Solar for Beginners [ask your questions here]

No worries, I didn't think there was anything wrong with your query! :)

Well, 18 would normally be split into two even strings, so 9x50v = 450v per string.

Another thing to consider is if it's a long cable run, DC (as opposed to AC) will incur a higher loss on the cable. It's hard to give a % loss as it depends on a lot of factors such as temperature, size of the cable, metal used for the wire, but if it's longer than (say) 10m from the solar panels to the inverter, that can play a part. How much is hard to say, but it can be a good reason to avoid a long DC run where possible. I obviously don't know the distances your talking about here, but something to be aware of.

Growatt are common enough. To work out whether they are insular or extroverted in a technology-sense, just have a look at their plugin for HA:

https://www.home-assistant.io/integrations/growatt_server/

Cloud polling = insular. 😆

Me again.

Okay, I got the quote back and it would be an additional €717 to increase from 5 panels to 8. By their estimation, going from 5 to 8 and would generate more kwH than my entire annual usage last year.

Or, I can go from 5 panels to 10, for an additional €1,192, and its estimated will generate about 900 kwH per year more than I used last year.

Advice appreciated!

They're probably paying under €80 per panel + brackets.

I'd echo what everyone will tell you, as many panels as you can realistically afford/fit. It's not JUST about your consumption either. Remember all the suppliers charge a standing rate. Energia charges me €0.74/day, so you have ~€250/year to cover in standing charges too, so exporting as much as you can during summer to cover that too helps!

I use one of these, you can even set up a little script in HA so it switches on when solar is x and house load is y, similar operation to the fancy Eddie ones.

I just charge during the EV window.

30A Hight Power WiFi Wireless Smart Switch, DIY Module for Smart Home Automation, ewelink APP Remote Control, Timer, Compatible with Alexa & Google Home : Amazon.co.uk: DIY & Tools

Thats my thinking also, site visit basically said its much of much splitting them between E/W and very little to gain by using the garage roof…

All plant, now and future will be in that garage on a wall, its a separate building, connected by an arch so will be trunking back to board, ~25m, so splitting a string between roofs is very feasible.

Can you max out the inverter with too many panels because it can only handle a certain kWh, but realistically all panels are not running at 100% efficiency all daylight hours…kinda answering my own Q there.

I have the land, and its all S facing, along a fenceline, but have been advised not to go that route as its a lot more expensive and more open to damage.

Edit to add, he had software that calculated the suns movement and it was much of much how they were splt as far as i remember.