Solar on Roof

Originally posted by jato Are you charging 2 deep cycle 6v or 1 or 2 marine 12v batteries?  Also, how long do you estimate it will take to bring either of the above to full charge if you are say at 50% of full charge when you begin?  I find this very interesting.  Thanks.

PV output depends entirely on ensolation.  Under ideal conditions, the 2 panels should deliver about 23 amps.  However, I would count on much less than ideal conditions.  I guess I could count on about 15 amps.  Over a 6 hour day, that would be about 90 amp hours, which represents a bit less than 50% SOC of the 2 6v golf cart batteries.  I know from experience, running a refrigerator and a freezer, water pump, assorted lights and occasional appliances that 2 135 watt panels are sufficient to keep the 2 group 27 marine batteries (storage capacity about 200 amp hours, similar to 2 golf cart batteries) on my boat fully charged.

Nice Job Thank You for the Info 

My opinion, with my fixed solar install, is that I'll still park in the best spot (shady or not) for my trailer and I'll deal with the lower sunlight levels. I believe it evens out, or is even better, in the long run to stick with fixed. My reasons are:

My set up is  for 2 140 watt panels.  Beware that larger panels cannot be shipped UPS and must be shipped truck freight $$$$$$.  There is a good video about the effect of shade on voltage and current at this site https://www.altestore.com/store/solar-panels-c541/  Shading dramatically affects the current output of the panel while minimally affecting the voltage output.  While a shaded panel might produce sufficient amps to keep a well charged battery topped up, it will not charge a discharged battery.  Also, keep in mind that panels are made of multiple solar cells and the way those cells are wired has an impact on susceptibility to shading.
BTW, the folks at altE are very good to deal with.  I've bought several panels from them along with associated equipment.  They have a 100 watt panel for $189.  2 of them could be hinged together to make a suitcase thing that compares favorably to thee Zamp 200 watt set up.  Of course, you do have to add in the cost of a controller and wiring

JandL, very nice idea for a non permanent installation