Help in figuring storage capacity needed.

[medic5678]

Let's say I was hoping to draw an average of 250 watts per hour during an 8 hour period. How many 6v golf cart batteries would I need for this, or is it impractical, period?

[inetdog]

Let's say I was hoping to draw an average of 250 watts per hour during an 8 hour period. How many 6v golf cart batteries would I need for this, or is it impractical, period?

Use the system sizing spreadsheet programs linked in several of the sticky threads in the Off Grid topic area of the Forum.

[Mike90250]

250W x 8 hours = 2064 watt hours
6v x 200ah = 1200 watt hours in a golf cart battery, so to keep drain to less than 50%. you need 4 batteries, I'd wire them into a 24V configuration.
This will be working the batteries pretty hard, nearly a 50% discharge, but you should get 2 years (700 cycles) out of them

[medic5678]

250W x 8 hours = 2064 watt hours
6v x 200ah = 1200 watt hours in a golf cart battery, so to keep drain to less than 50%. you need 4 batteries, I'd wire them into a 24V configuration.
This will be working the batteries pretty hard, nearly a 50% discharge, but you should get 2 years (700 cycles) out of them

Mike, I bought 6 100 watt Renogy monocrystaline panels. I was going to pick up two more batteries (have 4, going with 6), and with a timer, I've found a way to reduce the draw below 1800 watt hours. Since my panels are 12v, should I just wire these up as 12 volts? Not sure why you would go with 24. Thanks.

[Mike90250]

24 volts allows you to wire all batteries in series and that also saves needing an expensive solar combiner box for 12V operation

[medic5678]

24 volts allows you to wire all batteries in series and that also saves needing an expensive solar combiner box for 12V operation

Mike, I'm not sure what you mean by a solar combiner box? My setup is the panels, an mppt controller, the batteries and a charger/inverter (bigger than I really need, for sure). I've also got a renogy tracer meter to monitor the charge on the batteries. So I'll have 6 panels, 6 batteries and two ways to charge the batteries, either solar or my generator.

[Mike90250]

The combiner box is an electrical box with a fuse or circuit breaker for each PV panel. Two parallel strings of PV are OK, but more than 2 and you need a combiner box for safety