by TECHSTAR on DECEMBER 3, 2010 - 18 Comments in ENERGY, OFF-GRID 101
FROM YAHOO ANSWERS:
Here’s my setup: 24V battery bank (6x4V Rolls-Surrette deep cycles in series) connected to my wind and solar charge controllers as well as an inverter for my house, all in a shed about 60′ from the house. I also have a 24V panel in my garage directly connected (through a breaker) to my batteries over 100′ away at this point (voltage drop is minimal because I sized the wires right).
What I’d like to be able to do is use my vehicle as a back-up generator for when my batteries get too low (e.g. 22V) by parking it in the garage (with the door open of course) near the panel and applying a charging voltage to the panel from the vehicle. My thought is to connect a 400W inverter (I already have one in the back of my Tacoma) to a 15A, 24V battery charger and put it on a 15A breaker in my panel. Theoretically, this will raise the system voltage to the 28V charging voltage of the battery charger, which will fill the batteries. The first question is, will this work as I expect? Secondly, what if the well pump kicks on pulling 3000W? Will that trip the breaker on the charger even though the batteries, which might otherwise be at 22V, have sufficient amps to handle it? I’m not sure of the preference of where power will be pulled from. Will the battery charger be the go-to source of all household power because it’s at a higher voltage? Or will the charger merely put out as much power as it feels like and the loads won’t affect it? If the charger is going to trip its circuit every time there’s a load bigger than 15A on the system overall, then there’s no point in doing this. Otherwise, if the charger will just do its thing oblivious to anything else, then this would be a great solution for emergency battery charging for my house. I.e. I’d be jump-starting my house with my truck!