Stupid battery and solar questions
I figure I am going to have a lot of them, so I better put all in one thread :B. My situation: - I mainly want solar for running residential freezer and fridge, maybe also for charging my shave ...
Forum Discussion
Naio wrote:
Whoops, I meant 40 VOLTS. Will edit the post :)
Answer is still the same - figure out total array wattage you need. With 300W and less it makes more sense using PWM, with 400W and more - MPPT. Eventually the choice will depend on both wattage and budget.
Array made of 40V panels (38-40V units are called nominal 24V), with 12V bank, will ONLY work with MPPT. There were people here using PWM with 24V panels because they've bought PWM before the panels and then found some free used 24V panels, ending up with 50% loss of efficiency. "Normally" :) PWM with 24V panels is not a good idea, and neither is planning controller before the panels.
PS: revisiting the OP #1, - even without MW, a very rough estimate would be more than 500W array and more than 300 AH bank to be able to run items that you mentioned without daily "fix" of generator, on most days. I would max the array up to the limit, in your case. 400W peak load sounds scary, though it doesn't tell much in itself. You need to estimate daily WH or AH, not W.
Btw, 600W microwave draws upwards of 900W on high setting.
