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Nah I did not get my shorts in a knot. Just want to make it clear there is no payback in batteries. Next order of biz: I will say a prayer tonight for your wife.
OK let's talk about what you have to work with, and how to best utilize it. I don't care what you use it for, just tell the the best least painful (wallet) way to get the most bang for your buck$.
OK you have 560 watts of panels. Or two 280 watt GT panels rated at Vmp = 31.9 and Imp = 8.78 amps. This gives you two battery voltage options of 12 or 24 volts. It is not a candidate for 48 volts because with both panels wired in series is 63 volts which falls short of 70 volt minimum requirement for a 48 volt battery charger. The answer you have to make is what battery voltage to use?. Normally I would say HIGHER VOLTAGE option is always right. There are some exceptions and one of those is RV Compatibility. Huge after market of 12 volt RV gadgets and gizmos for sale. Use something other than 12 volts, and you loose that perk. But if money talks, then the higher voltage 24 volts is the right voltage for you. Here is the wallet deal on battery voltage. Does not effect battery investment cost one little bit. Takes the exact same batteries and quantity.
Where it hits your wallet is Charge Controllers and now let's talk about that. Most important decesion you have. First get over it, you must use a MPPT Controller. If you used 12 volt battery you turn your 560 watts into 210 watts of panels. At 24 volts same lousy 210 watts. So here is the money question. If you run 12 volt battery will require a 40 amp MPPT controller for $350. Run 24 volt battery and all you need is a 20 amp $200 controller. Another difference with MPPT controllers you actually get 560 watts out of a 560 watt system.
Last word batteries. You already have 4 6-volt batteries. Experiment and learn with those. They will work for 12 or 24 volt with your panels just fine with the right charge controller. Then when the time comes replace them:
For 12 volts min = 340 AH, max = 500 AH. somewhere in that range.
For 24 volts min = 170 AH, max = 250 AH
I suspect your golf cart batteries are 220 AH right? At 12 volts that is 440 AH and at 24 volts is 220 AH. It works. If you got it use it, perfect fit.
Do that and your batteries can support up to 1 Kwh usable power per day. But hold your horses. Your panels may or may not be able to generate that much in a day. Depends on how the panels are installed, location, and time of year.
So here is what I would recommend and I think most here will agree is as good as it gets for you.
Panel Wattage = 560 watts
24 volt 220 AH batteries, or 4 good 6-volt 225 AH batteries like Trojan T-105. Can also be 12 volt with 40 amp CC.
Morningstar PS-MPPT-25 25 Amp Charge Controller. Good to 700 watt input @ 24 volts, 350 watts @ 12 volt battery
1000 Watt 24 volt TSW Inverter.
That would be an optimum matched system. With T-105 batteries at 24 volts can easily run a 1500 watt inverter. with proper care, attention to details with cabling requirements and workmanship. Having said that it does not mean you have to run a 1500 watt Inverter. It just means NO LARGER THAN 1500 watts. Always run as small of an Inverter as you can. Unless you gotta a microwave oven or toaster to run, 1000 watts may still be to much.
Edit Note:
Technically it is possible with the two panels could be forced to use as 48 volts. But doing so comes with consequences, limitations, and expense. Running at 63 volts, and you loose some of the advantage of using a MPPT Controller efficiency. At 48 volt battery magic happens inside MPPT controllers at 70 volts and higher input, they wake up at 95% or more efficiency. You defeat the purpose.
At 48 volts you are not going to find any modes for 10 amps worth having. 48 volt systems are used for higher power systems of greater than 2000 watts. Means they do not make 48 volt controllers for lower power so you are now looking at a 30 to 40 amp model for $400. You can get 20 amps at 24 volts for $200.
Regardless if you ggo with 12 or 24 volts, use a MPPT controller, and wire your panels in series. Make sure the CC you buy can handle 90 Voc minimum.
OK let's talk about what you have to work with, and how to best utilize it. I don't care what you use it for, just tell the the best least painful (wallet) way to get the most bang for your buck$.
OK you have 560 watts of panels. Or two 280 watt GT panels rated at Vmp = 31.9 and Imp = 8.78 amps. This gives you two battery voltage options of 12 or 24 volts. It is not a candidate for 48 volts because with both panels wired in series is 63 volts which falls short of 70 volt minimum requirement for a 48 volt battery charger. The answer you have to make is what battery voltage to use?. Normally I would say HIGHER VOLTAGE option is always right. There are some exceptions and one of those is RV Compatibility. Huge after market of 12 volt RV gadgets and gizmos for sale. Use something other than 12 volts, and you loose that perk. But if money talks, then the higher voltage 24 volts is the right voltage for you. Here is the wallet deal on battery voltage. Does not effect battery investment cost one little bit. Takes the exact same batteries and quantity.
Where it hits your wallet is Charge Controllers and now let's talk about that. Most important decesion you have. First get over it, you must use a MPPT Controller. If you used 12 volt battery you turn your 560 watts into 210 watts of panels. At 24 volts same lousy 210 watts. So here is the money question. If you run 12 volt battery will require a 40 amp MPPT controller for $350. Run 24 volt battery and all you need is a 20 amp $200 controller. Another difference with MPPT controllers you actually get 560 watts out of a 560 watt system.
Last word batteries. You already have 4 6-volt batteries. Experiment and learn with those. They will work for 12 or 24 volt with your panels just fine with the right charge controller. Then when the time comes replace them:
For 12 volts min = 340 AH, max = 500 AH. somewhere in that range.
For 24 volts min = 170 AH, max = 250 AH
I suspect your golf cart batteries are 220 AH right? At 12 volts that is 440 AH and at 24 volts is 220 AH. It works. If you got it use it, perfect fit.
Do that and your batteries can support up to 1 Kwh usable power per day. But hold your horses. Your panels may or may not be able to generate that much in a day. Depends on how the panels are installed, location, and time of year.
So here is what I would recommend and I think most here will agree is as good as it gets for you.
Panel Wattage = 560 watts
24 volt 220 AH batteries, or 4 good 6-volt 225 AH batteries like Trojan T-105. Can also be 12 volt with 40 amp CC.
Morningstar PS-MPPT-25 25 Amp Charge Controller. Good to 700 watt input @ 24 volts, 350 watts @ 12 volt battery
1000 Watt 24 volt TSW Inverter.
That would be an optimum matched system. With T-105 batteries at 24 volts can easily run a 1500 watt inverter. with proper care, attention to details with cabling requirements and workmanship. Having said that it does not mean you have to run a 1500 watt Inverter. It just means NO LARGER THAN 1500 watts. Always run as small of an Inverter as you can. Unless you gotta a microwave oven or toaster to run, 1000 watts may still be to much.
Edit Note:
Technically it is possible with the two panels could be forced to use as 48 volts. But doing so comes with consequences, limitations, and expense. Running at 63 volts, and you loose some of the advantage of using a MPPT Controller efficiency. At 48 volt battery magic happens inside MPPT controllers at 70 volts and higher input, they wake up at 95% or more efficiency. You defeat the purpose.
At 48 volts you are not going to find any modes for 10 amps worth having. 48 volt systems are used for higher power systems of greater than 2000 watts. Means they do not make 48 volt controllers for lower power so you are now looking at a 30 to 40 amp model for $400. You can get 20 amps at 24 volts for $200.
Regardless if you ggo with 12 or 24 volts, use a MPPT controller, and wire your panels in series. Make sure the CC you buy can handle 90 Voc minimum.
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