re: #145 Dangerman

Solid-state relays have a voltage drop since they’re semiconductor devices, not contacts. If you’re scavenging for joules then use really good-quality contactors and relays, don’t cheap out. Over-spec them, if you’re switching 40A currents regularly then buy 80A or 100A rated devices (doof-car audio gear often has decent high-current switching devices at reasonable prices if you don’t mind pointless gold-plating here and there).

Wiring, make it as thick as you can bend and as short as you can route them. If you can, convert to higher voltages as close to the solar panels as you can since low voltages and high currents means greater losses in the wires.