High Voltage Solar Panels

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Kroks

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Hi fellow humans.

A follow up on a previous thread I crated HERE

As with everyone, desperation have now kicked in. Previously I was only planning on installing a inverter in my Baldwin apartment, with no panels and was looking for a "silent" inverter. Well none are really suitable.

The plan now is to get approval for a ZOZO type hut in my garden (didn't want to do this to not loose space, but hey....POWER)
In there I will house a inverter and battery/s. This will also allow me to attach solar panels to the roof. With the size of the ZOZO I can install 2 panels at most (std 2m x 1m panels).
Because of the the Vmp on the solar, I can only go for a 3 KW (24V) unit. The best in that is the the small 3 KW Growatt units.
The drawback is that it is only a 3 KW unit, and more than that the batteries are insanely expensive, and the selection rather limited.
Hubble AM-2 is around 20K each, I see other options but they are all "off brand".
So for 5 KW storage I will need to spend R40K just on the batteries. The equivalent 54V battery starts at just over R 22 K for a different brand, and R30 k for the Hubble.

So to get the same storage I will need to spend more on a 3KW system in total.

I have been looking for other options, getting 4 small panels with a similar footprint of the generic 45V panels. But by the time you get a small enough panel, they swop to 24V, defeating the intent.

I found CNBM 6P-325 325W High Voltage Poly Solar Panel, with a Vmp of 74V. So 2 can get me to 148V and that will allow for a 5KW 48V inverter and in turn a "cheaper" battery.
Yes, there is the potential problem of a broken panel, and I'll loose all solar, but no problem buying a extra unit and keep it in storage (in the new ZOZO I have to install)
Does anyone have any other ideas? my general load is small, about 300 W constant. I would prefer to have 640W panels, but sacrificing generating power for a 5KW inverter is a trade off I am willing to make.

EDIT: I check CNBM's website, and they don't have this panel listed.... so will have to investigate more, but please and other ideas will be greatly appreciated.
 
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The voltage of the panels is probably not tied to the voltage of the inverter. The MPPT should convert the panel voltage to a suitable voltage for the inverter/batteries.
 
You don't really need a Zozo if space is a problem, you can get a mounting structure to mount the panels and still have the space underneath, unless the motivation for the Zozo is purely for housing the inverter and batteries.

I you do end up going the Zozo route you can position it to mount up to 4 panels on either side of the roof, in landscape form, or if it's small remove the roof completely and build your own roof with solar panels, they can overlap on all sides as long as they are properly supported.
 
Not sure what your budget is but the 3.6kw sunsynk and between 3 and 5 330v high voltage panels should work quite well.

www.sunsynk.org

Sunsynk | Smart Energy Solutions

Sunsynk solar energy products and solutions.
www.sunsynk.org www.sunsynk.org

Also no need to keep spare panels around you can just replace the broken one.

You can also install the sunsynk inverters outside. So maybe against the apartments outside wall with the panels on the roof.
 
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B-1 said:
Not sure what your budget is but the 3.6kw sunsynk and between 3 and 5 330v high voltage panels should work quite well.

www.sunsynk.org

Sunsynk | Smart Energy Solutions

Sunsynk solar energy products and solutions.
www.sunsynk.org www.sunsynk.org

Also no need to keep spare panels around you can just replace the broken one.
Click to expand...
I would live a Sunsync, but it also has the 100v starting range on the MTTP. The Growatt starts at 30v.
 
You don't need to buy a high voltage panel to use big inverter

You string panels in series
ie 4 panels with a vmp of 35v would give you a vmp of 140v

So even that may be too much
Inverter dependant

ie some 5kw inverters have a mppt of 145v voc and an mppt range of 60-115

Though they are more scarce lately. As all see the benefit of single series string less fuses thinner wires
And i think better bad weather performance

Others have a 100-450v range
Getting 4 panels with a voc of around 50v would put you smack dead in the middle

Keep in mind to use the rule of thumb and don't exceed 80% of the voc
 
TheChamp said:
You don't really need a Zozo if space is a problem, you can get a mounting structure to mount the panels and still have the space underneath, unless the motivation for the Zozo is purely for housing the inverter and batteries.

I you do end up going the Zozo route you can position it to mount up to 4 panels on either side of the roof, in landscape form, or if it's small remove the roof completely and build your own roof with solar panels, they can overlap on all sides as long as they are properly supported.
Click to expand...
The joys of living in a complex. They appear to be happy with the ZoZo idea, actually they recommended it. To build a structure just for the panels will probably get shot down.

The zozo will also be used for other sorage, so wont be a waste, just trying to get what will work well, at a semi reasonable price.
 
leon.davibe said:
You don't need to buy a high voltage panel to use big inverter

You string panels in series
ie 4 panels with a vmp of 35v would give you a vmp of 140v

So even that may be too much
Inverter dependant

ie some 5kw inverters have a mppt of 145v voc and an mppt range of 60-115

Others have a 100-450v range
Getting 4 panels with a voc of around 50v would put you smack dead in the middle

Keep in mind to use the rule of thumb and don't exceed 80% of the voc
Click to expand...
I will really only be limited to 2 panels, so will get 80v. This is a ground floor apartment.
I have been looking for a 5KW inverter with a 60v MTTP start, do you have a brand/model perhaps?
 
Kroks said:
The joys of living in a complex. They appear to be happy with the ZoZo idea, actually they recommended it. To build a structure just for the panels will probably get shot down.

The zozo will also be used for other sorage, so wont be a waste, just trying to get what will work well, at a semi reasonable price.
Click to expand...
How big will it be?
 
Sinbad said:
Ah.
And why am I a fan of modular systems, not all-in-ones? :D
Click to expand...
That was a option I was looking at.
I checked some of the Victron MTTP units. The one series had a input from 30v, and stated it can handel a 52v battery. Any experience in this perhaps? I am open to all ideas really.
 
Kroks said:
Was hoping for a 2.1x1.8. With the roof pitch I can mount 2 panels total, 2mx 1m.
Click to expand...
Don't they sell them with a flat roof? The pitched roof is such a waste of good space for your application. Try and look for someone who build them and ask for a special order, you can do a lot with a flat, almost 4sqm space.
 
TheChamp said:
Don't they sell them with a flat roof? The pitched roof is such a waste of good space for your application. Try and look for someone who build them and ask for a special order, you can do a lot with a flat, almost 4sqm space.
Click to expand...
I am unfortunately bound by what the body corporate will approve. Looking at something like this, but I don't have the exact spec yet from them.
409ef5e1-1b53-4314-bc18-e56375a36d28-qpn13_large.jpeg
 
Kroks said:
I will really only be limited to 2 panels, so will get 80v. This is a ground floor apartment.
I have been looking for a 5KW inverter with a 60v MTTP start, do you have a brand/model perhaps?
Click to expand...

ledtronix.co.za

5kVA 5kw Pure Sine Wave Inverter MPPT 80A

<p><span style="text-decoration: underline;"><strong><span style="color: #000000; text-decoration: underline;">INPUT</span></strong></span><br /><span style="color: #000000;">Rated Power: 5000VA/5000W</span><br /><span style="color: #000000;">Voltage: 230
ledtronix.co.za ledtronix.co.za

The victron charge controller can handle a 48v battery

Then you can use any inverter you like the price though you can get and inverter/mppt/charger all in one

I would aim for 95v ie 2 x47v voc series string
 
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Kroks said:
I am unfortunately bound by what the body corporate will approve. Looking at something like this, but I don't have the exact spec yet from them.
View attachment 1491743
Click to expand...
The problem is then you actually need 2 charge controllers so the one can face east and catch morning sun and the other afternoon sun , too much costs

If they are fine with the one end of the panel sticking out

Otherwise you are in 2 charge controller valley
 

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The rule of thumb is panels facing same direction on 1 charge controller

Suppose you can try series on one and the output will be suboptimal at all times
ie you won't hit a noon optimum ever and see if it works

So gotta get a flat roof

The fans are only noisy when charge rate or load is high

So most of the time the sound is bearable
 
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Kroks said:
I would live a Sunsync, but it also has the 100v starting range on the MTTP. The Growatt starts at 30v.
Click to expand...
No-one says that you have to use the built-in MPPT. You can hook literally any MPPT controller to the Aux as long as it outputs AC, even microinverters.
 
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