Dillsue

I guess that was from an uninsulated HV cable at 132/400 thousand volts and not really comparable to the OPs domestic supply at 230/400volts. We've got 33000volt cables feeding our transformer and the DNO has recently renewed them giving only a couple of metres clearance for farm machinery to pass under them.

If you want to retain the HW circulating pump you could fit PIR movement sensors in the bathrooms and use those to start the pump as soon as someone walks in but definitely need to insulate the flow and return. You also want to get all that pipework around the cylinder insulated particularly all the tappings other than cold feed. For the tappings you want the thicker walled insulation butted right up to the cylinder casing and ideally shaped so its in contact with the insulation inside the casing. If any or all of your tappings are warm, youre losing heat 24/7!!

Could well be cheaper but may force you to have the shed/ pergola where you don't want it?? Other thing to remember is you're always better mounting panels as high as you can to stop/ minimise shading and lengthen the time the panels are in direct sun.

TBH if the cables are safe to work under I'd just get on and fit your panels. Panels aside, your DNO isn't going to restrict you accessing your roof to maintain it/fit a Velux etc so there's no justification to object to access for panel install. The bottom line is if the DNO is concerned about your proximity to the cables they shouldn't have run them so close over the roof. If the integrity of the insulation isn't certain, let your DNO you're planning to fit panels and ask them to shroud the cables whilst you work. Once they are aware there's panels under their cables they might prioritise shifting the cable??

It is, but best talked about quietly as Great Britain didn't get great by doing environmentally friendly things. I'd hazard a guess that if the UK was tasked with putting right it's wrongs we'd be bankrupt overnight.

Don't be too disappointed as PVGIS predicts 3470 kwh/Yr for us and our actual is 35xx - 37xx/Yr since 2015. The post you were commenting on was quoting a 1.9kwp system which is a modest system and pretty small if you're wanting to go off grid.

I wasn't aware of a time limit on our G99 approval but that's not to say there isn't something buried in the small print! It took our DNO a good 9 months to change a transformer so there's no rush on their side. If your part system is powered up and commissioned then the installer should have already sent the commissioning docs to your DNO so there'll be no clock ticking for you to add the remaining panels. If your roof under the power line is the best place for your panels then probably worth persevering with the inspectors visit on the off chance he gives approval for your extra panels

Assuming the original installer notified/applied to your DNO, then the only red tape/certs you need to bother with are getting a part P spark to check the wiring before you connect it to the inverter. You can install it all and just get your spark to check it if that's what you want. You don't say whether the coiled up cables are connected to the inverter via an isolator? If they are connected directly just be aware that they may be live with several hundred volts on them depending on how things are wired. If there's no isolator you might want to get one fitted before you start working with the coiled cables.

Google EPA section 82. Normal route is via your local authority and section 80, but it can take an age and the LA have to witness the nuisance. As they only work office hours you'll not get far with smoke from a neighbour that lights their fire at 6pm or has a bonfire every Sunday morning. Section 82 is the DIY route.

I believe Greg Jackson is a former software engineer and well into his tech so I guess their systems have been developed to be flexible and easily reconfigured to chop and change products whenever they want

??? Don't really understand where you're coming from

We didn't need to implement limitation so I can't tell what they do practically.... I was just giving you the heads up on cost/risk and potential hassle giving a demonstration for them to witness. Might be annoying to change the inverter but it might be better for you when you factor in the hassle and possible cost to you of continuing with current inverter set to a G98 limit. Only you know if its worthwhile.

It's not comparable as the Solaredge unit is factory limited to 3.68kw so it's G98 compliant out of the box, yet can still handle a large PV input. Your Solis can handle the PV input but needs to be installer throttled to get down to 3.68kw max, hence the G99/G100 I'm not sure if there are other G98 inverters that can take your PV input, but a change of inverter could take you back to a simple G98 notification. One other thing to be aware of is that your DNO reserves the right to witness the export limitation and if its not professionally installed may want to?? Although we ultimately didn't need export limitation our DNO charged £360 to witness the limitation!!

G98 is self limiting to 3.68kw by definition so it's almost certainly a G99 + G100 application that you did/ need to do. It's technically not possible to DIY a G100 compliant system because the limitation setting has to be password protected with a password that only the manufacturer or certified installer knows. The reasoning behind that is if the user has access to the password they can raise the limitation setting whenever they want. Be conscious of this in any discussion you have with your DNO. Don't know what inverter you have but there are G98/3.68kw inverters that will accept your 6.5kw of PV. Latest data I've seen for Solaredge is you can have twice the inverters rating in DC input so a G98 SE3680H can have 7.3kw of PV hooked up to it. No peeing around with G99 or G100, just notify your DNO when the system is up and running.

If you want to get on one of their export tariffs then you'll need an MCS cert/number together with confirmation from your DNO that they approve your export connection, unless you registered your interest and got an invite to join the non MCS trial that they are currently running. That's how things stood last week. If you're installer was MCS accredited when they did your install and you can show you paid them, I'd be fairly sure you'll be able to get an MCs cert from MCS themselves. Might take a bit of coaxing out of them but if the cert is due then you should get it, eventually.

Ah, OK. Not sure if it's always been the case but when I applied to Octopus for export payments last week they didnt need the MCS cert but just the number. I guess they've got access to the MCS database cos they verified the number within seconds.

Talk has turned to action and they're running a trial. Ferdinand was saying he had some issues with documentation which I'm interested to know about as they may pop up for me

Do you know if this is 2 supplies off differing phases with 400 volts between them, or 2 supplies off the same phase with 0 volts between them? With a 4kwp array/battery you'll do well to power 1 ASHP and 1 EVC so a single inverter/battery on one supply would likely use everything the array can provide for most of the time. If you want to charge the battery(s) on a TOU tariff you could have a single battery and a pair of contractors switching the battery between the 2 supplies as required or a battery on each supply. If you've got 2 differing phases coming into the house you may get a 3 phase inverter to run on 2 phases but youd need to speak to the manufacturer to confirm

What was the issue?? We've just applied for Octopus export and it was straight forward- connection confirmation email from our DNO and the MCS cert number. Smart meter went in a few weeks ago so as I understand it Octopus have to request an export MPAN from our DNO and then we're good to go.

Someone posted on here a few weeks ago that they'd been accepted with a non MCS system, but there's a few hoops to jump through based on the requirements they sent me. They're running it as a trial at the moment and are asking for the following- Building control approval for the additional load on the roof Electrical installation certificate from a part P spark. Letter/email from your DNO confirming they accept your export to the grid £250 admin fee You may get an MCS contractor to sign off your installation but they'd likely want a hefty fee to do so and they'd likely have to check through your install to make sure it's as if they had done the work. MCS may not allow it so you'd be asking a stranger for a big favour??

Not sure where he gets his 100% renewables by 2035 from as UK govs BEIS think differently. See section 4- Updated energy and emissions projections 2021 to 2040 - GOV.UK https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1111625/updated-energy-and-emissions-projections-2021-2040.pdf

We fitted a Thermomax system in 2006 and other than a maintenance fluid change its been hassle free. I think they were bought by Kingspan but no idea if they are still in production, nor if spare tubes are available

If you buy an inverter with a 13a socket built into it and plug an appliance directly into it then there's no building control or part P spark needed as its all factory assembled/tested and deemed safe. The moment you start installing 240v cabling/sockets then it comes under BC/part P

I suspect Octopus are asking for what an MCS installer is supposed to do rather than what they actually do. In asking for BC sign off youre unlikely to get away with what MCS installers get away with- our roof was never surveyed for our MCS FIT installation.

Assuming V2G/H gets approved and publicly available in the next year or 2, are you saying Leafs will be a non starter with no compatible bi directional chargers available? I'm guessing there'd be a market to sell Chademo units into??