4kw & FIT rates

[moggy1968]

there are a few DNOs I believe that will now allow 4kW under G83, sadly not the one I have to work with!
The G83 requirement is based on the output of the SYSTEM, not the panels, which is why a 4kW set of panels with a 3.6kW inverter is fine. the DNO should take the lower output of the two as the system output. by the same token if for some bizzare reason you put 3.6kW of panels on a 4kW inverter that would also be ok under G83.

Multiple installations in the same post code (which is what I meant by immediate area, although I don't know if it could extend beyond that to any house served by the same transformer) do require notification, for the same reason as larger scale installations, in order for the DNO to assess if the local network is being 'overloaded' with back feed for the same rather feeble reasons they have to approve installations over 4kW.
As such if you, say, did multiple installations on the same street (like a certain firm me and yellowvanman know!) the DNO could come back retrospectively and ask for the systems to be switched off and ask for payment from someone (you or the householders!) to survey and possibly upgrade the electrical infrastructure.
Strangely doesn't appear to be a problem in Germany!!

 

[babba]

I know its a load of bull I like an easy life, spoke to loads of people and came to the 3.68 and thats it or g59 and hassle if all goes silly and I didnt fancy picking up the bill, anyway 15 panels is cheaper than 16 save the customer some money.

 

[SolarCity]

I know its a load of bull I like an easy life, spoke to loads of people and came to the 3.68 and thats it or g59 and hassle if all goes silly and I didnt fancy picking up the bill, anyway 15 panels is cheaper than 16 save the customer some money.

But surely you have considered installing 4kWp of panels on a 16A limited inverter?

 

[moggy1968]

I know its a load of bull I like an easy life, spoke to loads of people and came to the 3.68 and thats it or g59 and hassle if all goes silly and I didnt fancy picking up the bill, anyway 15 panels is cheaper than 16 save the customer some money.

??????

 

[babba]

This was the dno advice at the time.
Single Installation up to 16 amps per Phase

 

[moggy1968]

In general, you will need our consent to connect generating equipment to our network. However, in the case of generating equipment rated at no more than 16 Amps per phase, consent is not needed, provided:

Which means you can connect a 4kW array with a 3.6kW inverter without consent because the max output is 16a

 

[babba]

Not the words I was told 3.68 max panels allowed and 16a inverter but thanks for the up date it will come in handy when my dno starts the black magic.

 

[SolarCity]

Your DNO has no say in it. You can put 10,000kWp of panels in as long as your inverter can only export 16A. Incidentally, as far as FITs are concerned, you can install 10,000kWp of panels as long as your inverter is still rated at no more than 4kWp.

 

[moggy1968]

really???
I was wondering about this as I put 17 235s on ahouse, split on a south and east roof. I had a spare panel and thought, well why not stick it on to maximise the output from the less than ideal orientation of one of the roofs but assumed as the panel capacity exceeded 4kW it would attract a lower FiT rate.
I think I posted on here about it and most people agreed.
this would be a way of making your 21p work better, put excess numbers of panels on to maximise your output under less than perfect conditions.
I do suspect it's not allowed though!

 

[babba]

O what a mine field the reason I dont step out of the box.

 

[SolarCity]

Absolutely. FITs are based on TIC which totally depends on output from the inverter instead of the amount of panels fitted on the roof.

 

[Gavin A]

Your DNO has no say in it. You can put 10,000kWp of panels in as long as your inverter can only export 16A. Incidentally, as far as FITs are concerned, you can install 10,000kWp of panels as long as your inverter is still rated at no more than 4kWp.

current argument I'm having with EDF for a 4.25kWp installation limited to 3.68kW output. For some reason the customer had filled in their own fit form, and put the TIC as 4kW and the DNC as 3.68kW which obviously got EDF's attention, and they sent an email asking for the details of the panels fitted, array size etc.

The customer stupidly rang them today instead of waiting for me to deal with it (less than 2 hours after they first emailed me about it, while I was on site) and ended up getting their installation moved to the above 4kW FIT band by an EDF manager who apprently seemed to think that an inverter couldn't limit the output in that way...

Hopefully the email I just sent should sort it out, but it's a hastle I could do without right now.

 

[SolarCity]

I'd be interested to hear how you get on with that.

Installing more than 4kWp of panels has always bothered me for this very reason. Is it something that you have done a lot?

 

[dansk]

O what a mine field the reason I dont step out of the box.

Pretty clear really, Np is my DNO also and we have never had a problem.

 

[moggy1968]

if you don't know whats achievable then you may be losing yourself business and, more importantly, not delivering the best solution for your customer. The 4kW/3.6kW thing is quite fundamental and been discussed a few times on here before.

 

[babba]

Its all good cheers for the input men Its ok I will be staying inside my box. At the moment uk power networks are ok with 4kw on 4kw inverter.

 

[SolarCity]

When you say "4kW on 4kW inverter", it makes me wonder if you understand the difference between FITs and DNO requirements.

The DNO wants anything above 16A to be pre-notified.

Suppliers pay FIT based on TIC which is the output of the system. This can be an inverter that outputs 4kW with panels of, say, 5kWp.

It is none of the DNOs business how many panels you put on your roof. The 16A limit is the only think you need worry about.

 

[babba]

so sma 4000tl is fine on 4kw of panels all over the uk on probs with any DNO for G83..???

 

[SolarCity]

No, of course not - unless the DNO accepts the inverter being limited at 3.68kWp.

 

[babba]

Ye but you can limit the 4000 to 16A