Dillsue

Forget trackers, forget batteries, forget diverters as none of those are needed to get your 4.5kw of panels up and running. You've said the mechanics of mounting them are fine and that's the tricky bit. You can plug and unplug the connectors on a car loom? MC4 connectors are no harder. Fix a 3.68kw inverter to the wall? Get a spark to connect up the mains if you don't want to do that. Fill in your name and address on a G98 and post it to your DNO. What else is stopping you??

Fix panels so they face the sun at some point mid morning to mid afternoon. Plug panels together. Plug the 2 unconnected leads into an inverter using MC4 extension leads if needed. Connect inverter to nearest fuse board through an MCB specified by the inverter manufacturer. Switch the inverter on. Sit back smugly and thank the part P electrician who connected it up for you

Don't forget you need DNO consent if total potential export is over 3.68kw. You can add generation to your FIT system as the rules changed a few years back. If your current system is under performing its likely beneficial to add to the FIT system rather than add a second separate system

Have you thought about how your going to keep a tank full of hot water available during waking hours on a dull day? Paying guests shower in the morning, get p**s wet through during the day then want showers when they get in and a bath for the kids before bed. Be sure to look at DHW and heating from a holidaymakers point of view ie both need to be there when they want them.

?? There's likely auto air vents on the HP circuit and almost certainly if its a pressurised system??

If the tundish is very close to the PRV then yes. If it's a few metres away then personally I'd push it into the PRV vent. If the pipe between PRV and tundish is long and warm you've got the chance of any leaking water evaporating so you'll see nothing in the tundish

If you close all the auto air vent valves so no further air can be expelled that should eliminate them as a source of leakage. Disconnect any vent pipework on your pressure relief valve and push a couple of sheets of toilet paper into the PRV vent so you can see if that's leaking. Repressurise and if you're still losing pressure you've likely got a leak!!

I took it that the pylon TEN times closer had now gone

Have a look at gridwatch to see how little solar we produce even in the summer. We're a million miles off generating more PV than the countries energy demand. Your DNO decides what export capacity you can connect to the grid so don't assume that will "be part of the install". Speak to your installer as they may have already made enquiries on your behalf, or they may be winging it.

Weve got a pylon 300 metres to the back of us and a second one 200 metres to the side. Don't really notice them

A 5 or 8kw inverter will need DNO consent. What does your installer say about that? As JohnMo says you'd be better off charging your EV on the overnight go tariff and let your daytime solar generation run to the grid after you've used what you need. Charge the EV and battery overnight Solaredge doesn't need an internet connection to generate but it does for remote monitoring. I think scheduling of battery charging will need an Internet connection. Why does having a larger EV make you lean towards the larger Givenergy inverter? Our 3.68kw inverter has an integrated 7kw EV charger which charges overnight from the grid so isn't linked to the inverters 3.68kw solar generation capacity

According to our latest bill, our 15p export rate from Octopus is "guaranteed" until next June. How watertight that guarantee is or what happens next June, I don't know!

Lots of the wiring regs are open to interpretation and judgement of the spark/designer of the wiring system so if your expecting/wanting the spark who wires your house to include the DC cabling in his installation cert then probably best to take their advice on how they'd like to see the DC cables installed??

Try and speak to them if you can before you do all the paperwork and pay the application fee. Our DNO was very approachable and we had a verbal agreement within a couple of days. That was formalised with a G99 application. If you've already got one PV system then you should already have submitted a G98 notifcation, or earlier version, for that system. There's not alot of extra work involved between a G98 and G99 application and the single line drawing that you should already have.

Can you get the installers of the system to come round and explain what they've installed and how you should operate it??

Yep, G99 for the second one if it's AC coupled and capable of exporting regardless of where the exported power is coming from. Worth speaking to your DNO before you commit to anything

Don't look at your eleccy usage for the very few days it's very cold as its normal to go through the roof when very cold. For the last 24hrs with it dropping to -2.5 overnight we used 54kwh but this our first winter with a HP so all a leaning curve. WC settings have just been dropped a degree at each end as the wife is too hot:)

If you've already got PV then in most instances any surplus goes to the grid and powers your neighbours. If you then start using the surplus or put it into batteries to power AC then your neighbours are deprived of your surplus so have to increase their draw on the grid. Obviously it's up to the PV owner what they do with the PV they generate, but I don't think that adding AC has no effect on the grid.

If you have 5.68kw of POTENTIAL export then you'll need DNO permission. As rik says a single 3.68kw inverter with dual mppts is the way to go. Each mppt operates independently of the other so will manage the differing output profile from the 2 sets of panels

If youve got AC isn't one of the prime times to run it in the evening and overnight to help with sleeping?

Why 2 inverters? You'll need DNO permission with potentially more than 3.68kw of export. Put the lot on a single inverter. Most/lots of inverters can have way more DC input power than the headline power rating If you enclose the underside then it's no longer a ground mounted PV array but a building clad in solar panels so any planning limits would be those for a garden building rather than a PV array....not sure of Scottish rules though!!

Not sure about that. See https://assets.publishing.service.gov.uk/media/675c0ca798302e574b915336/eep-report-2023-2050.pdf figure 4.1

With a 3kw G98 certified inverter you don't need to ask permission from your DNO, just tell them afterwards, but...... Maybe I'm thinking of someone else but is this Buildings supply piggy backed off another buildings supply?? That might impact DNO permissions. Nothing wrong with secondhand gear but you cant legitimately use an old inverter in a new installation without the inverter complying with current standards.

From the OFGEM guidance for FIT generators, section 5.4- "Generation and export tariffs are also adjusted by the percentage increase or decrease in the Retail Price Index (RPI) over the 12-month period ending on 31 December of the previous year every April, in accordance with FIT legislation." The document is guidance but it does say that the statement is in accordance with FIT legislation?? With the advent of PV diverters and battery storage I could see them varying the deemed export % rate which I beleive the secretary of state can change within the legislation but that likely amounts to peanuts in the grand scale of the countries finances??

Have you got a link to where you've heard that?