Is my thinking on electrical corect?

[nature lover]

I have read so much on solar and electricity that I sometimes seem more confused than educated.    I want to add a solar panel someday ($?) but I need a fridge for meds right away.  So I am thinking of a 200 Ah battery connected to alternator for charging (with solenoid) then adding a 12 volt (cig litter) plug and an inline fuse and plugging the fridge into it.   Don't need an inverter only 12 volt.  don't need a charge controller as no panel yet.  My fans and lights are on rechargeable batteries and I have plenty to last until I am "plugged in" again.   I"ll add another battery, panel, charge controller and inverter as cash allows.  Comments please.

 

[user 423]

That would work but if you didn't drive much the battery could get depleted (too much,too often).

My 105ah FLA batt weighs 59 lbs. and the 100ah AGM weighs 63 lbs.

What kind is the 200ah you're considering?

 

[nature lover]

I am planning on the NPP NPD12-200Ah Rechargeable Deep Cycle 4D SLA 12V 200Ah - not the cheapest but not the most expensive. Has good reviews. Link below. Weight is a draw back at 1138 lbs, but 2 100 ah would be similar.


https://www.amazon.com/dp/B01J94RBD...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

[Tony's Dream]

I think you mean 138 pounds. A battery that weighs 1/2 ton is really heavy.

I would have to ask, how many amps will your frig pull? Most pull a lot, so your batter would exhaust in about 4-5 hours.

 

[Dakotalee]

Yea...youre ...right.....i would add this. Its going to take alot of driving to keep the battery charged. More than you probably will do. Charging from the alternator is more a supplement for solar.

I would suggest this.... If your only load on the battery is going to be the fridge, try to calculate if you can get through a night on a 100ah battery. Take that extra money and get the cheapest charge controller that reasonably works and try to get 100w panel. 2 if possible. Or a larger panel. Look for used ones. Then add more solar and batteries as you go. That would be the route I would go.

Running off the alternator with a solenoid only cost about 25$. I got my solenoid for 15$ on amazon plus how much wires cost.

 

[jacqueg]

I think you mean 138 pounds.  A battery that weighs 1/2 ton is really heavy.  

I would have to ask, how many amps will your frig pull?  Most pull a lot, so your batter would exhaust in about 4-5 hours.

Depends on the fridge. My 40 qt Alpicool uses 43w / 3 amps on 12v.

 

[Dakotalee]

My Engel sr70 uses 2.7@ 12v

 

[nature lover]

You are right, the battery is 138 lbs. I have parkinson's and often hit the wrong keys or the same one several times. If you take notice my posts are usually edited. I ordered An iceco 20 - it only runs 1/2 the time in hot weather and less in colder weather. I forget the figure but will look it up and get back. I appreciate all the input.

 

[nature lover]

I looked it up - the iceco 20 runs from 2.5 to 5 - am I right in thinking that is amps per hour? If I am there would be 100 amps available from the battery, since it only runs 30 min out of the hour that is 2.5 a at the max. - which makes the battery last at least 40 hours before it needs charged. When I am near 110 I have a heavy duty charger for the house battery and will plug the fridge into 110 also and during the first month I will be staying closer home area where 110 is available Of course when I am driving the fridge will be plugged into the van battery. This will be only for a month so until I get $ for panel and controller - inverter will come latter. So am I missing something? I am pretty dense. = stupid.

 

[user 423]

IMHO I wouldn't get that big of a battery. You can get two 100ah AGM batteries for about the same price that would be a lot easier to handle.

If you bought one AGM you would have $200 left over towards solar or a small generator.

 

[Dakotalee]

Don't discharge the batteries past 50% you will damage them. So a 100ah battery will only have 50ah of useable energy

 

[highdesertranger]

also remember for maximum battery longevity the battery must be recharged every single day. so that means you must drive every single day until the battery is FULLY charged. as someone else mentioned alternator charging is a supplement, it is not a primary charge source. highdesertranger

 

[nature lover]

I was not aware that the battery should be charged every day. I thought it was every cycle, get down to almost half, how ever long that takes and then charge again. I will never drive enough in a dqy to charge from alternator, can't aford that gas. I( have to rethink it all. Going with a smaller battery and spending the savings on solar seems to be an answer. Is my thinking and math on Ah comsumption right?

 

[user 423]

^
If the average consumption of the fridge is 2.5 amps then 50% of a 100ah battery will give you about 20 hours of operation.

If you had a combination of solar, charging while driving and sometimes using a charger, you may be able to keep it charged properly.

Lots of variables though. Ambient temps the fridge has to deal with, insulation on the fridge, how much you drive, how much actual charging you get from solar and how often you can hook up to shore power.

(Below is just an example. I'm no expert and most of my experience is with FLA car starting batteries. Some of which lasted 6 years because I always kept them maintained):

--If the battery isn't charged properly then it may die in 2 years.
--If it's kept charged correctly then it might last 4 years.
--If it dies in 2 years then you're spending $7.50/mo on batteries (using a $180 AGM as example).
--If it last 4 years then you're only spending $3.75/mo.

--And I guess if you really messed up and the batt died in one year, then it's $15/mo.

YMMV

 

[nature lover]

My eyes are too bad to drive in the rain and on those days the solar would not work so it ain't as easy as it looks. The desert "rats" in Arizona got that solar thing better than we eastern forest dwellers.

 

[user 423]

Yes but desert dwellers have their own, different problems.

96 where I'm at.

Trying to finish work on my van during the day in the blazing sun is impossible. No shade to be had.

 

[Dakotalee]

I'm in PA. It can work. I recently upgraded my panels and charge controller. I have 500 watts of panels and a charge controller from my old system.. I don't know if you would be interested?

 

[tx2sturgis]

96 where I'm at.

Trying to finish work on my van during the day in the blazing sun is impossible. No shade to be had.

Shade?....I hear tell of this....'shade'....

Somehow it seems to be related to ...what are they called? Oh yeah....'trees'....

 

[nature lover]

Dakotalee - i WOULD BE INTERESTED. nORMAL QUESTIONS LIKE WHY DID YOU REPLACE THEM - BRAND NAMES AND NUMBERS AND PRICE YOU ARE ASKING. wHAT PART OF pa? - HAVE WE MET HERE BEFORE? YOU CAN PM ME - THANK YOU

 

[nature lover]

tx2sturgis - come to PA and we will show you what shade is. Or just watch Jamie's latest video.