Solar PV documentation 27 October 2022 at 12:04PM in Green & ethical MoneySaving 15 replies 464 views

Bianchiintenso

A bit of advice please having read some posts about not receiving documentation at end of installation in a timely manner.
I am having an 8Kw system and 10.24Kw battery installed mid November. Have installed a smart meter in the hope of exporting any surplus.
What documentation should I make sure I have before I pay the final payment?
TIA

QrizB

What I got (eventually, after lots of hassle ...)

1. "Paid in Full" invoice
2. MCS Certificate
3. G98 form
4. G98 acknowledgement from DNO
5. Building Regs compliance certificate
   
6. Manufacturer's warranty docs for panels and inverter
7. Manufacturer's data sheets for panels and inverter
8. Installer's warranty
9. Insurance-backed guarantee certificate and T&C#
10. System schematic
11. SAP PV performance estimate

The first five are must-haves. The next four you can get by without provided you never need to make a warranty claim. The last two are nice to have but not essential.

Raxiel

I have the DNO acknowledgement letter (4) but not the form itself (3). I presume that's not just a copy of the form submitted, but a copy returned from the DNO with their stamp on it?

If it's the latter, I have heard from multiple sources that the DNO's have a bit of a backlog, with a G98 taking up to 3 months at the moment.

Octopus only asked for the letter during my application for an export tariff, so I hope it doesn't delay things, but I suppose winter is the least worst time to be missing out if it's the case.

QrizB

My G98 letter is just a copy of the one the installer submitted.

If you've got the DNO's acknowledgement, you may never need a copy of the original. (Perhaps I was a bit over-zealous describing that one as "essential"!)

Bianchiintenso

QrizB said:

What I got (eventually, after lots of hassle ...)

1. "Paid in Full" invoice
2. MCS Certificate
3. G98 form
4. G98 acknowledgement from DNO
5. Building Regs compliance certificate
   
6. Manufacturer's warranty docs for panels and inverter
7. Manufacturer's data sheets for panels and inverter
8. Installer's warranty
9. Insurance-backed guarantee certificate and T&C#
10. System schematic
11. SAP PV performance estimate

The first five are must-haves. The next four you can get by without provided you never need to make a warranty claim. The last two are nice to have but not essential.

Excellent thanks, installer applied for DNO, it said on quote 4kwh DNO fee, although it’s an 8kwh system, does that simply mean the G98 applies to ‘over 4kwh’? If that makes sense?

Raxiel

G98 is a simple notification (Installers may charge an admin fee to do it, but the DNO doesn't charge to process it)  that is submitted after install and is automatically granted outside exceptional circumstances. Under a G98 export is limited to 16A or 3.68kW.

You can have more generation capacity, but anything beyond 3.68 will be lost if you can't use or store it (so unlikely to be an issue with your battery).

To be able to export more you need a G99 or G100 which have a fee and must be approved in advance.

Bianchiintenso

ahh must be a G99, that would explain the £450 fee, given it's an 8kW system and Inverter

ABrass

You should have G99 or G99 and a G100. G98 would not be valid for you.

G98 applied to systems that cannot breach the 16A mark, aka 3.68kW or 4kW.

If you could generate more than 16A then you would have a G99 if you wish to export all that power. If you have some form of export limiter then you would need a G99 and a G100.

With G99 you get an initial agreement from the DNO, which you will probably never see as your installer will do that, then once complete you should receive a copy of the approved form.

DNO turnaround varies based on region.

Bianchiintenso

Apparently they wouldn't goahead until they had DNO approval, which they recieved last week, so 3 weeks and counting till install

ABrass

Bianchiintenso said:

Apparently they wouldn't goahead until they had DNO approval, which they recieved last week, so 3 weeks and counting till install

That's not unusual, if the DNO turned around and said you could only have 3.68kW export then you might decide you want a different system or might not go ahead.

Now you have the first stage of approval your installers can install your system, then let the DNO know who will think about things for a few weeks before sending back the approval form that you need to get SEG.

Bianchiintenso

ABrass said:

That's not unusual, if the DNO turned around and said you could only have 3.68kW export then you might decide you want a different system or might not go ahead.

Now you have the first stage of approval your installers can install your system, then let the DNO know who will think about things for a few weeks before sending back the approval form that you need to get SEG.

Thanks for that, I was naively thinking getting DNO approval meant I could export any surplus, not that there was another stage to go, learning lots🙂