Portable Solar
With all this talk of portable setups. It's got me thinking of one too. Here's the panels I'm interested in: Two 140W 12V panels. I saw where someone hinged a couple of panels together and put a handl...
Forum Discussion
Mena, beware of having so much battery while camping for a long time. Now that I have over 700AH of battery like you do, and less solar we are back in the soup as far as keeping them charged. 2Oldman went down to four from six batts for this reason ISTR.
You really have to figure it out for your scenario. Camping with no solar, no gen, in winter with lots of AH usage means you need lots of battery to do it all for a long weekend and then recharge at home. You have that.
Now in summer with less usage (no furnace less lights-on time) you take days or weeks to run down to 50% to need a recharge. But by then, how sulfated are you? You could run the gen more, but that is such a waste at the high SOC-low amps range and campground gen time limits can stop you getting full enough too.
So with "some solar" it takes even longer to get down to 50%. More sulfated. So the full- time off- grid guys say to have so much solar per AH capacity so you can get to full every day and not sulfate.
But is there any way to calculate how much solar you would need to do say two weeks off grid and get home in time to do your 100% recharge and not lose anything to sulfation?
I don't know (yet) but I am having a difficult time since getting more battery and less solar, trying to figure out how to last another month without sulfation. I seem to be in neutral buoyancy above 60% and below 90% SOC and can't break out above that with so little solar. OTOH we could do our usage easily with two batts instead of six right now and then the 130w would be enough to get near full every day with some gen kick start as required.
It may be that you should take only two batts along in summer with enough solar and leave the other two at home on a float for a two-weeker, then use all four in winter as before and not count on much solar in that season.
Right now, I am thinking I should take some batts home and put them on the Float charger until this summer session is over or else I could end up with six sulfated batts. I was fine with the solar I had (330w)and just four batts though.
It is an interesting problem and very scenario dependent what to do. Anyway you might want to do some more math on this whole thing.
You really have to figure it out for your scenario. Camping with no solar, no gen, in winter with lots of AH usage means you need lots of battery to do it all for a long weekend and then recharge at home. You have that.
Now in summer with less usage (no furnace less lights-on time) you take days or weeks to run down to 50% to need a recharge. But by then, how sulfated are you? You could run the gen more, but that is such a waste at the high SOC-low amps range and campground gen time limits can stop you getting full enough too.
So with "some solar" it takes even longer to get down to 50%. More sulfated. So the full- time off- grid guys say to have so much solar per AH capacity so you can get to full every day and not sulfate.
But is there any way to calculate how much solar you would need to do say two weeks off grid and get home in time to do your 100% recharge and not lose anything to sulfation?
I don't know (yet) but I am having a difficult time since getting more battery and less solar, trying to figure out how to last another month without sulfation. I seem to be in neutral buoyancy above 60% and below 90% SOC and can't break out above that with so little solar. OTOH we could do our usage easily with two batts instead of six right now and then the 130w would be enough to get near full every day with some gen kick start as required.
It may be that you should take only two batts along in summer with enough solar and leave the other two at home on a float for a two-weeker, then use all four in winter as before and not count on much solar in that season.
Right now, I am thinking I should take some batts home and put them on the Float charger until this summer session is over or else I could end up with six sulfated batts. I was fine with the solar I had (330w)and just four batts though.
It is an interesting problem and very scenario dependent what to do. Anyway you might want to do some more math on this whole thing.
