4kw & FIT rates

[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

 

[SolarCity]

Not exactly. You can limit the power output, not the current.

 

[BruceB]

Yes, that is irritating with the SMA inverters. There is no reason in principle the firmware could not limit the current as well as the power. It would be useful in this country as de facto we are mostly at 240V rather than 230V. A 4kW power limit (FIT) combined with a 16A current limit (G83) would be ideal. Any manufacturers listening?

 

[moggy1968]

no!!!!

 

[mdovey]

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

Isn't it the other way around -

TIC = Total Installed Capacity which would be the total capacity of the installed solar panels
DNC = Declared Net Capacity which would be the maximum output of the inverter

The FITs are based on TIC, the need for prior DNO approval is based on the DNC

 

[GaryM]

If FiT's are based on TIC then why does the British Gas FiT form I filled in lack TIC and only asks for DNC?
As it happens, mine was entered as 4kWp as that's what my MCS certificate said for DNC. My system is 16 x 250W panels and a 3.68kW inverter.