I'm confused, how many batteries do I Need?

[SunEagle]

The other question is if I can add a small wind turbine to augment the panels during night hours and windy cloudy days. The turbine would be the same voltage as the panels. Our location is always windy so I thought this would help with reducing battery bank size by not having to factor in extra cloudy days for my panels. Any thoughts?

Wind turbines require either a lot of height above the tree line or about a 200 clear space around it to capture the wind. And even then you still need about a 25 mph almost continuous wind speed to get close to the output wattage that the turbine is rated.

I have seen some turbines on a lake front property or on a boat but even they may not perform as well as the solar panels.

[Mike90250]

.... Our location is always windy .....

Unless it's windy enough that you have to tie your hat on, it's not suitable for wind. Most people can't live where it's windy enough for good wind power. Sure, many places have usable wind one day out of the week, but the expense and maintenance of a wind turbine, is not often worth it. A few more PV panels will usually be the easiest and best answer. Having a backup generator is also important too.

[organic farmer]

I have a 48vdc 600ah battery bank. It has been very difficult for me to perform equalizing charges on my batteries. That is something that needs to be considered when designing a system.

[Dante3117]

The other question is if I can add a small wind turbine to augment the panels during night hours and windy cloudy days. The turbine would be the same voltage as the panels. Our location is always windy so I thought this would help with reducing battery bank size by not having to factor in extra cloudy days for my panels. Any thoughts?

[Mike90250]

For a full up house without air cond or forced air heat, I have a 48V 800ah bank. Power is expensive

Batteries in series add Volts. and the amps stay the same ( 12V 200ah battery, 4 in series is 48v 200ah)
batteries in parallel add amp hours, 12v 200ah, 4 in parallel = 12v 800ah

[chrisski]

That seems like a lot of batteries. My guess is you're in forklift battery territory.

With your 48 volt, 906 AH, I assume that's daily usage, so you want between two times that 1812 AH to avoid going to 50% depletion, and 2718 AH to go one cloudy day.

906 AH at 48 volts is about 32 golf cart sized 6v FLA batteries. I only mention 6 volt batteries is because my system I have four of those to power my RV a couple of days without a recharge. 6v are light enough at 65 LBS for me to take in and out of my RV as needed.

[Dante3117]

I did a off grid calculator by http://www.altenergydesign.com/offgrid.html and it comes up with 48V 906 battery bank amp-hours with a 3 string set up of 302 per string. When I look at batteries I see flooded lead acid batteries around 200Ah. Does that mean I need just a few batteries for the whole system?