Adding South String at €450 per panel?

...Ghost...

Does this seem a bit mental?

I got a quote for 3.5kW system with 8 jinko 435 panels and a solis hybrid inverter for €8k before grant which falls roughly in line with quotes I was getting last summer.

The sales guy then suggested I consider adding 8 panels to the north roof which would be roughly 60% (realistically 50% due to chimney shade) of the south panels and only add 6 months (or 1 year) to the payback period. The thing is the price is then €11.5k before grant. If adding north panels, optimisers would then be needed for all 16 panels (quote included 16 optimisers if getting north panels). That's roughly €450 per north facing extra panel where I would have expected to pay less than €300 per panel max.

Am I mad to even consider it? We are heavy users and would consume everything generated if that helps.

Note: If I stick to only South panels, I would plan to install a second string when I complete my shed extension this year. The tilt of the shed is about 10 degrees north facing and I would fit 6 panels on it in landscape orientation. Between panels, rails, wiring and other bits, I wouldn't expect to be paying more than €1k for greater performance than 8 panels on the north roof of the house.

Any thoughts on this welcome.

AmpMan

forgot the north facing panels . waste of money

I wouldn't put individual microinverters on a roof as invariably one will fail and you will need to access it which could be painful. Could you install a string on the south roof and another string on the north, you could then add panels to your shed later on microinverters.

idc

If you have only 8 panels for South Roof that is one MPPT on your inverter. Surely north facing panels could just be added to the second MPPT. Unless you've already told the sales guy you want to use the second string for your shed

The way you mention if adding the 8 north required 16 microinverters sound like you actually mean optimisers but again you don't need them if your going to use two separate strings on your Inverter.

...Ghost...

https://www.boards.ie/discussion/comment/121698925#Comment_121698925

The optimisers would definitely be needed if I put panels on the north roof because of the chimney. I share the concern of adding several points of failure on a difficult to access roof. I think it may be best to just leave out the north roof and go with plan B on the shed later in the year.

https://www.boards.ie/discussion/comment/121698958#Comment_121698958

I meant optimisers yes. Edited OP.

I think the sales guy was quoting to optimise all panels into a single string. I would only need to optimise maybe 4 north facing panels due to a chimney, but as I said above, I am concerned about failure points and accessibility.

just going with south might make most sense for now on a single string.

Paul Kiernan

https://www.boards.ie/discussion/comment/121699251#Comment_121699251

I thought you'd only need optimisers on the panels shaded by the chimney, not all of them?

DC999

Only add North panels when all other S, E, W spaces are filled. Then DIY N yourself on your shed as you say. 

...Ghost...

https://www.boards.ie/discussion/comment/121699740#Comment_121699740

I was thinking 16 were quoted if North and south were crammed into 1 string.

https://www.boards.ie/discussion/comment/121699866#Comment_121699866

I only have north and south as options. The shed panels would be instead of the north roof panels.