Inverter confusion

[SteamyTea]

17 minutes ago, pocster said:

it cannot know if SWMBO will reenact a bake off episode

It will know if Nigella is on your telly and you are watching Whack Off.

[Pocster]

Spoke to DNO because I don't like giving up. No chance of 2nd Powerwall . So looking at extra SE battery and the question of can PV input be split amongst them.

[Dillsue]

You've already got consent for 8.7kw export so configure your SE inverter to zero export, existing Powerwall to 5kw and new Powerwall to 3.68kw. Max export will be what it is now and youll have 5+3.68+3.68kw to use in the house. You'll likely need to do a G99+G100 application.

 

I think youve already got a SE energy meter so SE configuration will just need the export limit setting, but check your inverter has a G100 certificate

 

Simples

[Pocster]

5 minutes ago, Dillsue said:

You've already got consent for 8.7kw export so configure your SE inverter to zero export, existing Powerwall to 5kw and new Powerwall to 3.68kw. Max export will be what it is now and youll have 5+3.68+3.68kw to use in the house. You'll likely need to do a G99+G100 application.

 

I think youve already got a SE energy meter so SE configuration will just need the export limit setting, but check your inverter has a G100 certificate

 

Simples

Not simples !

DNO won’t allow 2nd AC device due to effecting neighbors voltages .

I wish Tesla would bring out a power wall battery extender . Just plugs into existing PW and use just that inverter - not 2 .

[Pocster]

Mulling another se battery if I can mitigate the dreaded vat ….

[Pocster]

What’s to stop me installing a 2nd battery myself ? 

[TonyT]

Go full DC route so no DNO involvement 

[Pocster]

12 minutes ago, TonyT said:

Go full DC route so no DNO involvement 

Yeah I’m thinking this way . SE install of an additional dc SE battery looks like a simple plug n play option . What could possibly go wrong ?

[Johnnyt]

47 minutes ago, pocster said:

Yeah I’m thinking this way . SE install of an additional dc SE battery looks like a simple plug n play option . What could possibly go wrong ?

 

Let me know the best price you can get a second energybank for.

I've been quoted £6.5k net with no vat as existing system with one energybank yet to be signed off on new build.

Edited May 10, 2023 by Johnnyt

[Pocster]

3 minutes ago, Johnnyt said:

 

Let me know the best price you can get a second energybank for.

I've been quoted £6.5k net with no vat as existing system with one energybank yet to be signed off on new build.

I found this for similar price ( inc vat ) 

 

https://www.solartradesales.co.uk/solaredge-home-battery-10kwh-battery-v02-400v

 

Edited May 10, 2023 by pocster

[Pocster]

Just now, pocster said:

I found this for similar price ( inc vat ) 

 

https://www.solartradesales.co.uk/solaredge-home-battery-10kwh-battery-v02-400v

 

Wonder if I can do a deal with a sparky to do the install and a deal on the price if he purchases and claims the vat back 🤔

[Dillsue]

4 hours ago, pocster said:

Not simples !

DNO won’t allow 2nd AC device due to effecting neighbors voltages .

I wish Tesla would bring out a power wall battery extender . Just plugs into existing PW and use just that inverter - not 2 .

There's no difference between a 3.68kw Powerwall exporting and a 3.68kw SE inverter exporting. If you disable the SE inverters export and replace it with a second Powerwall theres no difference to the grid as its still 8.7kw total. When you asked your DNO about adding a second Powerwall(3.68kw)did you tell them you are disabling the SE inverters export??

 

If it's more storage youre after then go for the extra SE battery. If you want more power to the house then adding an SE battery wont make any difference as your SE is limited to 3.68kw

[Pocster]

14 minutes ago, Dillsue said:

There's no difference between a 3.68kw Powerwall exporting and a 3.68kw SE inverter exporting. If you disable the SE inverters export and replace it with a second Powerwall theres no difference to the grid as its still 8.7kw total. When you asked your DNO about adding a second Powerwall(3.68kw)did you tell them you are disabling the SE inverters export??

 

If it's more storage youre after then go for the extra SE battery. If you want more power to the house then adding an SE battery wont make any difference as your SE is limited to 3.68kw

The DNO understands . Export is not the issue . 2 ac powerwalls on 1 phase cause the issue . It’s because they are AC devices .

[dpmiller]

it's the amount of export that makes the voltage rise, regardless of how many inverters you have. Inverters work by pushing power into the house and grid.

More production, less load in the house, and poor DNO infrastructure all have the same effect- to make local grid voltage rise.

[Pocster]

1 hour ago, dpmiller said:

it's the amount of export that makes the voltage rise, regardless of how many inverters you have. Inverters work by pushing power into the house and grid.

More production, less load in the house, and poor DNO infrastructure all have the same effect- to make local grid voltage rise.

A 2nd PowerWall even with an export limiter will cause voltage variation especially on single phase . Of course it depends on the infrastructure and where you are on it . I spoke to DNO again just a few days ago - they won’t allow it . Because potentially the voltage variations could affect my neighbors. Also I asked what if all my immediate neighbors asked for pv . Then apparently they would all be capped at 1.89kw export .

[Dillsue]

5 minutes ago, pocster said:

I spoke to DNO again just a few days ago - they won’t allow it . Because potentially the voltage variations could affect my neighbors.

Did you tell them that you would set the SE to zero export to keep total export under the limit you already have?

 

I understand that Tesla specs include multiple Powerwalls for the UK market so there's some disparity between what your DNO seems to be saying and what Tesla are saying. 

[Pocster]

Just now, Dillsue said:

Did you tell them that you would set the SE to zero export to keep total export under the limit you already have?

 

I understand that Tesla specs include multiple Powerwalls for the UK market so there's some disparity between what your DNO seems to be saying and what Tesla are saying. 

Yes . Told them I’d even be happy to have the export limitation increased !!

[Dillsue]

7 minutes ago, pocster said:

Yes . Told them I’d even be happy to have the export limitation increased !!

Maybe let Tesla know then as your DNO citing 2 Powerwalls as a problem might be of interest/concern to them

[Pocster]

Just now, Dillsue said:

Maybe let Tesla know then as your DNO citing 2 Powerwalls as a problem might be of interest/concern to them

Spoke to Tesla . They aren’t interested 

[Dillsue]

2 minutes ago, pocster said:

Spoke to Tesla . They aren’t interested 

My guess would be because 2 powerwalls isnt really a problem??

[Pocster]

9 minutes ago, Dillsue said:

My guess would be because 2 powerwalls isnt really a problem??

2 powerwalls isn’t an issue . It can be possible on single phase . DNO has the issue . I can’t win at argument against the DNO - I’ve tried trust me .

[Dillsue]

9 minutes ago, pocster said:

2 powerwalls isn’t an issue . It can be possible on single phase . DNO has the issue . I can’t win at argument against the DNO - I’ve tried trust me .

If you really want a second Powerwall maybe ask your installer and Tesla if theres a reason they can see for the DNOs objection and if not, make a complaint firstly to the DNO then to OFGEM.

 

DNOs arent always correct in what they say!  When we applied to add a second 3.68kw system to the 3.68kw system we already had, the lad that was doing the intial assessment said we would need to have export limitation on the new system. It took a few emails before the penny dropped that the second system was inherently limited to 3.68kw.  We got approval despite initial objection/confusion.

[Pocster]

2 minutes ago, Dillsue said:

If you really want a second Powerwall maybe ask your installer and Tesla if theres a reason they can see for the DNOs objection and if not, make a complaint firstly to the DNO then to OFGEM.

 

DNOs arent always correct in what they say!  When we applied to add a second 3.68kw system to the 3.68kw system we already had, the lad that was doing the intial assessment said we would need to have export limitation on the new system. It took a few emails before the penny dropped that the second system was inherently limited to 3.68kw.  We got approval despite initial objection/confusion.

Yeah I’ve tried getting the installer to go with me . I did consider a complaint - though of course DNO might win . A dc battery zero hassle and cheaper I guess .

[Carrerahill]

28 minutes ago, pocster said:

Yeah I’ve tried getting the installer to go with me . I did consider a complaint - though of course DNO might win . A dc battery zero hassle and cheaper I guess .

Have you considered just doing it? Configure it properly and within realms of what DNO would want and crack on. 

 

I could not professionally make this recommendation obviously but what is stopping you? There is no DNO police.

 

There, I have thrown the written hand grenade.

[Pocster]

Just now, Carrerahill said:

Have you considered just doing it? Configure it properly and within realms of what DNO would want and crack on. 

 

I could not professionally make this recommendation obviously but what is stopping you? There is no DNO police.

 

There, I have thrown the written hand grenade.

Prison , humiliation , shame - I can’t bare those !