phmccartney
New Member
- Joined
- Jul 19, 2022
- Messages
- 1
I have an electric sailboat currently powered by a 48 volt bank of traditional golf cart batteries. I am planning to upgrade my battery bank to LifePo4, either 2 or 3 banks of 12 volt 100ah batteries. I want to add solar to charge them, but un-shaded space on a 35 foot sailboat is limited. Due to the position of the backstay and the extent of the boom, my optimal configuration would be two 60 cell panels (typically 66" x 40"). Here is my question. Most of the 60 cell panels i see, have a Voc of around 40 volts and Vmp of around 33 volts, and are rated by some as a "20 volt panel" (eg Trina Solar TSM-DD06M.05-325) rather than a "24 volt panel". It not clear to me if two of these in series would generate enough volts to charge a 48 volt LiFePO4 battery back. I know that a 600 watt system wont generate many amps and may take several days to recharge the system if deeply discharged, but my question is whether they can generate enough volts to charge at all or if i should try hold out for panels that are capable of a higher Vmp, even if it means having to ship them rather than find a local pick up? I plan to go with a Victron 48 volt solar charger which will not have boost capability, so i think I need to be sure the panels will have enough voltage even in hot weather. Ive looked at options for using more panels in series, but all the configurations I've tried seem to increase weight aloft and result in lower total watts due to the constraints of placement on my boat. Thanks for any advice.
Peter
Peter