Might add a third panel
So I need to move my solar panels around to add a Fantastic Vent over the bed. I always figured I'd add one more panel so I could have 450 watts of Solar. The reason I'd like to add one more panel i...
Forum Discussion
What furnace has to do with the discussion, is that it draws 12V :). In the OP low-use and solar-only scenario, furnace is probably the biggest item, and it does have zero-current alternatives, as posted.
Off-grid with solar only (no generator), when solar is small like the OP's, mandates shallow cycling. Even 450W might not bring it back to 97% if they start from 70% in the morning and the day is not super-bright. So, bigger battery will be a bonus, bringing the morning charge level higher.
With the addition of FanTastic fan this item will become #1 in summer, drawing as much AH as the winter furnace, and in Ca they might need fan in the night as well. This is where bigger battery comes handy again.
Forget about "enough current to charge 4*6" - the objective is staying above 80% where high current is not important. This shallow-cycle objective is applicable only to low-use low-latitude scenarios like the one discussed here. OTH, if you run 110V appliances or it's not the South, you start in the morning from less than 60% and then high current (relatively to battery size) becomes important.
The 3rd panel would help on a dark day, feeding in few extra AH, so that the evening charge level won't drop too much and you'll start (hopefully) from close to 80% in the morning.
Off-grid with solar only (no generator), when solar is small like the OP's, mandates shallow cycling. Even 450W might not bring it back to 97% if they start from 70% in the morning and the day is not super-bright. So, bigger battery will be a bonus, bringing the morning charge level higher.
With the addition of FanTastic fan this item will become #1 in summer, drawing as much AH as the winter furnace, and in Ca they might need fan in the night as well. This is where bigger battery comes handy again.
Forget about "enough current to charge 4*6" - the objective is staying above 80% where high current is not important. This shallow-cycle objective is applicable only to low-use low-latitude scenarios like the one discussed here. OTH, if you run 110V appliances or it's not the South, you start in the morning from less than 60% and then high current (relatively to battery size) becomes important.
The 3rd panel would help on a dark day, feeding in few extra AH, so that the evening charge level won't drop too much and you'll start (hopefully) from close to 80% in the morning.
