New Panels... Parallel or series? Parallel I think...

[bigjoncoop]

Hey,

I've been building large lithium batteries for quite some time now for myself, friends, and clients. (1kWh-15kWh)

At home I have a 10kWh 24v battery and a 6000w LF Split Phase inverter. Which I normally just used for emergency backup power during Hurricane Season etc...

I have a PowMr MPPT Solar Charge Controller rated at 60a @160v Max.

Yesterday I purchased 3- 130w panels.
There rated at 57.4v @2.25a

I'm assuming I should string the panels in parallel so I'll have 57.4v @ 7.25a.

Correct?

My goal obviously is to get the most out of the 3 panels to charge my battery as fast as possible...

I do realize that these 3 panels are no where near enough to for the size battery I have.

Below is the datasheet of the panels.

 

[Tecnodave]

At that high of VOC, yes all in parallel.

You say thin film.....do you know the specific cell type? I have some First Solar CdTe panels but the watts per square for made them occupy too much rack space. They are still kicking around.

That is very low efficiency.......9.09%..........my Panasonic HIT panels are 20% efficiency

 

[Jim Burrow]

With a Vmmp of 57.4 volts and Immp of 2.265 amps, you have enough voltage. So like Techovave said, go all Parallel with your panels. In theory, that will give you around 57 volts and rounding off, 6 amps for around 342 watts. Note though that you probably would get those numbers in real life.

For my panels, I do get the Vmmp voltage, but the Immp current is way short in real life. There is a lot of variables involved in getting the manufactures readings that we don't have a lot of control over.

 

[bigjoncoop]

@Tecnodave @Jim Burrow

Hey guys thanks for getting back to me so quick. All right so parallel it is...

Yeah, those panels are quite old I believe the data sheet said 2012

I found them locally on Facebook Marketplace yesterday. He was selling them for $50 a piece and they are brand new. Old new stock. He had two full pallets of them.

I figured for $50ea I might as well grab a couple. The issue with them is that they're very large and heavy

 

[Bossrox]

A solar charger doesn't care if you feed it panels in series or parallel, just so long as the the panel voltage is above what's required to charge the batts & below the chargers max voltage input. Your fine with your set up but you'd save the extra wire runs by running the panels in series & that would still keep you below the max charger input voltage & give you the same charging output.

 

[Bossrox]

A solar charger doesn't care if you feed it panels in series or parallel, just so long as the the panel voltage is above what's required to charge the batts & below the chargers max voltage input. Your fine with your set up but you'd save the extra wire runs by running the panels in series & that would still keep you below the max charger input voltage & give you the same charging output.

1 other thing, running panels in parallel if joined at the panels to a single wire going to the charger will require a higher capacity wire than running in series. Panels in series can use the same size wire feeding the chargers as a single panel. Amps stays the same in series, it multiplies in parallel.

 

[rhino]

but you'd save the extra wire runs by running the panels in series & that would still keep you below the max charger input voltage & give you the same charging output.

He'd be over the voltage limit of that charge controller putting 3 of them in series. Voc is 70.9V per panel.

 

[Bossrox]

Ah, yeah, don't know how I missed that, must of been thinking of my own panels, not used to seeing low watt panels with that high of an output volts. Disregard that last post.

 

[Tecnodave]

Bossrocks,

That is not common in monocrystalline or polycrystalline panel, OP has Cadium Telluride, they typically have 100 or more “cell bands” not common at all in residential, they have an advantage in very large scale “power plant“ installations and they are used there, commonly frameless all glass panels. I have a few First Solar CdTe panels.