I like propane because you can run a fridge easily for a month or more on a single tank. Absorption/3 way fridges come with many more limitations than a compressor firdge though. If you understand these limitations and know how to work within/around them, they're great units (for what they are.) Compressor fridges are far more idiot-proof (for lack of a better term) and better suited to the guy who doesn't always want to be monkeying with things like constantly checking leveling, flame adjustment, troubleshooting pilot lights/regulator issues/ghost in the machine type stuff, LP leaks, switching back and forth from Lp to 12v to 110, back to Lp.... trying to always park towards the shade, etc....

I would keep things really cheap and simple and get a highly insulated cooler, like a Coleman extreme or Igloo equivalent. You can buy mega-tons of ice for the cost of the 12v refrigerator, solar panels, batteries etc... Ice blocks last longer than crushed ice, I always used blocks whenever I could find them when tent camping.

Although, therein lies the rub. Just try to *find* real block ice these days in the U.S.

Many (most?) places seem to have gone to the "fake blocks," which are a block-shaped amalgam of tiny pieces of ice, and are basically useless compared to real blocks.

It's maddening, because yes, an icebox or cooler and block ice is a great, simple solution. But when you can't *get* block ice....

Also, you can store a month's worth of propane, but show me the ice box that can do that. (On boats, even super-insulated, custom-made iceboxes are doing well to get 10 days out of block(s), and that is with 4" or more of insulation, a stepped lid, etc.

I don't mean to sound negative, as an icebox and block ice is my favorite way to go. It's just that I think it would hard to do for long-term boondocking, especially in the U.S, where real ice blocks are going the way of the dodo bird. (Now, in Mexico or Central America, block ice is still king - you can go to a place with a room-sized chunk, and they'll saw off whatever size block you want )

Another way around the problem is to carry fewer foods that require refrigeration, or to preserve them the "old-fashioned" way (such as flipping eggs).

Raya

I have decided It's really not so hard to do without using the refrigerator at all while camping, and using foods that do not require it, as well as not generating 'leftovers'. It does stretch the battery and propane out a loooooong time!

But, I do carry one of those super insulated (and also very small) 30 Qt Galaxy cube coolers that I occasional use if I want to hold fresh milk (instead of powdered) or real orange juice (instead of Tang) and use sparingly for a week or so. They are expensive, but, like tires, worth the extra cost. I am amazed how long some food items, like eggs, can last unrefrigerated.

Agreed completely, John. We as a culture have become so used to refrigeration, that you have to do some research to discover ways to get around it. For example: I've had eggs last for months in the heat of the tropics. You just have to keep air from permeating the shell, which can be accomplished in a number of ways (I flipped the cartons every few days; but you can also coat them with Vaseline or water glass, or boil them briefly).

Also, many many of the products that say "Refrigerate after opening" don't really have to be, if you are careful and use some common sense. Even mayonnaise will keep, so long as you never introduce a contaminated knife or spatula to the jar, and always use a clean one.

Likewise many leftover foods will keep just fine on the stove top overnight. What I would do (when I was living without refrigeration) was, after I was done eating, put the lid on and bring the contents to a boil (or very hot), and then turn off the flame. Then don't touch the lid. The next day, before eating, heat it up again, then serve.

There are many many tricks like this that are nearly forgotten: You can store cheese in oil, wrap limes in foil, etc. etc.

One problem is that foods (such as vegetables, fruits, and eggs) that have already been refrigerated in stores seem to become "dependent," and no longer have their good long-keeping qualities. So you have to seek out farmers or farmer's markets.

I basically did the same as you - I used the icebox (when I had ice) for beverages and for some leftovers, or the ocassional other item; but not for the bulk of my food storage. It's kind of a fun game, really

Raya

OK, here is the schematic for the rig previously mentioned. The grounds for the "load" output have been omitted for the sake of clarity.
Click to view attachment

Raya,
Adding to your comments about storing eggs, I worked at a pub in Germany one summer and we never put the eggs in a cooler. (Irish-American Pub with a chuck wagon in a German village, go figure.) Even at the markets , the eggs were stored or displayed without cooling and often in the aisles.
We have seemed to have lost our ability to survive without gadgets. Somewhere in my vast collection of uncataloged books, I have an excellent book about food prparation and preservation in Britian from the middle ages to the present time. The traditional English meat pie used the heavy crust to keep the meat from being exosed to air, dirt, and other contamination. It was filled with rendered fat or clarified butter to drive out all the air. The crust was discarded like we discard packaging. When properly prepared the pies would stay fresh for several weeks.
Now, I don't plan to junk my frig but it is good to know some alternative ways to preserve and store my food.
Bruce

Something I have never tried but this topic brought it to mind. When I was a young kid I worked on my uncles farm. He would wrap my water bottle with a wet gunney sack before I got on the tractor, and the water always seemed cold. This was in the hot dry prairies, but I have heard of swamp coolers. It might be worth a try some time wrap the cooler in a wet blanket, it would be great if it could save the ice for an extra day.

Our little 1.7 Cubic Foot Frig finally gave up the ghost after 25 years.

After looking around for a year and a half with sticker shock for a new frig, and using good Coleman Extreme 78 Qt coolers with block ice, I am considering doing completely away with the frig...maybe a nice oven in it's place. I am considering getting an Engle or similar cooler for summer trips.

And for those who cannot get block ice easily, just take plastic milk or water jugs, fill them to 90% and freeze. These work very well, and no water sloshing around or needing to be drained in the cooler, or more cold drinking water......

Block ice in our coolers keeps plenty of food cold, and with two coolers, we can take way more refrigerated food than the little old frig would hold. Do miss having popsicles and ice cream sandwiches in camp though...oh well....

I had an Igloo thermoelectric cooler like some have talked about, but it seemed to keep thing cool, but not cold, and battery life was pretty well shortened.


Garo

Judith,
The box you're considering is a good one, this uses the new Danfoss d.c.compressor, it is far better in cooling temps than the thermoelectric/Peltier coolers Peter talks about...While the product has better performance it results in drawing more power wasting more in mechanical energy losses and draws more power as the battery draws down lower...There is a curve in its amp draw vs. available voltage from the battery as with anything.

This tech is put into European trailers now, I have seen two 12v compressor refrigerators in U.S. trailers of late...But my European cousins run out and buy their own version of the adsorbtion ice chest shown in the link below. The reason they do is power drain in the new refrigerator.

I run mine in the car off the cigarette or aux plug on the trip cooling it the day before on A/C at home...Off 115 shore power I use L.P. when camping...At one point I had two chests...One I set to max and the other to minimum...One for meats dairy ect. the other for drinks.

I would stay with a three way, I post a link to one I own...

http://goshopping.thestar.com/shop/product...Id_5428416.html

One of our Canadian customers might help, these are hard to find in the U.S.A...
I set mine on propane with a squat mini propane tank from home depot and its lasts 2 weeks no power at all. (kit can be ordered from the factory to adapt to tank) Coleman made them in the 60s and that one lasted 22 years.

After the investment in all the stuff needed to feed the appetite of the electric one you will own several 3 way models for the price...I have bought mine off Craigs list and eBay, you must search under "3 way" ice chest "u.s.a." or the European and Aussie hits are too many...They are the way to go outside the U.S. why they never caught on here is a puzzle?

Cheers

Harry

Great suggestion Harry!

For those accessable to Canadian Tire it is product # 37-0100-6

For those not, here is a link to the product on the manufactures web site:
http://www.mobicool.com/pages/products/out...cacgas_full.htm

Note the little link at the end of the specs that says the voltages etc. are all set according to the destination country.