2nd hand panels for UK Bluetti AC200MAX?

[indanile]

Hi there, first post and I'm fairly inexperienced with solar stuff so sorry if I say anything stupid...

We have a Bluetti AC200MAX and would like to utilise it to reduce our electric bills as much as possible.

We are therefore looking for the best bang-for-buck solar panels and have seen some 250w panels being sold for £50 each.



The Bluetti can take 900w input, Voc 10-145v max 15A.

These panels are Voc 37.4 and Isc 8.63. Could I do 3s2p giving a total Voc of 112.2 with theoretical max A of 17.26, but face one string SE and one SW?

I have seen a quote from the manufacturer which is attached, and as we are in rainy South Wales we would probably be unlikely to hit max?



One further consideration is that the MC4 connectors have been cut off short so that would need to be dealt with.

I would welcome opinions whether these panels are worth considering, or if I'm barking up the wrong tree ?

Many TIA ??

 

[indanile]

Hi again, I'd be really grateful for any advice on the above. The panels have now been purchased, so I hope we can make it work! I read somewhere about needing a dual input MPPT tho, if the strings are facing different directions?

 

[StuartV]

I'm in sunny South Wales too ??

I've got 2 x 340W panels, but I just move them around the garden throughout the day. I'm currently building a `Solar Sledge' out of a pallet. Put 2 wheelbarrow wheels on 1 end, panel in the middle with a hinge at the bottom, kinda like a deckchair stand, and legs on the opposite end to the wheels. The other panel I'll just lug around till I can build the 2nd sledge.

As for your panels question, have a search through several pages on here, I have seen a few posts about opposite facing arrays.

Hope you find your answer soon ??

 

[indanile]

I'm in sunny South Wales too ??

Ah, from my home town ???

Thank you, will keep researching, it's quite a steep leaving curve and I don't wanna fry my new gadget!

Best of luck with the portable panel idea, we're planning to build a ground mounted frame (or 2) that will be semi-static.

 

[StuartV]

The legs just need painting, then thats 1 done, 1 to go ??

 

[Duodeca]

Shwmae boyos! Interested in this, also in the Welsh valleys and looking at the ac200max.

Looking for fixed panels- What are you using and how is it charging?
Cheers

 

[indanile]

Quick update on this, I just have one string set up at the mo, 3s1p and it's working quite well. Haven't seen more than 553w input out of a maximum 750w, which is a little disappointing in full sun. Also strangely the voltage sometimes shows as 100v (correct) and at other times 44v? Not sure if the MPPT is doing something strange?



Duodeca, did you find panels after?

 

[nikhol]

Quick update on this, I just have one string set up at the mo, 3s1p and it's working quite well. Haven't seen more than 553w input out of a maximum 750w, which is a little disappointing in full sun. Also strangely the voltage sometimes shows as 100v (correct) and at other times 44v? Not sure if the MPPT is doing something strange?

View attachment 106074

Duodeca, did you find panels after?

You should be able to run 3s2p. Be careful with keeping Voltage within range (which you are with 3s), Amperage is not an issue as the MPPT will only pick up, what it can use, the rest is just wasted, so you can run 2p for a total of 3s2p. This way, you should be able frequently to achieve the max input of 900 W.
Are you aware, you can add a charge enhancer/adapter to the ac200max and add another 500 W solar input through the AC charging port?
Cheers from sunny Denmark

 

[indanile]

You should be able to run 3s2p. Be careful with keeping Voltage within range (which you are with 3s), Amperage is not an issue as the MPPT will only pick up, what it can use, the rest is just wasted, so you can run 2p for a total of 3s2p. This way, you should be able frequently to achieve the max input of 900 W.
Are you aware, you can add a charge enhancer/adapter to the ac200max and add another 500 W solar input through the AC charging port?
Cheers from sunny Denmark

Thank you for your reply! We ended up using 3 separate structures (eastish, southish, westish) with 3 panels on each, so 3s3p using the aforementioned panels. That gives us around 500w even on a cloudy day and easily hits its max of 920w when the sun is out.

Yes, I've read about the D050s charging enhancer and may well get one, although the voltage input limit of 60v makes it difficult to find suitable panels to get the 500w. Need a battery first tho, to store the extra!

 

[nikhol]

Thank you for your reply! We ended up using 3 separate structures (eastish, southish, westish) with 3 panels on each, so 3s3p using the aforementioned panels. That gives us around 500w even on a cloudy day and easily hits its max of 920w when the sun is out.

Yes, I've read about the D050s charging enhancer and may well get one, although the voltage input limit of 60v makes it difficult to find suitable panels to get the 500w. Need a battery first tho, to store the extra!

That's a great idea with three separate structures, as panels are the least expensive on a PV system these days!

 

[eMptyBox]

You should be able to run 3s2p. Be careful with keeping Voltage within range (which you are with 3s), Amperage is not an issue as the MPPT will only pick up, what it can use, the rest is just wasted, so you can run 2p for a total of 3s2p. This way, you should be able frequently to achieve the max input of 900 W.
Are you aware, you can add a charge enhancer/adapter to the ac200max and add another 500 W solar input through the AC charging port?
Cheers from sunny Denmark

Clipping kills!


More than likely produce extra heat because that energy has to go somewhere. Overall best to minimalize clipping for efficiency.