3 panels east 3 south, Tigo Optimisers and their reliability.

[Mr Gus]

Sorry to off-topic again, Nowty, do you consider a covered dog run & a basic covered pergola exempt & therefore acceptable by definition to circumvent as per potting shed? (Covered being solar & neither of course watertight)

We aren't allowed sheds here (though some have them) therefore if someone were to be @rsey, the combination of shed + solar would likely get council attention, we need a separate "stealth solar" thread for this ..hidden from the authorities, ...any council planners in our midst?

[Oldgreybeard]

The canopy I'm part way through building gets around the PV restrictions by being within Permitted Development as a covered walkway. The fact that the roofing happens to be solar panels doesn't change that, AFAIK. I have opted for all-black panels so they don't look too obvious, but it would be hard to see how the planners could object.

[nowty]

Sorry to off-topic again, Nowty, do you consider a covered dog run & a basic covered pergola exempt & therefore acceptable by definition to circumvent as per potting shed? (Covered being solar & neither of course watertight)

We aren't allowed sheds here (though some have them) therefore if someone were to be @rsey, the combination of shed + solar would likely get council attention, we need a separate "stealth solar" thread for this ..hidden from the authorities, ...any council planners in our midst?

I'm in a 70's suburban estate so generally you can get away with most things.

I have a stealth panel (on a TIGO) on my car port facade.
The facade was white, so I painted it black and added a fake wood extension piece on top which I also painted black.

[AE-NMidlands]

That's a bloody big panel!

[Mr Gus]

The canopy I'm part way through building gets around the PV restrictions by being within Permitted Development as a covered walkway. The fact that the roofing happens to be solar panels doesn't change that, AFAIK. I have opted for all-black panels so they don't look too obvious, but it would be hard to see how the planners could object.

& Its pretty easy to spray silver frame edges too, thankfully.

[Stinsy]

Thanks for all the replies guys.

If I were you I’d do 6x south-facing panels on one string. And have the other string with 6x south and 3x east facing with Tigos on all 9.

What are the advantages of doing this instead of:
3x south facing and 3x east facing with Tigos on all 6 and the other string with 9x south?
I don't mind paying the extra £150 for three more Tigos if I can see a benefit.

It is about voltage!

If it is afternoon and the 3 East-facing panels are shaded then their Tigos will drop the string voltage to a level that might make the string voltage outside the MPPT range and therefore the South facing will do nothing even though they’re in full sun.

[nowty]

Without specifics on your kit we can only give you generalisations, Stinsy is being correctly cautious.
We don't know your MPPT's operating range and we don't know your panel spec, if your inverter will operate ok with large power imbalances between each MPPT input, etc.

As Stinsy previously said, "It’d be much easier to help if you posted the specs of the panels and inverter."

Just the model numbers will do.

[ChrisJEvans]

Thanks for all the replies guys.

If I were you I’d do 6x south-facing panels on one string. And have the other string with 6x south and 3x east facing with Tigos on all 9.

What are the advantages of doing this instead of:
3x south facing and 3x east facing with Tigos on all 6 and the other string with 9x south?
I don't mind paying the extra £150 for three more Tigos if I can see a benefit.

It is about voltage!

If it is afternoon and the 3 East-facing panels are shaded then their Tigos will drop the string voltage to a level that might make the string voltage outside the MPPT range and therefore the South facing will do nothing even though they’re in full sun.

Sorry I missed the request for Specs.

Collecting today from Wagner Renewables (Sussex)
15 x JA SOLAR 385W Mono Half Cell Black Frame W/B (JAM60S20MR BF)

I've ordered a
Solis 6.0 ES Hybrid Inverter (with DC)

but Wagners have said they should be able to get sooner
Solis RHI-(3-6)K-48ES-5G
or
GoodWe GW3648-EM GW5048-EM Battery Input Data Battery Type Li-Ion

But they seem lower power so I'm reluctant, suggestions for alternatives that will be available this year please?

p.s. Looking to the future I think I could fit another 5 or 6 panels to my main East facing roof but as that is easy to access from the flat roof as there is a ground floor extension and I won't need full scaffolding, I'm leaving that in reserve!

Summary of arrangement
Two south facing pitched roofs each with 3 panels
One East facing pitched roof with 3 panels
Flat roof with 6 panels they can all face south. Three rows of two panels. From about 2p.m. the panel in the north west of the block will start to be shaded. I could as shown in the second image below have 3 facing east and three south.

[Stinsy]

Lower power inverter is fine. 3.6kW is perfect for most people. Your panels won’t generate their rated power very often or for very long because in summer they’ll get too hot, and at other times of the year the sun won’t be intense enough or at the right angle.

Under NOCT conditions your panels are 32.96Vmp, making 3 of them 98.88V. If your inverter MPPT works down to 90V then you’ll be fine, but if it only works down to 120V (or anything else higher than 100V) it is likely not to work very well.

[nowty]

Lower power inverter is fine. 3.6kW is perfect for most people. Your panels won’t generate their rated power very often or for very long because in summer they’ll get too hot, and at other times of the year the sun won’t be intense enough or at the right angle.

Under NOCT conditions your panels are 32.96Vmp, making 3 of them 98.88V. If your inverter MPPT works down to 90V then you’ll be fine, but if it only works down to 120V (or anything else higher than 100V) it is likely not to work very well.

I agree with Stinsy.

And the second longer string should be OK as you need 13+ panels in a string to exceed the max voltage, say 12 to be safe, so 9 on the other single string is also fine.