Solar Panels?

[gazapc]

BREMBOV6 said:

Thanks to the previous help on solar panels. Currently in the process of buying a house with them. I have found out the following information -

Fitted in 2011
Certified - Phono Solar Technology
Estimated Annual kWh Generation - 1339.00
Declared Net Capacity kW - 1.56

Not shown everything but this on the installer certificate. This is our opportunity to go back to the solicitor to ask any questions before missives. Somebody kindly mentioned FIT payments. Any other advice would be great!?

Yes make sure the FIT transfer is included in the sale contract.
Ensure you get a copy of the "MCS" certificate for the system (not clear if this is the 'installer certificate' you mention.
Note that 1.56 kW is a pretty small system, but with the high FIT for 2011 you will get some revneue. Ofgem do however allow you to add more and keep the existing FIT if that interests you in the future.

markiii said:

tell me more about these optimisers?

Here is a good (albeit not 30 second) summary
https://www.youtube.com/watch?v=9GvhDhCSJgo&t=...


They can help, but if you have a well design system already with minimal shading, retrofitting won't make much difference.

[markiii]

I'm surprised retrofitting doesn't affect the FIT as the contract states no changes post certification

[gazapc]

markiii said:

I'm surprised retrofitting doesn't affect the FIT as the contract states no changes post certification

As a result of a consultation last year Ofgem made various changes.
https://www.ofgem.gov.uk/sites/default/files/2021-...

[markiii]

interesting but makes no mention of domestic power levels, seems to be aimed at the commercial producers

[gazapc]

markiii said:

interesting but makes no mention of domestic power levels, seems to be aimed at the commercial producers

The FIT was applicable for domestic and commercial solar installations up to 5 MW. The changes apply to all.

[markiii]

domestic was capped at 4Kwh,

that doc makes no mention of that limit needing to be maintained it only talks about the 5MWh

[gazapc]

markiii said:

domestic was capped at 4Kwh,

that doc makes no mention of that limit needing to be maintained it only talks about the 5MWh

No it wasn't. You could install a domestic 10 kW (not kWh) system if you so wished. What was different was the specific tariff rate at different system sizes so people made an economic decision to do so.

Please re-read amendment 6.7, 6.11, 6.15 in particular which all refer to the original tariff rate being maintained. The reason they don't mention the 4 kW tariff band is because it is not relevant.

The FIT programme and legislation behind it was applicable from 0 kW up to 5 MW for solar. Their definition of TIC, installation etc... applies to any size installation within this range. The cap has always been 5 MW.

[markiii]

I'll rephrase 4Kw was the max domestic install allowed without special permission from the supply company

my FIT contract states no more than 4KW

[Evanivitch]

markiii said:

I'll rephrase 4Kw was the max domestic install allowed without special permission from the supply company

my FIT contract states no more than 4KW

3.6kW was the maximum permitted export. I'm not fully aware of the rules at the time, but quite sure you could have had 10kW generation but needed evidence it would only export 3.6kW at peak to grid.

[gazapc]

markiii said:

I'll rephrase 4Kw was the max domestic install allowed without special permission from the supply company

my FIT contract states no more than 4KW

Not to labour a point but 1) the DNOs who impose the 3.68 kW limit have nothing to do with the FIT 2) the "Supply company" administer the FIT payments, you don't get permission from them 3) you can comfortably go above 4 kW (module capacity) on a 3.68 kW grid connection as you oversize. The reason why households didn't was because the FIT tariff reduced at this point.

As noted in the Ofgem response I linked to, they amended the existing FIT T&Cs to permit extensions. It is a great opportunity for those with existing systems.

Evanivitch said:

3.6kW was the maximum permitted export. I'm not fully aware of the rules at the time, but quite sure you could have had 10kW generation but needed evidence it would only export 3.6kW at peak to grid.

For FITs not quite correct. The tariff bands were based on module capacity, so your 10 kW system would attract a lower tariff.
However you are correct now that DNOs only look at the AC power (3.68 kW as standard).

Edited by gazapc on Thursday 20th October 15:54

[KTF]

I have had my solar together quote (Infinity Renewables) come through.

Annual consumption 3384kWh

10 panels = £6952.

Battery options.
3kWh = £2920.
4.6kWh = £3815
9.2kWh = £4790
No mention of any brands.

No idea if this is good/bad as none of the other companies I have contacted have even bothered to do anything.

[NMNeil]

KTF said:

I have had my solar together quote (Infinity Renewables) come through.

Annual consumption 3384kWh

10 panels = £6952.

Battery options.
3kWh = £2920.
4.6kWh = £3815
9.2kWh = £4790
No mention of any brands.

No idea if this is good/bad as none of the other companies I have contacted have even bothered to do anything.

Be careful choosing batteries, there's many suppliers of pre built battery packs who use grade B cells and cheap BMS.
Look for ones that use new CATL or EVE cells. If the battery maker won't tell what cells they use, walk away.
But 3800 quid for a 4.6Kwh battery pack seems expensive.
$1,500 (1,300 quid) for 5.1Kwh is the norm.
https://signaturesolar.com/eg4-lifepower4-lithium-...

[Chris Type R]

gazapc said:

As noted in the Ofgem response I linked to, they amended the existing FIT T&Cs to permit extensions. It is a great opportunity for those with existing systems.

Isn't it a potentially long winded bureaucratic process ? It's a struggle to deal with any FIT billing queries, so finding someone with sufficient knowledge at the FIT licensee would be the first hurdle. The upgrade would almost certainly need to be done by someone qualified and require forms and chasing people etc and the outcome is receiving a pro-rata payment.

Isn't this only worth pursuing if you have limited roof space to add more panels ?

Tell me if I'm wrong, because it is something I've given thought to... it would be handy to replace my 2kWp panels with a 4.45kWp install for example. I do have roof space to add an East and a West array to lengthen the generation day, as well as a little more space to add about 2kWp more of South facing - while leaving the FIT array undisturbed.

[gazapc]

Chris Type R said:

Isn't this only worth pursuing if you have limited roof space to add more panels ?.

It could also benefit those with lots of space above what a system currently occupies (like your install based on your description) You don't even need to rip out the old panels then.

And agree that the admin side might be slow until licencees get up to speed with this still relatively new change.

[dmsims]

NMNeil said:

$1,500 (1,300 quid) for 5.1Kwh is the norm.
https://signaturesolar.com/eg4-lifepower4-lithium-...

They will not ship to the UK but your point is valid about prices

[Chris Type R]

gazapc said:

Chris Type R said:

Isn't this only worth pursuing if you have limited roof space to add more panels ?.

It could also benefit those with lots of space above what a system currently occupies (like your install based on your description) You don't even need to rip out the old panels then.

If you're keeping the old panels you can simply install as a separate system and register for SEG. I think it's only worth going down the pro-rata rabbit hole if you want to or need to replace old panels.

ETA: there is one person who I'm aware of on MSE who has managed to set up a pro-rata system.

[NMNeil]

dmsims said:

They will not ship to the UK but your point is valid about prices

Based in Spain, they sell batteries and they even have a kit to build your own.
https://www.youtube.com/watch?time_continue=7&...
SOK have a European outlet, not sure where in Europe.
https://www.europe.sokbattery.com/product-page/sok...
In the UK, but a touch expensive
https://dcguy.co.uk/server-rack-battery
A bit basic for my taste, but UK based and not too pricey.
https://www.sunshinesolar.co.uk/Item/DLI48100
Just google 'server rack battery UK"

[Enut]

TriumphStag3.0V8 said:

OutInTheShed said:

2kW is a lot to get rid of with just a few heatsink fins.
You'd need a lot of fins and good passive airflow.
Efficiency below about 90% seems quite unlikely to me unless something is badly wrong.

I would imagine the system is measuring at least one of the powers wrong and hence calculating some others wrong.


The fact that the numbers seemed to add up exactly is suspicious for a start.
Sometimes you can get the wrong answers measuring volts and amps to get power, AC has phase and harmonics to think about, what's supposed to be DC has AC components added, and v/v.

I could speculate about stuff to measure, but googling for other people with similar issues might be more constructive.
Wild guesses might include a calibration factor being set wrong in the software.

If I was the installer I might be doing some RTFM this evening.

Power conversion systems are somewhere between 'interesting' and 'dark art'. My own relatively minor involvement with this branch of electronics has had its moments....

We had a smart meter fitted after the solar install - long story short, the smart meter guy connected the solar panel clamp on the incoming feed incorrectly and everything was displaying incorrectly (or 4.8kW system was producing over 7kW, the house that was using around 300W before he touched anything was suddenly drawing about 4kW etc). He was adamant that it was correct and I would need to speak to the installer.
Fortunately I had taken pics before and was able to point out that the cables were not in the same places - which he remedied and everything was good again.
So - it sounds like something is not wired up correctly for you.

Well the electrician arrived yesterday and brought the last battery so I now have 4 batteries and 12.8 KW of storage. I showed him the eroneous power consumption readings when feeding back into the grid and he had no idea what was going on, he got their technical manager to phone me and his advice was 'let's leave it over the weekend and see if it settles down!' They don't instil a lot of confidence.

By the way I mentioned about the clamp possibly being the wrong way round and reading incorrectly but he assured me it was all working correctly.

[TriumphStag3.0V8]

Enut said:

TriumphStag3.0V8 said:

OutInTheShed said:

2kW is a lot to get rid of with just a few heatsink fins.
You'd need a lot of fins and good passive airflow.
Efficiency below about 90% seems quite unlikely to me unless something is badly wrong.

I would imagine the system is measuring at least one of the powers wrong and hence calculating some others wrong.


The fact that the numbers seemed to add up exactly is suspicious for a start.
Sometimes you can get the wrong answers measuring volts and amps to get power, AC has phase and harmonics to think about, what's supposed to be DC has AC components added, and v/v.

I could speculate about stuff to measure, but googling for other people with similar issues might be more constructive.
Wild guesses might include a calibration factor being set wrong in the software.

If I was the installer I might be doing some RTFM this evening.

Power conversion systems are somewhere between 'interesting' and 'dark art'. My own relatively minor involvement with this branch of electronics has had its moments....

We had a smart meter fitted after the solar install - long story short, the smart meter guy connected the solar panel clamp on the incoming feed incorrectly and everything was displaying incorrectly (or 4.8kW system was producing over 7kW, the house that was using around 300W before he touched anything was suddenly drawing about 4kW etc). He was adamant that it was correct and I would need to speak to the installer.
Fortunately I had taken pics before and was able to point out that the cables were not in the same places - which he remedied and everything was good again.
So - it sounds like something is not wired up correctly for you.

Well the electrician arrived yesterday and brought the last battery so I now have 4 batteries and 12.8 KW of storage. I showed him the eroneous power consumption readings when feeding back into the grid and he had no idea what was going on, he got their technical manager to phone me and his advice was 'let's leave it over the weekend and see if it settles down!' They don't instil a lot of confidence.

By the way I mentioned about the clamp possibly being the wrong way round and reading incorrectly but he assured me it was all working correctly.

Yeah, that's exactly the conversation I had with the meter engineer - give it 24 hours and see if it settles down...... errr, no.
I stood my ground and wouldn't let him leave until he at least tried to fix it.
He also told me all the cabling was correct and was adamant about it until I showed him it wasn't. When the cables were then connected correctly the readings were right immediately.

Keep on at them. Something is not wired up right!

[gazapc]

Chris Type R said:

If you're keeping the old panels you can simply install as a separate system and register for SEG. I think it's only worth going down the pro-rata rabbit hole if you want to or need to replace old panels.

ETA: there is one person who I'm aware of on MSE who has managed to set up a pro-rata system.

Another scenario is if you are installing a BESS system at the same time as adding solar and want to retrofit a larger hybrid inverter.