Dillsue

Have a look here https://www.ofgem.gov.uk/sites/default/files/2024-09/Guidance_for_FIT_Generators_V18.pdf section 5.6

Ouch. Through all that sunny weather too!

It is the lower value but definitely worth checking your own figures before jumping from deemed to metered as you can't go back for 12 months. One of our systems is 4kw on 2015 FIT rates and it's only because we have a second self installed system that it was worth giving up the deemed element from the 4kw system and going for metered export from both systems.

That setup needs prior approval via a G99 plus G100 to cover the setup of the export limitation. I think there's an awful lot of inverters that support export limitation but unless the limit is factory set to 3.68kw and G98 documented as such, then you need consent before connecting.

Yes...I missed the presence of 3 phase! If the 3 phase inverter distributes the PV equally over all 3 phases but the house loads aren't evenly balanced across the 3 phases then it may be more beneficial to have a single phase inverter hooked up to the phase with the bulk of the load on it??

Hopefully you're aware that if you want to connect an inverter greater than 3.68kw output you need prior permission from your DNO so a 5kw inverter is a no no without approval

SEG is a government backed scheme that typically pays 4-6p/unit. The 15p/unit rate is a Power Purchase Agreement ie a contract between you and an eleccy company. There's no government involvement/backing and in theory could end at anytime. Lots of people including me sell under a PPA but best that you understand it's different to SEG

Your FIT generation payments won't get affected by switching to a smart tariff. If it's an export tariff then you'll loose your deemed export but still keep the lucrative generation element.

Putin added a bit of fuel to the fire that was already raging with post covid recovery....we were on our 4th eleccy supplier when Russia invaded!!

The SEG is the governments replacement for the FIT scheme but... only pays for actual export and pays a pittance per unit, typically 4-6p/unit. Being on early FIT rates you might be best sticking with your generation and deemed export payments but if you know what you'll likely export in a year you can run the figures. Octopus Outgoing will pay you 15p/unit based on actual export from your smart meter. I don't know what deemed rate you get but you'll probably be better off sticking with what you've got??

Don't you want to export everything you can and charge the battery and hot water overnight on the 7.5p rate....assuming your battery and DHW tank are large enough for a days use??

And watertight insulation if its going underground

I think there's a bit of a difference between a light switch and a thermostat.....one is used frequently through the day and the other is/should be used infrequently. If it's a digital stat then it needs to be at viewing height whereas a switch definitely doesnt want to be that height. If everything was put within easy reach of a wheelchair user/kid then where does that leave the likes of my son in law who's 6'4" and would need to kneel to see a thermostat positioned for a wheel chair user. Its your house so put the stat wherever best for those who are going to use it. Leave a bit of surplus cable in the back box so future owners can lower it easily if they want to.

I think with the Octopus non MCS option you pay £250 to join but get back £100 if they reject you?? How lucrative it is depends on your own circumstances but we'll hopefully be around net £0 over the year for eleccy, so well worth it for us and no batteries needed:)

Without knowing what lies over the boundary, my thoughts would be- Sticking out from your wall 3m up in the air sounds very prominent and may not be to everyone's taste including your neighbour or any future buyer of your house. There's quite a blast of cold air blowing out of most units so think how this might affect your neighbour. Remember that there is statutory nuisance legislation that will trump planning rules. Maintenance access is usually from what would be most installations boundary side ie the side furthest from your house. Typical HP needs 300mm gap from your wall and are min 300mm deep. This would leave 400mm Maintenance access before you needed to work from you neighbours property. Be sure that you can get access for maintenance and repair

When they know in advance then that's probably true. If they're asked to be on standby then it's probably also true. If they need to start unexpectedly then it can take a long time. The turbines have to be gently preheated with steam which I beleive takes hours or maybe days if starting from stone cold. Before you can pre heat you have to get a boiler house up and running to provide the steam for preheating Even if you only want gas generation for an hour or two at tea time each day there's a full team at work round the clock and boiler house running 24/7 keeping the turbines warm for the couple of hours they're needed

He's a lodger not a tenant. He rents an annexe and we're in the main house. When I explained the investment I'd made he was OK paying the full import rate even when he was drawing on our surplus PV......best lodger going:)

I'm sure the overseas investors will sort out a fair price for those north of the border:) I had a similar conversation with our lodger over why he can't have cheap/free electric from the excess PV I've invested £1000s to generate

NESO says sustainable renewables accounted for 37% of UK 2024 generation(wind, solar and hydro) with very expensive nuclear, gas and imports accounting for the bulk of the remainder. Seems to me we've got a long way to go before renewables could drive some savings??

List them on ebay, FB marketplace and anywhere else with no or minimal fees.

Is yours a new build with plumber and spark on site already? With the BUS MCS umbrella schemes you can end up getting all the components, design and commissioning free with you just covering the install costs. Down side is you get what the supplier decides you need and not necessarily what you want/need. I looked at Cleanenergy where everything other than install would have been free but the pump they offered was way oversized and running costs would have been excessive so I'd be paying for their system for ever! I've just started on a self funded/self installed system with a used Therma V pump picked up off ebay:)

Slowly unscrew the pressure gauge. As soon as you can turn it by hand wiggle it and any pressure should vent via the loose threads. Slowly undo it while keeping wiggling, assuming at all times there's 2 bar trapped in the pipework. Keep towel handy!!

If or when the expansion vessels fail the pressure relief valve takes over to stop overpressure so fit one if there isn't one.

If you Google 15mm pressure relief valve you'll see what they look like. If you've not got on the pipework or Sunamp then you probably want to get one fitted to protect the sunamp. Have a look at the manufacturer's instructions for the expansion vessels as they'll tell you what the should be recharged to. The diaphragm inside can fail over time but youll know if they've failed if you cant pre charge them when removed from the install.

I don't think the mains supply gets anywhere near 13 bar so it's unlikely the 13 bar is coming from the mains, if that's where your "cold supply to the sunamp" comes from. If there's a non return valve on the supply then it's possible that as the sunamp charges and warms up the expanding water causes the pressure to increase?? The expansion vessels you mention should absorb this if they are working and connected. There should be pressure on the expansion vessels so probably worth checking that the vessels are connected to the pipework and that they are pre pressurised to allow the internal diaphragm to flex and absorb the expanding water. There should be a pressure relief valve on the vessel/feed to protect the sunamp being over pressured. Is that fitted and working?