AC coupled storage system

[Burble61]

With agreement from the FIT provider (easier said than done), the existing inverter could be replaced with a hybrid inverter and if the batteries are capable to be charged from the grid, the generation meter can be changed for a bi-directional one.
https://theecosupermarket.co.uk/product ... ion-meter/

Its in the OFGEM FIT guidance document, page 35, section 4.25.
https://www.ofgem.gov.uk/sites/default/ ... uidnce.pdf


PS - How much PV have you got Westie ?, or average annual generation, for my secret list of Camelot Members Green Generation.
https://camelot-forum.co.uk/phpBB3/view ... f=13&t=922

Thanks Nowty, you knowledge on this stuff is encyclopaedic! I read about bidirectional metering being able to used to allow DC coupled hybrid systems to be allowed under a FiTs contract but never would have found the info you've provided. However even if I achieved legitimately retrofitting a DC coupled hybrid store I can just imagine how many times I'm going to have to explain this to the FiTs provider/meter reader and the actual process of registering the changes to legitimise the system would be challenging - especially as the solar FiTs scheme has ended I suspect. Do know anyone who has succeeded doing this?

Westie, I (did) eventually manage this, although it was a bit of struggle even though I had followed all the rules.

I ended up with Octopus - SSE, my previous FIT provider were very "computer says no", more to do with their systems than anything else I understand.

I did a one page brief for Octopus to explain it - PM me if you would like a copy.

B61

[nowty]

Burble61 and Westie, as you both have admitted to having PV.

Your both not on my secret list yet, the next one is the 50th member and I want to do an update when I get to 50 generating members.
https://camelot-forum.co.uk/phpBB3/view ... f=13&t=922

Basically either tell me how much PV you have got or your average annual PV generation. You can PM me if you want to be the 50th secret person.
We have collectively over a quarter of a Gigawatt hour per year so far.

[Burble61]

haha no escape!

total 3.4 kWp over 2 systems.

Average production over last 3 years 3,059 kWh

Thanks for collating!

[Westie]

I don't see why keeping the existing AC-coupled PV and putting it on the output side of the hybride inverter would be in breach provided it does not involve changing the existing Total Generation metering arrangement. What aspect is it your FIT company does not like?

Thanks Sharpener but you've lost me there! Could you elaborate or sketch it out for me? The aspect they wouldn't like is the ToU grid charging, the TGM on the existing system is unidirectional ie only counts export, so if for instance, the DC coupled battery accumulated 5kwh overnight from the grid the import would not be counted, that would tho add 5kwh to the TGM when the battery was discharged. Nice but illegal

I am suggesting you move the connection between the existing Total Generation Meter and your supply/consumer unit to the output side of a hybrid inverter that has separate input and output connection (e.g. a Victron MultiPlus) like this https://www.victronenergy.com/live/ac_coupling:start.

Then (i) you haven't disturbed the connections between your panels, the solar inverter and the TGM and (ii) there is no possibility of power from the batteries flowing through the TGM in the way you describe, so the DNO should approve your G99 application and you do not need to worry about bi-directional meters or even notify your FIT company.

You can also connect additional PV to the battery via a DC-DC MPPT converter and all this remains true. I can't see why this would not be compatible with a ToU tariff either, I have Economy 7 but others e.g. Agile may suit you better.

Thanks Sharpener, I get it now. That's actually how I was planning to have it connected

It's interesting you say you use E7 rather than Agile. I've been looking at the half hourly rate with Agile and , given the current pricing - pretty much flat at 40p/kWh , I would be better off staying on the Octopus E7 rate 30p peak / 20p off peak.

[Westie]

With agreement from the FIT provider (easier said than done), the existing inverter could be replaced with a hybrid inverter and if the batteries are capable to be charged from the grid, the generation meter can be changed for a bi-directional one.
https://theecosupermarket.co.uk/product ... ion-meter/

Its in the OFGEM FIT guidance document, page 35, section 4.25.
https://www.ofgem.gov.uk/sites/default/ ... uidnce.pdf


PS - How much PV have you got Westie ?, or average annual generation, for my secret list of Camelot Members Green Generation.
https://camelot-forum.co.uk/phpBB3/view ... f=13&t=922

Thanks Nowty, you knowledge on this stuff is encyclopaedic! I read about bidirectional metering being able to used to allow DC coupled hybrid systems to be allowed under a FiTs contract but never would have found the info you've provided. However even if I achieved legitimately retrofitting a DC coupled hybrid store I can just imagine how many times I'm going to have to explain this to the FiTs provider/meter reader and the actual process of registering the changes to legitimise the system would be challenging - especially as the solar FiTs scheme has ended I suspect. Do know anyone who has succeeded doing this?

Westie, I (did) eventually manage this, although it was a bit of struggle even though I had followed all the rules.

I ended up with Octopus - SSE, my previous FIT provider were very "computer says no", more to do with their systems than anything else I understand.

I did a one page brief for Octopus to explain it - PM me if you would like a copy.

B61

Thanks B61, that's good news, pm being sent.

I'm still with SSE-Ovo for FiTs and completely agree with your assesment of their system. I did wonder if moving FiTs Octopus would make it easier and you post has persuaded me.

Which TGM did you opt for or was it specified by Octopus?

[Oldgreybeard]

E7 works for us, not that we have any choice, as we've tried to get a smart meter installed and failed, as the things don't seem able to work here. We're currently paying 17.831p off-peak, 33.26p peak and it works well for us. The 7 hour off-peak period is long enough to stop us using peak rate for most of the year. I would have liked to give Octopus a go but they just aren't competitive for anyone that can't have a smart meter. Pity, as I quite like the idea of investing in Ripple but that seems to be restricted to smart meter users only in effect.

Our FiT is still with SSE but they are a shambles. They have not paid us at all for well over a year now, so owe us over £1,000. I have a complaint lodged via the OFGEM system but I'm not holding my breath when it comes to any swift resolution. I'd gladly switch our FiT to a company that actually answered the phone.

[Westie]

Burble61 and Westie, as you both have admitted to having PV.

Your both not on my secret list yet, the next one is the 50th member and I want to do an update when I get to 50 generating members.
https://camelot-forum.co.uk/phpBB3/view ... f=13&t=922

Basically either tell me how much PV you have got or your average annual PV generation. You can PM me if you want to be the 50th secret person.
We have collectively over a quarter of a Gigawatt hour per year so far.

4.8kWp. Our average over the first 11 years is 4150 kWh a year.

Keep up the good work Nowty

[nowty]

Burble61 and Westie, as you both have admitted to having PV.

Your both not on my secret list yet, the next one is the 50th member and I want to do an update when I get to 50 generating members.
https://camelot-forum.co.uk/phpBB3/view ... f=13&t=922

Basically either tell me how much PV you have got or your average annual PV generation. You can PM me if you want to be the 50th secret person.
We have collectively over a quarter of a Gigawatt hour per year so far.

4.8kWp. Our average over the first 11 years is 4150 kWh a year.

Keep up the good work Nowty

Finally !, your name has been down on my list minus any info for about a month, your now the 59th member.

I'll do an update when we get our 60th.

[Oldgreybeard]

I've just had a look at our inverter. It's showing that we've generated 50,449 kWh since the end of March 2014, so an average of about 6.05MWh per year from a 6kWp system, facing south, in Dorset, with a roof slope of 45°.

We're not on the higher FiT rates, but we're supposed to be getting 18.66p/kWh for the FiT, plus the deemed export tariff (no idea what this is at the moment).