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Skip Gundlach wrote:
I'm obviously missing a great deal of intelligence here. I had thought we'd properly sized our bank and input sources to allow for our anticipated usages. Obviously I was mistaken; I need a large-frame alternator and the appropriate drive components, in order to only bring my bank to 90%. Wet cell batteries are a very mature technology. The rules for them are very simple. 1) If you want to consume 200AH/day, you must generate 250AH/day of replacement energy. You can play all kind of regulator games, but in the end, the overall average replacement rate is about 15% of the bank capacity or in this case, 15%(750)=112.5A. The minimum recharge time will be: 250/112.5=2.2 hours. How you choose to get it done is your business, but the above rules define the task. Solar: For an engineering estimate, use a 2ftx4ft,80W panel which translates into 10W/sq ft. Derate 50% for dirt, clouds, angle of attack, etc, thus 5W/sq ft. As a year around average use 12 hours/day, thus 12hours(5W/sq ft))=60 watt-hours/sq ft/day. 60watt-hours/12volts=5amp-hours/sq ft/day. To generate 250AH of solar you need 250/5=50sq ft or at least 7 2ftx4ft panels. Probably not going to happen unless you build a hard bimini so you have a place to plant your solar garden. That's why alternators like the L/N 4800/4805 family exist. Modest size, only 145/165 output depending on model, but either deliver in excess of 100A at 2,000 alternator. Ya pays ya money, ya takes ya pick. Lew |