Re: Solar Battery Charger
Reply #50 –
Mark,
Don't over complicate things too much. Our 900 watts @24 volts on the roof have put out as much as 710 watts (50 amps at 13.8 volts into storage) but that is not typical. We have put over 5KW in a single day into storage but a realistic daily average is closer to 2 KW. We are in a high level of tree coverage now and are less than that but still more than the refrigerator uses.
Figure out what your needs are and then size everything accordingly figuring on maybe 25% overall, year around efficiency.
I never even considered any tilting mechanism, powered or manual. I am not getting on the roof to tilt manual ones (too much risk) and motors and wiring and controls seem way too complex and costly for this application.
My 300 watt panels have 12" long mounts, one at each corner on the side held in place with 3M VHB tape, 1.5"x12", no screws. I had the mounts made with an appropriate angle to match the roof curve. They are sealed with 3M 4000UV adhesive sealant. 72 sq inches of tape x 91 psi in tension gives me over 6500 lbs of holding power per panel. I cleaned the roof and brackets with acetone, then denatured alcohol and then used a 3M cleaner and adhesion enhancer and then stuck things together. It is rock solid.
Lots of help from Alan at Bay Marine Supply on sizing, Victron components, fuses, switches and the rest of the parts you need.