Solar panel to charge battery

Discussion in 'OnBoard Electronics & Controls' started by seanform, Jul 2, 2007.

  1. seanform
    Joined: Jul 2007
    Posts: 10
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Malta

    seanform Junior Member

    Hello everyone. On my boat I have two batteries,one 100AH and one 125 AH. I would like to keep them (or at least one) constantly on charge with a solar panel. How much current does the solar panel need to be? 10x
  2. Verytricky
    Joined: Oct 2005
    Posts: 248
    Likes: 17, Points: 0, Legacy Rep: 400
    Location: London

    Verytricky Large Member

    Approximately 3w per 100AH unregulated.

    This is to 'hold' a charge, and not to charge a battery.

    Youy need to ensure that your battery can not 'charge' your solar pannel at night, as the losses there would negate putting on a pannel - so use a diode to restrict flow direction. If you exceed around 6w per 100ah you need to look at a regulator that turns off the charge when the battery is full. This assumes a battery in good working order. An old or damaged battery would probably require a higher charge, but dammage will occur if you consistantly overcharge a battery.

    If you are using wind generation you need definately a regulator and a 'dump' to prevent damage to the electrics.
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.