What panels to chose for 12kW Inverter

[Bossman253]

What kind of Solar panels choose for 12kW Deye Inverter?
I would need about 5kW of power for now. I will expand system in next year.
I was thinking about Bifacial with double glass panels
Such as, 650W or 700W Double Glass Bifacial HJT
Panels will be on tracker in mountains. They will not be on roof.
I am in EU, any recommendations ?

 

[OffGridForGood]

Go with what is available at a good price in your area Bossman,
get the specs and double check the VOC and IMP for the panels against the Deye PV inputs - likely no issue with a 12k inverter and 5kW of PV - a single input will likely work.
Maybe you already have a couple panels in mind, since 650's and 700's are not that common - yet?
Only thing to consider with large panels - will you have a way to lift these up to the tracker you are planning? ie 700 W panels with double glass are heavy.

 

[Brett V]

You need to consider your mppt voltage range and how many panels you can put in series. You need enough voltage to turn on charging but allow for Voc on your coldest morning or risk burning out the mppt with over voltage.

From my own experience, I have a Growatt SPF 12000t DVM. It has two charge controller inputs, each with a maximum voltage of 150 volts. A few years ago, I bought ten 325 watt panels. I have them in a 2S 5P configuration and they work great. Under load they hang around 65 volts which is just enough to keep the mppt happy. They are 72 cell panels. This year I jumped on a good price for eight 410 watt panels without thinking it through. They’re 60 cell panels and 2S only gets to 56 - 58 volts…not enough to keep the mppt happy. I tried 4S and they worked wonderfully, but the first cold morning below freezing I get, calculations show the voltage will exceed 165 volts and that exceeds the upper voltage limit. So my only choice to use these panels with my equipment is 3S. Having 8 panels, that meant I could only use 6 of them. I was lucky enough to source 1 more panel so I can do a 3S 3P arrangement. I had already purchased a pair of eG4 Brightmount racks which hold 4 panels each and had to get creative with finding a spot to mount that 9th panel.

The moral of the story is I could have saved myself a lot of extra work by checking ALL the specifications of the panels before buying and not just focusing on watts. Do the math ahead of time and go shopping with a clear understanding of what will work. Your inverter likely has a higher upper voltage limit and your numbers will be very different from mine, but it’s still important to plan ahead.

 

[Bossman253]

You need to consider your mppt voltage range and how many panels you can put in series. You need enough voltage to turn on charging but allow for Voc on your coldest morning or risk burning out the mppt with over voltage.

From my own experience, I have a Growatt SPF 12000t DVM. It has two charge controller inputs, each with a maximum voltage of 150 volts. A few years ago, I bought ten 325 watt panels. I have them in a 2S 5P configuration and they work great. Under load they hang around 65 volts which is just enough to keep the mppt happy. They are 72 cell panels. This year I jumped on a good price for eight 410 watt panels without thinking it through. They’re 60 cell panels and 2S only gets to 56 - 58 volts…not enough to keep the mppt happy. I tried 4S and they worked wonderfully, but the first cold morning below freezing I get, calculations show the voltage will exceed 165 volts and that exceeds the upper voltage limit. So my only choice to use these panels with my equipment is 3S. Having 8 panels, that meant I could only use 6 of them. I was lucky enough to source 1 more panel so I can do a 3S 3P arrangement. I had already purchased a pair of eG4 Brightmount racks which hold 4 panels each and had to get creative with finding a spot to mount that 9th panel.

The moral of the story is I could have saved myself a lot of extra

Thanks for your time and effort to answer me.

 

[Bossman253]

Is there anyone could help me with the numbers ?, i am bit in the fog, right before i choose solar panels.

Actual system specs:
Eve 316ah MB31 3,2v 16cells
Deye Inverter SUN-12K-SG04LP3-EU
Chargeverter 5kw (generator behind it)

 

[Bop]

5kw of them is 7 in series, if the panel Voc is 50.13v (assuming you are talking about the G12 series 700w bifacials) each, then their Voc at STC is 350.9v...
For the Sun-12k-SG04LP-3-EU, the minimum startup voltage is 160v, the MPPT range is 200v-650v, and their recommended voltage is 550v...

It will work, it's not in its best operating range (550v)- 10 panels with the specs of the G12/700W in series will be a better match to its input... but yes it will work on 7 series panels/5kw on the one single string (-DON'T try and split the string- it's too small for that- all in series with your 7 panels, all on the one MPPT input!!!
With a 17.67A Isc, well under the Sun's 34A limit (its rated at up to a total of 15.6kw- so your 5kw is well under its limits...

Are you planning on wiring this up yourself???- because it is a 3 phase inverter, and to put it mildly- not a job for a beginner....

Instruction manual
I'd want to sit down and reread that manual several times myself before tackling that install myself lol

 

[Brett V]

@Bop Thank you for giving the OP more information. He had asked another question and sent me a PM asking for help, but I'm traveling for work at the moment and only able to reply on my phone.

 

[Bossman253]

5kw of them is 7 in series, if the panel Voc is 50.13v (assuming you are talking about the G12 series 700w bifacials) each, then their Voc at STC is 350.9v...
For the Sun-12k-SG04LP-3-EU, the minimum startup voltage is 160v, the MPPT range is 200v-650v, and their recommended voltage is 550v...

It will work, it's not in its best operating range (550v)- 10 panels with the specs of the G12/700W in series will be a better match to its input... but yes it will work on 7 series panels/5kw on the one single string (-DON'T try and split the string- it's too small for that- all in series with your 7 panels, all on the one MPPT input!!!
With a 17.67A Isc, well under the Sun's 34A limit (its rated at up to a total of 15.6kw- so your 5kw is well under its limits...

Are you planning on wiring this up yourself???- because it is a 3 phase inverter, and to put it mildly- not a job for a beginner....

Instruction manual
I'd want to sit down and reread that manual several times myself before tackling that install myself lol

Yes i am planing to wire that myself but for sure i will use all way remote support that i can get.

So you are saying that 10 panels of G12 700w will be better in terms of starting MPPT?, how about winter ?, if there is not much sun, how i can calculate if mppt will start when there is less sun ?.

And When we will got full sun, i am much below inverter maximal input so it iw safe, that is what i understood.

Is there a possibility that you can help me to guide in this process privately ?, i am a bit in situation that we have already not much time to cover all that to have power there (mountains), we are totally offgrid atm. Ofcourse i can pay for your effort.

Thanks in advance, your post already helps a lot, thanks

 

[Bop]

I'm a bit far away lol- Australia (the place with kangaroos, not the other Austria lol)

10 panels will get it up into the better band for the MPPT (which will improve its efficiency ie more daily generated power- more so than just the 'added power' it gets from the extra panels, the efficiency of the MPPT circuits up higher as well...)

The MPPT circuits in it start at 160v (regardless of temp or time of year- thats internal to the inverters circuitry)

You are mixing the wattage with the voltage- the wattage isn't 'that' important and won't damage the inverter (indeed quite a few people deliberately 'overpanel' ie go past the maximum the inverters charge controller can use in good weather, in order to get better performance in poor/cloudy conditions... which can be done with many inverters completely safely...- the charge controller inside the inverter will only accept as much power as it can use- its the Voc (voltage open circuit) that varies with temperature that is what causes problems when the panels are cold- every degree C the temp drops, the voltage rises (in the right (WRONG) conditions 10%-15% can be seen... and if you are already right at that PVmax limit with your combined Voc voltage- well smoke comes out...)

They have an absolute 'do not go past here or bad things happen' limit of 800v, they recommend going no higher than 650, the best performance is at 550v. and it starts at 160v...


https://www.deyeinverter.com/product/hybrid-inverter-1/sun5-6-8-10-12ksg04lp3.html

(I have the opposite problem- in summer, we get air temps in excess of 40C, often 45C, and the panel temps rise to 80C or more- thats when my power levels drop- dramatically- summer here is no better than winter in terms of power production!!! my 250w panels are down below 200w by those temps...)

 

[Bossman253]

I had to change my panels to 615w model, can you tell me if 7pcs will be okay for now ?, i will try to go with more but there is no more in stock.

Panels i have chosen are G12 615w
There is spec

https://panele-sloneczne.com/wp-content/uploads/Datasheet-Huasun-HJT-615W-Bifacial-Double-Glass.pdf

Thanks in advance

 

[Bossman253]

You need to consider your mppt voltage range and how many panels you can put in series. You need enough voltage to turn on charging but allow for Voc on your coldest morning or risk burning out the mppt with over voltage.

From my own experience, I have a Growatt SPF 12000t DVM. It has two charge controller inputs, each with a maximum voltage of 150 volts. A few years ago, I bought ten 325 watt panels. I have them in a 2S 5P configuration and they work great. Under load they hang around 65 volts which is just enough to keep the mppt happy. They are 72 cell panels. This year I jumped on a good price for eight 410 watt panels without thinking it through. They’re 60 cell panels and 2S only gets to 56 - 58 volts…not enough to keep the mppt happy. I tried 4S and they worked wonderfully, but the first cold morning below freezing I get, calculations show the voltage will exceed 165 volts and that exceeds the upper voltage limit. So my only choice to use these panels with my equipment is 3S. Having 8 panels, that meant I could only use 6 of them. I was lucky enough to source 1 more panel so I can do a 3S 3P arrangement. I had already purchased a pair of eG4 Brightmount racks which hold 4 panels each and had to get creative with finding a spot to mount that 9th panel.

The moral of the story is I could have saved myself a lot of extra work by checking ALL the specifications of the panels before buying and not just focusing on watts. Do the math ahead of time and go shopping with a clear understanding of what will work. Your inverter likely has a higher upper voltage limit and your numbers will be very different from mine, but it’s still important to plan ahead.

What will you say for 7 pcs of chose

https://panele-sloneczne.com/wp-content/uploads/Datasheet-Huasun-HJT-615W-Bifacial-Double-Glass.pdf

 

[Bossman253]

it seems that isc for g12 is to high for Deye.
Isc is max 17A and working current till 13A. Panels has nearly 19A Isc it will be bad.

Any other bifacial double glass 600+ watt recomendations ?

 

[shadowmaker]

I'm have same 3-phase Deye(s) and have Bluesun 700W bifacials in 16S (11,1kWp) configuration for MPPT1 and GCL 550W monos in 14S configuration (7,7kWp) for MPPT2.

16S for MPPT1 is bit too much voltage (~750V @STC) for cold mornings/evenings here as we can go down to -40C, but I was told it was ok from Deye engineer, although I get 15-30 high voltage alerts every year as voltage creeps over 800V sometimes. Otherwise it is working so nicely that I'm willing to risk it.

MPPT2 is overpaneled as it can use only 6kW. This is nice as weather rarely is optimal.