Hi Everyone, apologies if this exact scenario has been covered on this forum before. I have an old wooden sailboat that I am converting to use solar/electric for propulsion (a Torqeedo Cruise 6 pod drive with a 48V battery). I also have a Renogy system with a LiFePo4 battery for house loads and two portable 100W panels. Detailed specs below.
I’m trying to figure out the best way to wire up the panels and charge controllers. In a perfect world, I could leave the system untouched and have necessary solar energy go to the battery that needs it most, keeping everything topped off. Obviously the Torqeedo battery is more important.
I’d also like the ability to manually override and force the panels to charge one battery over another if necessary, using a simple switch. Wiring the two solar panels in parallel might slightly exceed the maximum 9A short circuit current for the Torqeedo solar charger. I’m checking with Torqeedo on whether that would be a problem, and if so, I’d probably have to wire in series.
I’m also considering having two completely separate systems, each with their own panel, but of course they would charge much more slowly. Perhaps Victron makes some sort of BMS that can detect charge information for each battery and direct the solar panel output appropriately.
Any advice/insight would be much appreciated!
Solar Panel Output (each)
Max Power at STC: 100W
Short Circuit Current: 5.26A
Optimum Operating Current: 4.96A
Open Circuit Voltage: 23.40V
Optimum Operating Voltage: 20.16V
Efficiency: >23.5%
In parallel: 12v, 10.52A, 200W
In series: 24v, 5.26A, 200W
House Battery
Voltage 12V
Capacity 100Ah
Max charge current 100A
Voltage 12V (Range 10V-14.8V)
5000 cycles 80%DOD, 80%EOL
House Solar Charger
12V/24V/36V/48V auto recognition
Charge current 60A
Load current 20A
Max PV Input voltage 140VDC
Self Consumption .7W-1.2W
Torqeedo Solar Charger
Max module rate current (Imp): 8A
Max module short circuit current (Isc): 9A
Minimum voltage: 12V
Max nominal voltage @ STC (Vmp): 40.8V
Max module open-circuit voltage (Voc): 48V
Max power: 325 Wp
Torqeedo Battery
| Capacity | 5275 Wh | |
|---|---|---|
| Nominal voltage | 44.4 V | |
| Final discharging voltage | 36.0 V | |
| Maximum discharge rate | 200 A | |
| Maximum discharge rate at nominal voltage | 8,800 W |