Help with first solar PV system shopping list using Victron kit

[Alexx]

6 minutes ago, ProDave said:

In theory yes.  The FIT pays for generation measured on your generation meter, plus a very much smaller rate for "deemed export" which is assumed to be half of what you generate.

 

You can give up the deemed export part of the FIT while still keeping the generation payment, and that then allows you to export on one of the SEG schemes.

 

Contact your FIT provider to discuss it with them.

 

Ah, so I could only export the excess as SEG then, not regular export like with Octopus? I'm trying to clarify with British Gas, they dodge questions all the time, I had to give them screen shots of Ofgem documentation for them to accept what they were meant to accept without questioning. Once I get this sorted, I'll move the FIT to another provider in hope I get better service. 

[ProDave]

Sorry I thought ALL types of export are just called SEG?  Once you have given up the FIT deemed export payment I think you are free do do what you want.

 

 

[Alexx]

5 hours ago, ProDave said:

Sorry I thought ALL types of export are just called SEG?  Once you have given up the FIT deemed export payment I think you are free do do what you want.

 

 

You may be right; I'm still gathering fragments of information and putting it all together so don't take what I'm saying as fact.

 

I'll report back here once I make further progress.

[Dillsue]

9 hours ago, Alexx said:

I have FIT from an existing installation for 2kw that was completely replaced with the Victron kit and panels. They will pay me 25% of my 8kw production, last time I had payment it was like 70p per kwh so that will definitely help with the pay back. I'm still trying to understand if I can get paid for generation and still export at 15p as well. I'm not 100% sure if I can mix and match.

Title is "help with first solar PV system". Bit confusing when you're actually expanding an existing system!

 

The answer to your question about getting paid for FIT generation and separately paid for metered export on a PPA, is yes you can. We do exactly that. Scottish Power pay the FIT generation on our 4kw FIT system and Octopus pay the 15p/unit on the export from the total 12kw we have. You can only change between metered and deemed payments once every 12 months. If your extending your FIT system to 8kw you'll only get FIT payments on the original registered capacity of 2kw so as you say you'll get paid on 25% of what goes through the generation meter

[Dillsue]

3 hours ago, Alexx said:

You may be right; I'm still gathering fragments of information and putting it all together so don't take what I'm saying as fact.

 

I'll report back here once I make further progress.

SEG is the government's successor to FIT and is regulated and must be paid if you apply with a qualifying system.

Outside of SEG, Octopus and maybe others can buy your surplus on a Power Purchase Agreement(PPA) which is an unregulated contract between you and them. Octopus offer both a PPA and SEG but no point in going for SEG when you can get much more on their Fixed or Agile Outgoing tariff 

[Dillsue]

19 hours ago, Alexx said:

 

Inverter can be G100 compliant, here is a document from Victron about it. I have installed pretty much everything already. DNO has been notified, they just keep dragging their feet.

victron-g100-declaration-multi .pdf 1.32 MB · 0 downloads

That's a G100 concept doc. Have you checked the ENA type test register for a compliance cert as a previous post reckoned Victron weren't going through certification??

 

Is it a G99 application you made to your DNO rather than a "notification"?

[pudding]

Have a look on here. Expand the GB specs to see if theres a G100. https://connect-direct.energynetworks.org/device-databases/search-gen?manufacturer_id=66

[Alexx]

20 hours ago, Dillsue said:

Title is "help with first solar PV system". Bit confusing when you're actually expanding an existing system!

 

The answer to your question about getting paid for FIT generation and separately paid for metered export on a PPA, is yes you can. We do exactly that. Scottish Power pay the FIT generation on our 4kw FIT system and Octopus pay the 15p/unit on the export from the total 12kw we have. You can only change between metered and deemed payments once every 12 months. If your extending your FIT system to 8kw you'll only get FIT payments on the original registered capacity of 2kw so as you say you'll get paid on 25% of what goes through the generation meter

I moved into a house that had already a solar PV system in place, but it was old, not performing well, at best it generated 500w of the 2000. I didn't install or touched it, as soon I moved in I started converting the loft so the whole roof went, and with it all the existing solar PV array.

 

Great to know, so the system will pay itself back much quicker this way.

[Alexx]

4 hours ago, Dillsue said:

That's a G100 concept doc. Have you checked the ENA type test register for a compliance cert as a previous post reckoned Victron weren't going through certification??

 

Is it a G99 application you made to your DNO rather than a "notification"?

 

Great news, I've just got approval today from DNO and we have the 8kw approved. We used the document I mentioned earlier. Yay!

[Alexx]

4 hours ago, Dillsue said:

That's a G100 concept doc. Have you checked the ENA type test register for a compliance cert as a previous post reckoned Victron weren't going through certification??

 

Is it a G99 application you made to your DNO rather than a "notification"?

it was an application

[Dillsue]

10 hours ago, Alexx said:

I moved into a house that had already a solar PV system in place, but it was old, not performing well, at best it generated 500w of the 2000. I didn't install or touched it, as soon I moved in I started converting the loft so the whole roof went, and with it all the existing solar PV array.

 

Great to know, so the system will pay itself back much quicker this way.

Great that you got your 8kw export.

 

If you've not already done it have a read of the FIT rules re system extensions so you get all the total and net installed capacities correct

[Alexx]

I just realised I have another problem now.

 

My energy meter was between the old inverter and my consumer unit, that was a system with no batteries.

New inverter is in a garage about 20m away from the house on a sub consumer unit.

 

My generation will only be realised when the house uses it, not when it is actually generated because I will store on the batteries a good portion of it, which will be accounted as generation once the house demands it or I export. This would not allow me to have a night tariff to charge my batteries as the FIT is only valid for energy generated from solar PV.

 

I was thinking maybe I get a bi directional meter to subtract what I import overnight from what I export during other hours, but it seems I cannot do that due to FIT requiring all generation to come from solar (even if stored on batteries) as long it does not come from the grid.

 

Not sure what to do

[Dillsue]

7 hours ago, Alexx said:

I was thinking maybe I get a bi directional meter to subtract what I import overnight from what I export during other hours, but it seems I cannot do that due to FIT requiring all generation to come from solar (even if stored on batteries) as long it does not come from the grid.

 

Not sure what to do

Read the FIT rules!! Your config is likely allowable with a new bidirectional meter doing net metering. Anything drawn from the grid and put into batteries is deducted from energy flow to the house/grid giving a net reading of what was generated from solar. It's all covered in the FIT generator rules and/or guidance docs from Ofgem. Don't expect or trust that BG staff will understand the finer details so you could well have a bit of an uphill struggle but you'll get paid in the end if you know and stick to the rules.

 

There's also a guidance doc for FIT payers(BG) detailing how they should manage you so that's worth a read of the sections covering what you want to do.

 

Have fun!

[Alexx]

21 minutes ago, Dillsue said:

Read the FIT rules!! Your config is likely allowable with a new bidirectional meter doing net metering. Anything drawn from the grid and put into batteries is deducted from energy flow to the house/grid giving a net reading of what was generated from solar. It's all covered in the FIT generator rules and/or guidance docs from Ofgem. Don't expect or trust that BG staff will understand the finer details so you could well have a bit of an uphill struggle but you'll get paid in the end if you know and stick to the rules.

 

There's also a guidance doc for FIT payers(BG) detailing how they should manage you so that's worth a read of the sections covering what you want to do.

 

Have fun!

ow, I missed that bit, thanks for pointing out!

[Dillsue]

The FIT rules changed in December 21 to allow alterations and batteries so make sure you find the version dated then or later

[Alexx]

3 hours ago, Dillsue said:

There's also a guidance doc for FIT payers(BG) detailing how they should manage you so that's worth a read of the sections covering what you want to do.

Do you have a link/URL for that by any chance? I'm not sure if I'm checking the correct document. Thanks!

[Dillsue]

10 hours ago, Alexx said:

Do you have a link/URL for that by any chance? I'm not sure if I'm checking the correct document. Thanks!

Google "Ofgem fit guidance" and youll find- https://www.ofgem.gov.uk/publications/feed-tariffs-guidance-licensed-electricity-suppliers

And- https://www.ofgem.gov.uk/publications/feed-tariffs-guidance-fit-generators

[Originaltwist]

Anyone following all this should take careful note of the suggestion of micro inverters from @SteamyTea

They are best for multiple orientations

The setup is simple

But, most importantly, they last for about 20 years whereas a whole bunch of various boxes, all with a 10 year life expectancy, is asking for a series of catastrophic failures down the line.

[Dillsue]

21 hours ago, Originaltwist said:

Anyone following all this should take careful note of the suggestion of micro inverters from @SteamyTea

They are best for multiple orientations

The setup is simple

But, most importantly, they last for about 20 years whereas a whole bunch of various boxes, all with a 10 year life expectancy, is asking for a series of catastrophic failures down the line.

I think that to do what the OP is doing you'd need a few extra bits and bobs off the roof to get the same functionality with micro inverters.

 

The thing to be conscious of with anything active up on the roof is replacement if they go wrong. I don't know what the failure rate is of micro inverters but we're waiting delivery of the 3rd failed optimiser from one of our systems. They come with a 25yr guarantee but that's not an indication of how long they'll last, just means we get the part free. Fortunately I have the kit to replace them so it's just my time to put up a scaffold tower but if you have to pay someone to change them it can be £100s

[Alexx]

22 hours ago, Originaltwist said:

Anyone following all this should take careful note of the suggestion of micro inverters from @SteamyTea

They are best for multiple orientations

The setup is simple

But, most importantly, they last for about 20 years whereas a whole bunch of various boxes, all with a 10 year life expectancy, is asking for a series of catastrophic failures down the line.

definitely not, if a micro inverter goes bad, I need scaffolding and a lot of hassle to replace it. if my inverter fails, I can just replace it without having to touch the roof. To my point of view it makes no sense to touch micro inverters, they offer no benefit over a regular inverter. I would need AC coupled batteries to start with which is a completely no go for me. DC couple batteries like Gobel, Seplo, Fogstar and others are many times cheaper. Your point about multiple orientations would be the only benefit if I could not replicate the same with another system. 

Edited Monday at 07:33 by Alexx

[SteamyTea]

8 hours ago, Alexx said:

definitely not, if a micro inverter goes bad, I need scaffolding and a lot of hassle to replace it. if my inverter fails, I can just replace it without having to touch the roof

But.

If a panel, or a wire even, goes bad, then you need to check all the installation.

 

(Not really a fan of micro inverters, but they have their place)

[Nickfromwales]

Just fit optimisers if you want to be able to narrow down finding a duff panel. Or fit panels that simply live, nearly, forever. 
 

🇩🇪 

[Alexx]

15 hours ago, SteamyTea said:

But.

If a panel, or a wire even, goes bad, then you need to check all the installation.

 

(Not really a fan of micro inverters, but they have their place)

from my understanding that can happen, but the likelihood is much smaller than an inverter or microinverter failing. multiplying the single inverter by 20 times will definitely increase the chances of getting a bad microinverter for sure, that is just statistic, If that is 0.01% rate, now you multiply that by 20, then now you start having 0.2% failure rate. 

 

I understand micro inverters have their place, like multiple different orientations, and if you have an AC coupled battery, besides that I struggle to see the benefits. In my case I ended up going all the way with additional MPPTs on the Victron system. I'm even considering in the near future making a solar fence, so I can just buy another £150 to £300 MPPT depending on the size and put several panels on it. That is the modularity I was after, but I'm definitely having to pay a fair bit more money for the privilege 

[Alexx]

12 hours ago, Nickfromwales said:

Just fit optimisers if you want to be able to narrow down finding a duff panel. Or fit panels that simply live, nearly, forever. 
 

🇩🇪

all victron documentation strongly discourage using optimisers as they would conflict with the MPPT own way of dealing with the panels. Also panels have 3 diodes from what I can see. As soon I have some data from the system I'll put my findings to confirm how this works in practice. 

[Nickfromwales]

23 minutes ago, Alexx said:

all victron documentation strongly discourage using optimisers as they would conflict with the MPPT own way of dealing with the panels. Also panels have 3 diodes from what I can see. As soon I have some data from the system I'll put my findings to confirm how this works in practice. 

I've not got any direct experience with Victron, but unless you have optimisers you cannot find a dead panel without checking each one. We've installed systems with optimisers (Tigo) for yonks without any issues whatsoever, quite the opposite tbh.