Having suffered a neck injury, it has become difficult to lift anything 25 lbs or more & attempting to remove my batteries from the tongue of my TT is difficult at best. Currently, I keep them in the garage with a trickle charger, but am considering solar in the future so that they can stay on the tongue year round. I have 2-GC batts on the coach & it is off site & no power is available. I have no hands on knowledge of solar, but it seems to be my best alternative under the circumstances. This is what I'm considering. Any suggestions and /or opinions on this set-up & equipment to be used would be appreciated. I would like to keep cost to a minimum. I do have a disconnect switch & there will not be any load on the batteries.Solartec S01PC-15 - PanelSunforce 60031 - Controller

Go with a 100 watt panel as a minimum to be worth the effort.Yes it is a bit more money but 15w is too small IMO.

Yes, you can get a solar battery maintainer that will do the job, but for almost the same money you can get "some solar" that will do that plus help while camping if you ever camp off grid.You can get portable (or installed on roof for more money for the installation cost), but then you might have problems with shifting the portable with the neck problem, don't know.IMO do anything to avoid the rip-off hardware store low watt "solar" at $5 per watt compared with getting a real solar set from a real solar dealer at $2 per watt or less.

A 10A controller is enough for 150 watts, maybe 200 watts of solar. About 2 years ago I bought a 75W panel and a Morningstar SG-4 controller from solarblvd.com for about $125 total. I rigged the setup to plug into the trailer's 12v pigtail (that goes to the tug) and left the panel unmounted. My controller is outside, too, but it is made for that. For storage off site, a mounted panel and indoor-mount controller probably makes more sense to deter theft. Shop around a bit, you can get far more solar than that 15W and it will be money well spent. It will help you on those trips when you find a great place to spend a day or two but there's no shore power.

My goal is maintenance only during storage. I am not concerned with power when I'm dry camping. Those needs are already met with my generator & would like to avoid installing any permanent panel on the TT roof or carrying a portable panel & setting it up each time. I am only wanting to avoid removing the batteries while in storage, but yet, keeping them charged. I understand the controller is overkill for what I want to do & can handle larger panels, but it seems to have very good reviews.

If you go with 15w panel you can skip the controller on a pair of GC2.

Solar as battery maintenance during storage - opinions

36 Replies

Dakota98
Explorer
Dec 16, 2014
BillyW wrote:
Not sure what part of Idaho you're in. Definitely more sun down south, but up in the Coeur d'Alene area, I'm pretty sure 15 watts would do little. A little snow followed by an extended cold snap, and that panel will deliver next to zero. I guess if you have good permanent southern exposure... I kind of like Pianotuna's recommendation of a larger panel secured vertically.

My trailer has two 75 watt panels on the roof that provide plenty of camping power and enough winter maintenance for my two 6v batteries with only a couple hours of direct sunlight daily max (if I'm very lucky). When the snow gets deep and sticks around, I plug in the shore power.

Hi Billy,

I'm in the Boise area. You're up there with a close friend of mine in Post Falls, Mr. Casey - retired high school principal.
TurnThePage
Explorer
Dec 16, 2014
Not sure what part of Idaho you're in. Definitely more sun down south, but up in the Coeur d'Alene area, I'm pretty sure 15 watts would do little. A little snow followed by an extended cold snap, and that panel will deliver next to zero. I guess if you have good permanent southern exposure... I kind of like Pianotuna's recommendation of a larger panel secured vertically.

My trailer has two 75 watt panels on the roof that provide plenty of camping power and enough winter maintenance for my two 6v batteries with only a couple hours of direct sunlight daily max (if I'm very lucky). When the snow gets deep and sticks around, I plug in the shore power.
BFL13
Explorer II
Dec 16, 2014
pianotuna wrote:
Hi,

If you insist on going portable, do the 2 70 watt units and add a hinge. That way the two glass surfaces will be protected when storing the unit.

Really 140 watts is the bare minimum for 232 amp-hours of battery bank.

My panel instructions state that the white backing is just as delicate as the blue front, and do not prop it up using the white backing part, only use the frame.

Since the OP is only really intending to use his solar for storage, he can get the one panel and play with it when camping off grid-- if he ever does camp off grid. Once he ever does, he will become addicted to solar and then he can get more. No need to jump in at the deep end.
pianotuna
Nomad III
Dec 15, 2014
Hi,

If you insist on going portable, do the 2 70 watt units and add a hinge. That way the two glass surfaces will be protected when storing the unit.

Really 140 watts is the bare minimum for 232 amp-hours of battery bank.
BFL13
Explorer II
Dec 15, 2014
Dakota98 wrote:
OK, All you guys have got me re-thinking this.

With the single purpose still in mind, I'm leaning towards maybe a 100 watt portable panel & going ahead with the controller in that case. Who knows, maybe I would use it when dry camping & it would then serve dual duty. :h

From my experience, it is way more fun to have the amps reading on the controller's display plus some other good info, than to have the basic controller with just some lights to show how the recharge is going. You can see the difference immediately when you aim the panel more towards the sun for instance.

So I recommend the Solar30 on eBay for $35 instead of the $15 jobs that you could get that would do ok too, but have no display. I got mine in about three weeks by snail mail. It works great. Niner has one two (or maybe more :) )
Dakota98
Explorer
Dec 15, 2014
MEXICOWANDERER wrote:
On a small rig using an absorbed glass mat battery and a chassis disconnect switch is viable. <1% month self discharge, a six months storage = a 94% charged battery. No wires, no panel, no wiring, just the cost of the new AGM battery. At 20F an AGM battery self-discharges around .6% per month.

I like the idea of AGM's, but these GC's only have one season on them, so that will have to wait until they become deceased.
Dakota98
Explorer
Dec 15, 2014
OK, All you guys have got me re-thinking this.

With the single purpose still in mind, I'm leaning towards maybe a 100 watt portable panel & going ahead with the controller in that case. Who knows, maybe I would use it when dry camping & it would then serve dual duty. :h
Dakota98
Explorer
Dec 15, 2014
jrnymn7 wrote:
Yes, buying solar across the border is hardly worth it, for us Canucks. But for you, it's a pretty reasonable price, it seems.

Besides, couldn't you use a sack of potatoes to maintain those batts?

With a nice baked spud & chili over it, I could probably develop enough gas to power the coach without batteries, if only I could figure out how to store it long term. :B
MEXICOWANDERER
Explorer
Dec 15, 2014
On a small rig using an absorbed glass mat battery and a chassis disconnect switch is viable. <1% month self discharge, a six months storage = a 94% charged battery. No wires, no panel, no wiring, just the cost of the new AGM battery. At 20F an AGM battery self-discharges around .6% per month.
jrnymn7
Explorer
Dec 15, 2014
Yes, buying solar across the border is hardly worth it, for us Canucks. But for you, it's a pretty reasonable price, it seems.

Besides, couldn't you use a sack of potatoes to maintain those batts?