I have been struggling with wanting to upgrade my battery system in my MH (Sunseeker 3100SS) but I am confused by the solar argument. Most people I camp with have an 80w-100w solar panel that they claim works great for trickle charging their battery throughout the day. My current system is very simple, 2 6volt Interstate GC2 batteries wired together resulting in a 12v system with 225 amps available (stock converter, no inverter) with a battery disconnect switch.
The obvious question people will ask is "what do you primarily use your batteries for?" The answer is, not much. We use them for the basics: lights, shower, furnace, water pump. We boondock exclusively (maybe 10 times a season) and I'd like to be able to watch a movie occasionally but will probably never bring along my satellite dish to watch TV. We have a generator and I use it to make cofee and "recharge" the batteries (which is terribly inefficient--because of the stock converter).
I'm thinking about upgrading my battery system to four 6volt batteries which would result in a 12v system with 450 amps. The alternative is to add a solar panel/controller to try and capture back *some* amps throughout the day. There are differing opinions on how many amps will be collected through solar panels (which adds to my confusion).
Here's a high-level cost breakdown:
- (2) 6volt Interstate batteries (GC2)
$300/pair (added to my existing two batteries).
- (2) Solar Cynergy 100 Watt 12 Volt Solar Panel
- (1) Morning Star SSD-25RM controller
Basically, it appears that the solar cost is roughly $420 vs. battery cost of $300. I'm not sure that cost of solar power can be justified if I'm capturing back, say 10 amps/day (that is a total guess?) while the additional batteries will double my amps.
Note: I would have to make significant modifications to my battery tray in order to accommodate four 6volt batteries. I am not including the cost of that for comparison since I intend to upgrade that part of my RV regardless of this debate. There would be additional cost to upgrade my compartment from a two battery system to a four battery system but I don't know how much.
Any thoughts/comments would be much appreciated.