grizz272
frozen tundra, WI
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2 friends of mine have purchased new campers that have 12dc only refrigerator in them. They both came with 50 watt solar panel on the roof. They are figuring on boondocking 4 or more days with only 2 batteries to keep the fridges running.
Is this possible?
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lancewgurel
Spokane Valley WA
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eric1514
AZ ID
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I suppose it would depend on the size of the batteries and the specs of the fridge, but normally, I would say no. More information would help answer your question.
2006 Dynamax Isata IE 250
420 Ah batteries
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JimK-NY
NY
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A 50 watt panel will generate up to about 25 AH/day. That maximum is only possible on a clear day with no obstructions and in mid Summer with the sun directly overhead on the panel.
I have a small (4 cuft), efficient Nova Kool compressor refrigerator. It pulls about 2.3 amps when running. At roughly 70 degrees it runs a minimum of about 10 hours a day for 23 AH. If the ambient temps are higher, or the refrigerator is opened numerous times, or if you add any items that need to be cooled down, the compressor is going to run much longer and can easily eat up 40 or more AH/day.
I would recommend at least 200-300 watts of solar in order to generate sufficient power for the refrigerator, lights, water pump, and minimal use of a furnace. The rule of thumb also requires roughly 200-300 AHs of battery bank. I have 270 watts and still need to use a generator for cloudy days, when not parked in direct sun, and for Fall-Spring use when the sun is lower in the sky and less intense.
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Lwiddis
Near Mammoth, California
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If your buddys’ batteries are wet, “how long will the batteries last” is a bad idea. Wet batteries need full recharging daily for maximum life. If the batteries are lithium, that’s a whole different ballgame. Regardless of battery type, fifty watts of solar won’t be sufficient. Start with one solar watt per battery amp hour.
Winnebago 2101DS TT & 2020 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AMP Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad
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Lwiddis
Near Mammoth, California
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Additionally, adding solar panels isn’t difficult but make sure the wire from the panels to the controller and the controller itself are rated for the added watts.
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wa8yxm
Davison Michigan (East of Flint)
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There are a few different types of 12 volt fridges.
1: Absorption cooling units SUCK power like crazy (About 300-400 watts for proper cooling 12 volt may cut it down to around 250 or about 20 amps or so they often have 25 amp fuses.
Standard compressor 100-200 watts
High efficacy (What I call Danfoss class. Danfoss is one of the makers of the compressors used. there are others) around 30-50 watts DOOR CLOSED (opening the door can add another 20-30 watts for the blanged light)
There is one more type but .. First not that good. and 2nd Eats power.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times
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CA Traveler
The Western States
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My guess is they won't make 4 days. However key information is missing in order for anyone to make an informed gess. Like battery capacity, refer type and power usage and temperature. And then their usage of the refer and all other 12V power usage.
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Bob
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bikendan
Goodyear, Arizona
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grizz272 wrote:2 friends of mine have purchased new campers that have 12dc only refrigerator in them. They both came with 50 watt solar panel on the roof. They are figuring on boondocking 4 or more days with only 2 batteries to keep the fridges running.
Is this possible?
Not without upgrading the solar wattage and battery bank. 50 watts is insufficient and their two batteries are probably the typical cheap dual-purpose marine batteries.
Dan- Firefighter, Retired">, Shawn- Musician/Entrepreneur">, Zoe- Faithful Golden Retriever(RIP">), 2014 Ford F150 3.5 EcoboostMax Tow pkg, 2016 PrimeTime TracerAIR 255 w/4pt Equalizer and 5 Mtn. bikes and 2 Road bikes
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goducks10
There
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They won't make it 2 nights with just 2 batteries and 50W of solar. Sounds like they've been listening to their RV sales person too much. Just the angle of the sun and a few clouds or even an overcast day will make that 50W panel almost useless.
I'm sure their RV's have a Zamp solar side port since most all seem to these days. So I would advise them to get a 100W or higher portable solar panel and use that port.
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