Best choice to increase run time ?

[12VoltInstalls]

You have six new 200W 12V panels.
You have a bunch of old 12V panels.

What are the watts and VOC numbers for the ‘bunch’ panels? The six new panels VOC?

It is possible that you can configure them to work together on one controller if the numbers work. Using two different arrays will work but it may not be necessary.

 

[GoldenNoodle]

I've got
1] 4 x 80 watt poly Voc 21.6 Isc 5.16 (12 years old)
2] 2 x 150 watt mono Voc 21.5 Isc 9.2 (2 years old)
3] 1 x 245 watt mono Voc 37.26 Isc 8.71 (5 years old)
4] 6 x 200 watt mono Voc 27 Isc 9.6 (new)

I was thinking the polys are prbly not worth keeping for the space they take up and the age ?

2 controllers is not outside the budget. The boss just wants it fixed.

Thanks

 

[12VoltInstalls]

Not ideal, there’s compromise, but the 4 80W sorta could probably live alongside the two 150s ok, into an mppt, but the 245s and 200s won’t match close enough imho. It’s almost like you’d need 3 SCCs-

I’d decide if it were worth it to get charge controllers or more new panels.

 

[GoldenNoodle]

Not ideal, there’s compromise, but the 4 80W sorta could probably live alongside the two 150s ok, into an mppt, but the 245s and 200s won’t match close enough imho. It’s almost like you’d need 3 SCCs-

I’d decide if it were worth it to get charge controllers or more new panels.

Thanks - I'll run that past the boss too.

Is it sensible to have an array facing in two different directions, or is it better to have them on different controllers based on the direction they point? For example the building that the panels are located on now has panels on the South wall and the Wast wall. Right now they are all on one PWM controller.

 

[12VoltInstalls]

s it sensible to have an array facing in two different directions, or is it better to have them on different controllers based on the direction they point?

If you have matched strings on one controller facing two directions you reduce your max amps/watts potential at the - ??? middle 3 hours let’s say - of the day BUT you spread moderately more sun watts over the total light hours of a day.

So basically if you have ongoing loads like a fridge or evening loads you can buffer a full charge to the batteries later in the day meaning your batteries don’t pick up the effort until probably several hours later in the pre-dusk time of day.

Two controllers makes that work, two, which you may benefit from.

I experimented last spring with bi-directional panels facing basically SE and SW and it did very well for me; I was shocked, actually, so much so that I never changed it.

As far as mismatched panels: you can use them. But if you mix unmatched in series-parallel you will limit yourself to the specs of the lower panels: it will work fine, nobody will die, and baby rabbits won’t be ritual sacrificed because you did a weird thing.
People worry about ‘wasting’ power but you have the panels all you need is even a $40 programmable pwm (or two?) or a epever mppt at ~$120 and you’ll get something out of them. But you won’t be committing a moral sin by “wasting” watts…