Watts needed
I have read where folks suggest any where from 1 to 2 watts of solar per ah of battery. My question, is this based on battery rating (ie 215 AH) or is it based on useable amp hours(105)? All reply...
Forum Discussion
With two flooded lead acid 125Ah batteries being charged by two 100W solar panels the draw from the fridge and freezer would take the batteries down to 50% SOc after two days and no actual use of the fridge. With a 3-way fridge the juice to power the fridge electronics is very small and with our prior camper going for weeks with only two 100W panels was not a problem and we did not take a generator.
When I replaced the lead batteries with lithium phosphate ones of equal capacity I found that the solar was better able to keep up with demand as the controller could provide a higher level of charge and the batteries charge much faster and so make better use of available light.
I want as much battery capacity as will fit in the RV and as much in the way of solar production on the roof as I can find space for on the roof. Panels are cheap at roughly $115 for each 100 Watts of panel output. By far the most expensive aspect of adding solar is doing the wiring runs inside the RV.
When I replaced the lead batteries with lithium phosphate ones of equal capacity I found that the solar was better able to keep up with demand as the controller could provide a higher level of charge and the batteries charge much faster and so make better use of available light.
I want as much battery capacity as will fit in the RV and as much in the way of solar production on the roof as I can find space for on the roof. Panels are cheap at roughly $115 for each 100 Watts of panel output. By far the most expensive aspect of adding solar is doing the wiring runs inside the RV.
