Solar Battery Charger

The battery load of the AC will be about 150 amps at 12 volts. This means for one hour of AC you will need 300 amp hours of usable battery. OR 6 Golf cart (series parallel) or 6 group 31 batteries. That weight would be in the nearly 500#--for one hour! The solar panels to do that charge (~5.5 amp hours per 100 watt 12 volt panel: about 2500 watts of solar panels... It is not going to happen.
 
I should have explained what I wanted to do with the solar generator I know it would not power my AC for a long time (overnight )
My friend who has a Cutwater 24 has 4 group 27 batteries(system comes with 2 AGM batteries 230 amp hours )so 6 group 27's and we were wondering if we could use the solar generator to get his mermaid AC system to get his boat cool for an hour trip and then an hour trip back from our Cruise club island that we own here in Naples
Then if it works on his boat try it on mine with upgrade batteries ??
Also thinking of upgrading solar generator to 2500 watts or more depending on cost $$
 
Well, here is the physics/math answer to your question:

Group 27s whether FLA or AGMs typically store 75 AHs of power each. So 6*75= 450 AHs. But discharging below 50% reduces battery life so you should not use more than 225 AHs. 225*12= 2,700 watt hours available in that case.

Your friend has a 12,000 BTU/hr A/C system as I recall. These typically draw 12 amps or 120*12= 2,440 watts. If run continuously and you will if you are just cooling down, then you can power your A/C for about an hour.

Then it will take at least 2,700 watt hours to recharge those batteries fully for the next time. Solar panels generally can produce 4 times their wattage rating in watt hours for a sunny day. So it will take about 700 watts of panels to recharge them.

If you want to run the A/C all night which will probably be at 50% duty cycle then it will take about 4-5 times the battery capacity and 4-5 times the solar panel wattage to do that.

David
 
Whoops, a little bad math above :cry:

The A/C will draw 1,440 watts, not 2,440. So you can power the A/C for a bit less than two hours and it will take 2-3 times the current battery capacity to run all night and 2-3 times as much solar to recharge them.

David
 
Yes I think this is doable running the AC for 2 hour trip there and back on batteries and Solar and engine running Thanks
 
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