Re: More diversion load stuff
How much excess worth of power do you have per day/month (kWH?).
It would seem if you do not have much power, then the costs would not make it worth the money.
If you have a lot of power, then looking at heat pump type water heater would then be interesting (roughly 2x more heat from same input energy as a resistance heater).
Other way would be a thermal solar array and run the circulation pump with your current DC battery bank (although, a nominal solar PV panels connected to a DC circulation pump would work too.
Back to your setup--you have a fuse/breaker on that line? Resistance heaters in hot water tanks can fail with a dead short.
Also, you should not need to limit yourself to DC rated elements... Get a much larger AC element and derate the wattage by:
You may save some money.
- Element Watts * (Vbatt)^2 / (Velement)^2
20x BP 4175B panels (replacement) + Xantrex GT 3.3 inverter for 3kW Grid Tied system + Honda eu2000i Inverter/Generator for emergency backup.