sanch3z

ok, that's my lack of knowledge shinning through again... get used to it 😉

sorry to hijack. I'm starting out and looking at victron as they review well, and have been around a while. I can see advantages and disadvantages of one box does all: Advantages - Compatability - Less companies to deal with - Easier to fault find Dissadvantages - Can be more expensive than seperates - If one thing breaks the whole thing breaks - No ability to swap out failed element or upgrade Now the warranty of 5 years is ok, but if it only lasts that long than that's £650+ a year. Does this represent good value? I know nothing about PV equipment and manufacturers so might need a reality check. Happy to have one

if your panels draw the 5.7kw and are connected to a G98 rated 3.68kw inverter, what's happens to the surplus 1.2kw? is it used, or effectively ignored? I understand that a 6kw array is unlikely to pull the full 100%, more like 4.8-5kw so it makes sense to have more panels to account for the loss

they have a special setting reserved for use with their own gear. You can disable this if you want to use it with other inverters by all accounts

yes, yes he does. but get the point...

no but i'm not sure scaffolding is necessary. I'll likley get my mate up there... owes me a few favours and is better with heights.

well, this is part of a proposed extension that includes a loft extension. Which is the reason i'm looking at DIY as i'll have the trades and scaffolding up. There is the possibility of creating a small cupboard/access panel to house something like this. I didn't know if anyone has done this sort of thing before. Basically increase the length of the optimiser cables and move them inside. That way unless a panel breaks, everything is reachable... Saying all this, what's wrong with an old fashioned ladder? A mate does bird proofing of PV systems and it's done via ladders. Just need to turn everything off, nip up, swap an optimiser and away you go?

Had a quick read of tigo optimisers, they sound flexible but they have a single point of failure. They act as a tunnel for current to flow, so if one goes they all go. Back to needing scaffolding etc. to fix the issue. Why don't people make these things more accessible???

yes, it would seem like you are doing a 5.6kw system a disservice throttling it to a 3.6kw inv. It's probably worth paying the money, and going G99. I have read that some energy companies refuse to let you connect to them unless you get an MCS install ticket, and lots of these ppl/compaines will only certify a system they provide. Over a Barrell here!!!

ok, you've touched on a very important point for me – serviceability. I'm keen to include either optimisers, or inverters on each panel to cover the shady issue, but my problem with this is servicing when one eventually has an issue. Is there a way to add these somewhere, that's more accessible, or are they always going to be situated on the rear of the panel? If they are then how do you limit exposure to issues?

Interesting strategy looking at used automotive batteries, it sounds shrewd but i'm not sure i'm brave, or knowledgeable enough to go down that route! With regards to the size of my PV array. I feel it makes sense to max what my roof will take. Whilst the scaffolding etc. up I might as well add what I can. I still want a 8-10kw battery for the nights and winter days though, and I would rather do stuff in one hit so I can make sure it's working well together before any trades leave. Very interesting point about SolarEdge... I know very little about them, expect their batteries in the EU currently don't offer islanding however they are hoping to add this certification early next year.

extra compatible controllers like eddi will need adding to the system to maximise it's potential. Personally speaking i'm leaning towards the Hyundai panels as they have a better spec and higher capacity for the relative space. But the eco-worthy solution made my question whether the other system my pal is getting for £17k is good value. He's no dummy so has done his own reading and research but when I see two systems at apparent ends of the scale i'm forced to ask "is there a suitable solution in the middle, can I get a 5.6kw system with a 10kw battery around the £12k mark?"

shame there's nobody out there stripping and testing these batts, seeing if the thermal cut-off etc. is there and works correctly...

Interesting. I think the reason that kit is pitched at 'off-grid' (not that I want that), is because it's mostly aimed at people with Caravans, or small workshops. LiFePO4 is certainly an interesting topic, and one that needs more discussion as the cost of most systems are doubled when batteries are added. With regards to their cons, it would see not operating in cold conditions is the only one. I've seen posts on YouTube that recommend seating the inverter below the battery stack as the heat is passed up through keeps them warm. Personally speaking my entire set-up if possible, will go in my garage that's part of the house, so it never experiences super low temps.

isn't it based on the size of the inverter rather than the PV capacity? So as long as the inv falls below the tolerance (3.6kw (I think)) a G98 is sufficient. This does raise another question though... If your PV array is 5.6kw, why throttle it to a 3.6kw inv, as surely the most you will be able pull/use is 3.6kw? I know PV will never all run at maximum capacity, but that's only using around 65% of the PV capacity. Is the theory you're covering yourself for more cloudy days? If you're running a decent sized battery it seems silly to waste stuff on these days???