Battery Storage recommendations

[Nickfromwales]

Run a 16a C form to the back of the garage / outbuilding hardwired into the house for petroL powered EPS, and just plug a second hand genny into that for the duration. 
 

Doomsday preppin’ gone mad here!!

[Thorfun]

1 hour ago, pocster said:

Yeah ! 80kw of storage !!!!

In my build I’d be hard pushed to justify more than 30kw of storage . 
Though I currently just have 13 ( pw2 ) and SE battery due May ( another 10 ) - I always consider the EV as ‘storage ‘ - so that’s an additional 54. 
If the SE seems good certainly plan to add another . Then I’ll be the winner ! ( don’t go and include your EV and upset me ) . What’s you pv generation? ( mine 4 but soon 7.2 ) 

I was only joking btw. I'm happy to let you win this one. 😉 

 

I have a 10.5kWp array so I think 4 x 3.3kWh batteries should suffice for me. the think I'm liking about using Pylontech batteries is if I need more capacity I can just chuck another battery in there to increase it. I like the modular aspect of it.

[RobLe]

I was the lucky recipient of a UPS a while back - a friend said it was bust & gave it to me ....it wasn't, it was his fancy PC all along.  Strangely, he lives up North near lots of power stations, but gets regular blackouts.  Anyway, it's 500W, £98, by Schneider, and claims to last 170mins with a 20W load.  I tried it with a power meter on the input and a mains fan as a load, and I'm surprised how good it is: 

Plugged in UPS no load, just trickle charge took 2.5W

fan running from mains took 22.3W

UPS + fan took 25.6W

Didn't miss a beat when turning the mains on/off, and seems pretty efficient in the usual "pass through".  Who knows how long it would actually last left on forever though.  I can't remember our last power cut here mind.

[Dillsue]

Having had the power off for 3 days over xmas in the 90s we've not been without a generator since. If youre on overhead line grid supply I think youd be nuts not to have a small back up generator. Predictions are storm intensity is likely to get worse and youve only got to look at what happened in the north of england/scotland a few weeks ago to realise that it takes time to repair storm damage leaving some people without power for weeks. With most storms happening in the winter when the suns not shinning theres a fair chance batteries may not be fully charged and very unlikely to keep the lights on for more than a day or two if the power goes off. £200 for a small genny seems a no brainer to me if youre on a vulnerable supply.

[TonyT]

3 hours ago, Nickfromwales said:

Run a 16a C form to the back of the garage / outbuilding hardwired into the house for petroL powered EPS, and just plug a second hand genny into that for the duration. 
 

Doomsday preppin’ gone mad here!!

 

exactly what I have

with changeover switch inside.

 

 

[Nickfromwales]

1 hour ago, Dillsue said:

Having had the power off for 3 days over xmas in the 90s we've not been without a generator since. If youre on overhead line grid supply I think youd be nuts not to have a small back up generator. Predictions are storm intensity is likely to get worse and youve only got to look at what happened in the north of england/scotland a few weeks ago to realise that it takes time to repair storm damage leaving some people without power for weeks. With most storms happening in the winter when the suns not shinning theres a fair chance batteries may not be fully charged and very unlikely to keep the lights on for more than a day or two if the power goes off. £200 for a small genny seems a no brainer to me if youre on a vulnerable supply.

 

38 minutes ago, TonyT said:

 

exactly what I have

with changeover switch inside.

 

 

I'll put you in the 'sane' camp  

Welcome.

[TonyT]

1 hour ago, Nickfromwales said:

 

I'll put you in the 'sane' camp  

Welcome.

Awesome, can I get a certificate to show my kids

[Russdl]

9 hours ago, Nickfromwales said:

I'll put you in the 'sane' camp  

Welcome.

I wonder if you’d care to elaborate on what you mean by that Nick.
 

[Nickfromwales]

9 hours ago, TonyT said:

Awesome, can I get a certificate to show my kids

Yes, lol. One for the mantelpiece .

 

[Dan F]

@Thorfun Have you looked at getting hold of a Powerwall yet?  What have you been told regarding lead time?

 

On 17/03/2022 at 12:20, andy said:

It's worth mentioning in case it hasn't been said but Powerwall install is zero-VAT rated as part of new build, so if you think you might need 3 then "cheaper" to get them all at once

 

Battery systems aren't on the governments list of "Energy-saving materials" and therefore technically can't be zero-rated.  This is also why they attact 20% VAT and not 5% (0% now) when retrofted.  I think what some suppliers are happy to do though, is consider the battery to be part of the of the PV system, and zero-rate it this way.

 

My PV installer is happy to zero-rate Powerwall(s) but has a very long 9mth lead-time.   I've found another supplier with better avaailbility, but they aren't happy to zero-rate 😞 

 

 

 

[Radian]

According to www.gov.uk subject to eligibility, batteries with solar installation should attract reduced VAT, i.e. zero now - I also think some of the other conditions are being relaxed but details are scarce at the moment.

 

Quote

Example
The installer is charged £3,500 for solar panels and battery (excluding VAT) and charges you £5,385 (excluding VAT) for the installation. As the value of the materials (the solar panels and the battery) is 65% of the total cost to you for both the materials and installation, it is over the 60% threshold. This means the installer will need to charge VAT for the solar panel and battery at the standard rate and the installation will qualify for the reduced rate of 5%.

 

[Thorfun]

1 hour ago, Dan F said:

Have you looked at getting hold of a Powerwall yet?  What have you been told regarding lead time?

yeah. was quoted 9 months lead time as well and also the price has gone up £2k in the last 18 months. As such, I'm now looking at a Lux Power Squirrel pod (2 actually) and Pylontech batteries as mentioned above. 

 

using 2 x squirrel pods gives up to a 7kW charge/discharge rate and each one can utilise 8 batteries so you can have a theoretical 56kWh of storage using the US3000C batteries. obviously, I won't be going that high, but I do like the modularity of this solution so if the initial battery storage isn't enough you can just add another battery to expand the system.

 

 

[Dan F]

2 hours ago, Radian said:

According to www.gov.uk subject to eligibility, batteries with solar installation should attract reduced VAT, i.e. zero now - I also think some of the other conditions are being relaxed but details are scarce at the moment.

 

The problem is they introduced a 60% rule in 2019.  So, unless the total materials cost is less than 60% of the total solar/battery install cost, it's not eligible.  If the guidelines are followed stictly, it's therefore unlikey that any powerwall install would qualify
 

I saw something about this 60% rule potentially being removed though,,

 

Edited March 24, 2022 by Dan F

[Dan F]

1 hour ago, Thorfun said:

yeah. was quoted 9 months lead time as well and also the price has gone up £2k in the last 18 months. As such, I'm now looking at a Lux Power Squirrel pod (2 actually) and Pylontech batteries as mentioned above. 

 

using 2 x squirrel pods gives up to a 7kW charge/discharge rate and each one can utilise 8 batteries so you can have a theoretical 56kWh of storage using the US3000C batteries. obviously, I won't be going that high, but I do like the modularity of this solution so if the initial battery storage isn't enough you can just add another battery to expand the system.

 

Have you looked at Sonnen?  Good battery technologies, extensible and they even have an all-in-one 3-phase solution, but I'm not sure it's available in U.K yet.  https://sonnen.de/stromspeicher/sonnenbatterie-10-performance/

 

 

[Thorfun]

4 minutes ago, Dan F said:

 

Have you looked at Sonnen?  Good battery technologies, extensible and they even have an all-in-one 3-phase solution, but I'm not sure it's available in U.K yet.  https://sonnen.de/stromspeicher/sonnenbatterie-10-performance/

 

 

yeah. looked at it. more expensive than the Powerwall 2 was my conclusion!

 

I'm not fussed about 3-phase solutions either as I'm planning on running the whole house on a single phase and already have a single phase inverter even though I have a 3-phase supply. if I get a 3-phase EV charger I'll just suck it up that I have to import on 2 of the 3 phases. 

 

I just think it's simpler that way!

 

and I'm also thinking that as battery tech advances if I have to I can swap out battery modules and replace with newer tech whereas with these all-in-one solutions you're kind of stuck with it.

[Nickfromwales]

4 hours ago, Thorfun said:

but I do like the modularity of this solution so if the initial battery storage isn't enough you can just add another battery to expand the system.

🤔. Your A/C coupled total ( kWp of PV + kWh of battery capacity ) needs DNO approval. If you add more down the line, you should be asking for a new approval. 

[Thorfun]

5 minutes ago, Nickfromwales said:

🤔. Your A/C coupled total ( kWp of PV + kWh of battery capacity ) needs DNO approval. If you add more down the line, you should be asking for a new approval. 

didn't realise storage needed approval as well as PV. why is that? it's not like the batteries will discharge to the grid, right?

[Marvin]

18 minutes ago, Nickfromwales said:

🤔. Your A/C coupled total ( kWp of PV + kWh of battery capacity ) needs DNO approval. If you add more down the line, you should be asking for a new approval. 

Or ask for approval for expected total amount of batteries and PV as it cost us £ 360.00 a time....

Edited March 24, 2022 by Marvin

[Nickfromwales]

12 hours ago, Marvin said:

Or ask for approval for expected total amount of batteries and PV as it cost us £ 360.00 a time....

All depends if that then gets you a refusal !

They may insist on export limitation on the PV inverter as a result of an over estimation on the battery capacity, so beware as that sword has two edges   

 

[Marvin]

43 minutes ago, Nickfromwales said:

All depends if that then gets you a refusal !

They may insist on export limitation on the PV inverter as a result of an over estimation on the battery capacity, so beware as that sword has two edges   

 

Good point!

[Pocster]

13 hours ago, Thorfun said:

didn't realise storage needed approval as well as PV. why is that? it's not like the batteries will discharge to the grid, right?

It doesn’t *always *
My pv goes through the gateway and exports at a max of 3.8kw ( my DNO limit ) . If I stick batteries on ‘that side ‘ then no matter my storage capacity I can only ever export 3.8kw . Therefore DNO don’t care and I could have a zillion giga watts of storage . Pw2 has an inverter integrated so can export on its own . So my DNO approved limit is my pv inverter max + pw2 max export .

[Pocster]

@Thorfun I think a lot depends on what your DNO does / doesn’t want . You have 3 phase so assume your DNO would limit your export per phase - but you do have 3 ! . Also like me you probably want to export little / nothing . You can ask to have zero export then you can fill your boots . The best solution I found was as much storage as I want but capped/limited export . Best of both worlds .

Your installer should be able to talk you through all this . I spoke directly to my DNO - she was super helpful- though I did turn on the charm 😁

[Thorfun]

Just now, pocster said:

@Thorfun I think a lot depends on what your DNO does / doesn’t want . You have 3 phase so assume your DNO would limit your export per phase - but you do have 3 ! . Also like me you probably want to export little / nothing . You can ask to have zero export then you can fill your boots . The best solution I found was as much storage as I want but capped/limited export . Best of both worlds .

Your installer should be able to talk you through all this . I spoke directly to my DNO - she was super helpful- though I did turn on the charm 😁

I've asked my M&E consultants if they included the originally planned PW2 with the DNO application for PV and am waiting to see what they say.

 

I'm not going the Tesla route anymore but will, most likely, be using a Lux Power AC coupled inverter so that will island the home/battery supply as I understand it.

 

I guess the problem is that I will be using my local friendly sparkie to do the install and not a battery installer. I'm sure I'll figure it out!

[Pocster]

3 minutes ago, Thorfun said:

I've asked my M&E consultants if they included the originally planned PW2 with the DNO application for PV and am waiting to see what they say.

 

I'm not going the Tesla route anymore but will, most likely, be using a Lux Power AC coupled inverter so that will island the home/battery supply as I understand it.

 

I guess the problem is that I will be using my local friendly sparkie to do the install and not a battery installer. I'm sure I'll figure it out!

Yep . If storage is ‘an island ‘ and restricted export then you are sorted . I went with pw2 originally as that was the main ( if not only choice ) . Also my original aim was to export as much as possible. But it became clear the last thing I want to do is export ! . I want to store as much as possible and when no sunshine fill storage as much as possible at tou cheap rate .

[Thorfun]

18 minutes ago, pocster said:

Yep . If storage is ‘an island ‘ and restricted export then you are sorted . I went with pw2 originally as that was the main ( if not only choice ) . Also my original aim was to export as much as possible. But it became clear the last thing I want to do is export ! . I want to store as much as possible and when no sunshine fill storage as much as possible at tou cheap rate .

phew! that's what I thought and I'm restricted by my 10kW Solaredge Inverter that the array is connected to and we have permission for and then the batteries will be on the house side of the islanding.