Appropriate batteries

vancamper
vancamper Registered Users Posts: 2
I'm considering the 650 watt (2 - kyocera 325 watt panel) kit.

What would be the appropriate battery sizes?

I'm looking at maybe 2 - 325 AH 6 volt Crown batteries wired in series for a 12 volt system.

This will be installed on a camper van, so sunlight exposure may not always be optimal. 

Should I consider smaller batteries, that would charge up to full faster?

I'm sure how much electric I'll be running, but I want the biggest solar coverage I can fit on the roof, and this is it.

I'll base my electric usage on available solar power.

Comments

  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    For a 325AH 12V FLA battery bank, your 650W of panel is on the high side. Rule of thumb gives a panel wattage of 325W to match the 12V AH number.
    More panel is OK if the Charge Controller (CC) can be set to limit the charging current to no more than about 40A even when the panels can deliver more.
    SMA SB 3000, old BP panels.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    vancamper said:
    I'm considering the 650 watt (2 - kyocera 325 watt panel) kit.
    <snip>
    This will be installed on a camper van, so sunlight exposure may not always be optimal.
    <snip>
    I'm sure how much electric I'll be running, but I want the biggest solar coverage I can fit on the roof, and this is it.

    Fewer, larger panels (such as those kyocera 325) will definitely cost less than 650 watts of smaller sized panels, but if part of the van is shaded, or part of a panel is shaded, you will harvest more power if you use smaller panels, all combined in parallel.    

    If you do buy smaller panels, consider buying true 12 volt panels and use them with a PWM controller (which is less expensive than an MPPT controller)

    --vtMaps

    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • vancamper
    vancamper Registered Users Posts: 2
    inetdog said:
    For a 325AH 12V FLA battery bank, your 650W of panel is on the high side. Rule of thumb gives a panel wattage of 325W to match the 12V AH number.
    More panel is OK if the Charge Controller (CC) can be set to limit the charging current to no more than about 40A even when the panels can deliver more.
    I see, thanks. So theoretically, I could double the amount of batteries. Or pare the solar panels in half to 1 - 325 watt panel.