On Thu, 14 Oct 2010 05:24:56 -0500, Rick Morel
wrote:

Adding it all up, the total is:

[ 94.5 Amp Hours per day ]

So you're looking at basically 2 days with your batteries.

With LED anchor and inside lighting,

[ 68 Amp Hours per day ] Quite a difference.

Basically almost 3 days.

Remember you don't want to totally kill your batteries.

Good point.

If you want normal life from your inverter batts it is important to
limit the discharge level to less than 50% (about 11.7 volts when
under load). The net result is that you need twice as many amp-hours
as your energy budget, perhaps more if your recharge time is limited.
It take quite a while to bring the charge level back to a full 100%
because the acceptance rate tapers off once you are above about 80%.
A good design point for A-H capacity is 3 times your energy budget.

AGM batteries have a higher charge acceptance rate but cost about
twice as much. They are worthwhile however if limited by size and/or
weight. Gel cells have good acceptance rates also but are easily
damaged by higher charging voltages. Not worth the risk in my opinion
since AGMs are coming down in price.