Community Forums

2InAlabama · 06-14-2016, 02:25 PM

This winter we will be storing our coach in a storage lot in Tucson, AZ with no hookups. How much solar charging capability will I need to keep both sets of batteries (3 chassis, 3 house) plus keep the residential fridge running?

cb1000rider · 06-14-2016, 03:01 PM

That's hard to answer because it depends on a number of factors:
1) How many days you're going to go without sunlight (cloudy)?
2) What is the current amp draw - and average amp draw in a 24 hour period?
3) What is the current storage capacity of your batteries?
4) Where are you (average days of sunlight per year)? How well oriented are your panels?

Off the top of my head, I'd say that you're out of luck if it's cloudy for 24 hours. It's unlikely that 3 batteries would retain enough charge to run the residential fridge for that long...

twinboat · 06-14-2016, 03:12 PM

I left my 7 c.f. residential fridge on for 3 months. I have 675 watts of solar and 800 AH of battery.

The boat was in Florida in the summer. I wasn't.

I checked my data history on my TS controller. It showed It reached float charge most days.

Just a point of reference.

vsheetz · 06-14-2016, 03:14 PM

Is this long term or short term storage? I ask because wondering why the need to keep the residential refrigerator operating? With the RR no matter how much solar several days of continuous no/low sun days can come up short on battery capacity.

100-200w of panels for battery maintenance. Preferably 200 due to low winter sun in AZ and assuming flat mounting.

Add another couple hundred watts for the residential refrigerator. Again assuming low winter sun in AZ and flat mounting.

2InAlabama · 06-14-2016, 07:26 PM

I would have the panels mounted so they could be elevated to take advantage of the sun's angle. So I guess I will just leave the fridge off for the winter months. So 2 140 watt panels should keep the batteries up. Those expensive batteries are my main concern.

Gary RVRoamer · 06-15-2016, 07:41 AM

Assuming everything that is possible to turn off is "off", and the rig is in the sun most days (not under roof or trees), I would guess 25-30 watts would do it. That would produce about 1.5 amps in full sun, a reasonable "trickle" charge for the batteries. In the Northern US during the winter, when sun is lower and skies often cloudy, I would want more, maybe 50-80 watts.

There are many variables, so this is strictly a WAG.