UPG 250 amp hour agm batteries

When yachties debated residential fridge issue, there was not even much of a debate. To the question "can I?" there was a short answer - "yes, if you only sail from marina to marina". Or, in Rv lingo - camping with hookups only. (Or - with tons of batteries and again, only doing short passages from hookup to the next hookup).

Well, he wants to run a gennny every morning...

Alnot,

This quote had me scratching my head because when I was researching an all electric fridge for our unit, NovaKool was one of the manufacturers of which there are many, who use the Danfoss compressor and their main customers were marine and now more and more RV's. So if the yachting group preffered absorbtion fridges, where were these electric fridges going?

Went over to the Yachting forum and there are many threads on installation of the marine fridge and owners talking about the danger perceived or otherwise of propane pooling in the bilge with a potential for explosion, fires in absorbtion fridges(old technology), and the fact that to run efficiently, the absorbtion fridge needs to be fairly level when in use. That doesnt sound too compadible to sailing.

In reality, yachts are just RV's on water so why would they be any different than land based rigs when they boondock?. Most of the boats who posted about their marine installs were generating power to their batteries from on board generators, solar and wind. My observations on sail boats is that the great majority are in the sub and tropics not the Gulf of Alaska,which means warmth and sun and wind, great ways to charge batteries.

One other thing that came up was the reason that the marine fridges cost more/cuft than residential fridges was that they are more efficient, do not require an invertor,have better compressors which in the end will save you money.Buy cheap, buy twice. The recommendations from experience yachties was not to go with a residential fridge unless you had access to shore power 24/7.

Our system is simple. 260 days dry camping, 2 hours generator time, 3 campsites with hookups, fridge/freezer ran 24/7. In your words," our system will work well in areas where there is no propane". Looks like it works well in all areas.

Dave





Desception Sound, BC. Rained all week on and off.Alone again. July 1/12

Crosscheck, it's not that "all electric fridges don't work unless you are hooked up". It's that 120V fridge won't work unless you have a lot of batteries and means to charge them, or you are hooked up.

Yours is 7.5 cu.ft 12V, and even though it's big for a 12V model, it's an equivalent of a small office fridge - not a residential fridge. With an added bonus of not using an inverter, its energy efficiency is boosted by another 10-15%. The net result is 50-70 AH in 24 hours compared to 90-110 AH of residential unit. This comes at a steep price, 4-5 times higher than a bigger volume residential unit from big box stores. For a longterm boondocking away from propane sources 12V fridge and solar is the way to go, yes. 7.5 cu.ft with 300W looks underpowered for cloudy locations like BC. Your batteries will stay undercharged, dropping to 50% or below and never reaching 100% (you might think it's 100, while it's not), without a generator. But it will work.

Include this...

For folks with HYDROMETERPHOBIA, AGM is the hot setup.

tplife wrote:

... on my 6th year with an Optima Blue-Top.
...

Darn! I was hoping my Optimas would die sooner than that. I want more AHs, but am wary of mixing new AGMs with them. Maybe my Deka will die. :)

HTH;
John

+1 on the AGM benefits, including typically lasting twice as long as a lead-acid equivalent. Glad I don't have to lug around a battery box, no issues with unvented storage, no holes in my jeans,deep discharge and full recovery going strong on my 6th year with an Optima Blue-Top. Would never go back to old 20th-century lead-acids in my campsite or my Harley!

crosscheck wrote:

...
Powell Forest canoe circuit. Powell River, BC. July/12. Spent one week early July where every day was cloudy or had rain. Still drycamped/boondocked without running genny.


Dave

I was was a Winter Texan in an RV resort WITH shore power and guess who was having ice cream sundaes and banana splits when the absorption fridge folks went without. I did share!

HTH;
John

The key to all electric fridges is storage, if you plan to do any or a lot of dry/boondocking camping. What type(wet or AGM) is your choice depending on your pocket book,time spent on maintenance. inside/outside etc. How you keep your storage full is up to you,(alternator, genny, solar, wind, biosolids= hahaha).

Our 7.5cuft AC/DC fridge/freezer takes the equivilent of a 60w lightbulb when cycling. The cycling times depend on inside temps, door openings. 4 6V AGM batteries with 330W solar have allowed us to dry camp 260 days in the last 2years with less than 5 hours of genny time, and we have lots of other electrical gadjets that we use.Some of these times dry camping have been at times on the west coast when it rained or had heavy cloud cover much of the time.

It is interesting that the naysayers who tell you that all electric fridges don't work unless you are hooked up full time have never tryed them. "They won't work in a Louisiana swamp in July because the draw on the batteries in the heat is too great or Yellowknife in November because of to much battery draw from the furnace fan." Who wants to RV in extreme conditions and be a prisoner in their rig?

Spent 1 week in Catalina SP in March in overflow. Lots of gennies being run by rigs who had traditional absorbtion fridges. Guess who had ice cold beer every day and didn't have to rely on his generator?



Powell Forest canoe circuit. Powell River, BC. July/12. Spent one week early July where every day was cloudy or had rain. Still drycamped/boondocked without running genny.

Dave

full_mosey wrote:
You should find draws around 60-90AHs daily at normal room temperatures. That was my experience with a dorm fridge.

Or more, with an office size fridge 8-9 cu.ft, and more yet, with a small residential fridge 12+ cu.ft. 110 W he says... let's say 30% cycle at room temp, this is 8 hours run in 24 hours, or 880 WH = 88 AH. Considering 360W draw on start-up, with his fridge I wouldn't be surprised to see 100 Ah in 24 period. 40 Ah overnight maybe. Then there is a furnace in winter or fans in summer, lights, microwave, who knows what else... 70 or 90 AH total overnight...

When yachties debated residential fridge issue, there was not even much of a debate. To the question "can I?" there was a short answer - "yes, if you only sail from marina to marina". Or, in Rv lingo - camping with hookups only. (Or - with tons of batteries and again, only doing short passages from hookup to the next hookup).

Well, he wants to run a gennny every morning...

dave17352 wrote:
\
I bought a killowatt from harbor freight (I think that's what it is called) My 10.3 cubic foot refer draws about 3 amps on start up and about 110 watts while running. So far I have only used a couple hundred watts over 10 hours at night. I love that little meter it is super handy shows total watts used as well as instant watt measurement. Shows your amp draw and voltage.

That KAW is going to prove very useful. :)

The total Watts used over time is actually called WattHours, there is a difference. A 200W light draws 200Watts, if run for 2Hours you say you used 400WH.

You can roughly translate your 200WH into battery AHs by dividing the 200WH by 10.

The AHs drawn will be influenced greatly by the ambient temperature around your fridge. You should find draws around 60-90AHs daily at normal room temperatures. That was my experience with a dorm fridge.

HTH;
John

MNtundraRet wrote:
Dave:

How many amps is the Residential Refer. drawing on a 1-hour duty cycle? Have you checked the amps being drawn from the battery-bank with a clamp-meter? They will be 10 times the 120v,ac draw when using 12v, dc.

I just purchased a new 1000 watt (2000 surge) inverter (10 year old 400 watt inverter just died) for my HD TV and 2nd amplifier (plus other temp. uses). The inverter does show "wattage" and "amps" under load, but "watt's" readout is inaccurate under 200 watts (per specs.). For the TV drawing less the 25 watts reading is zero. The reason I used the clamp-meter on the battery cable.

The reason I ask is that it looks like you expect to use the refer. 24/7 over a weekend, along with all other normal 12v needs. Using just two 75AH batteries does not seem doable, especially for having batteries hold up long-term.

P.S. I missed the comment about the generator, so you should be okay.

I would love to dump the RV refer. when they come out with energy efficient compressor refers. Many new units coming out with residential, but manufacturer's expect you be camped on an electric site, not boon-dogging.

I bought a killowatt from harbor freight (I think that's what it is called) My 10.3 cubic foot refer draws about 3 amps on start up and about 110 watts while running. So far I have only used a couple hundred watts over 10 hours at night. I love that little meter it is super handy shows total watts used as well as instant watt measurement. Shows your amp draw and voltage.