TIC and DNC

[19simon]

Bit of a newbie question

Have installed 17 x 250w Hyundai panels in sub optimal position on sw and se facing roofs. Have a Fronius IG3.6TL inverter to limit output to 16a.

SSE (who were supplier to last 2 installs) dont ask for TIC, only DNC so was planning to put 3.6 on DNC box. Npower ask for TIC. What do I put in that box?

Thanks

 

[GaryM]

Would that not be 17x250 = 4.25kW?

 

[19simon]

Thats what I thought. That wont get me into any trouble on the FIT form will it.

 

[TedM]

99.9% of PV installations are registered with OFGEM as TIC = DNC. If you read the definitions then you may see why.

The FiT band is based on the TIC - so if you put 4.25 then you will only qualify for the 37.8p rate.

 

[19simon]

I thought the definitions would allow me to put 3.6kw for both. If I put 4.25 kw for tic then I'm opening up the possibility of requests for clarification or rejection from fit provider either of which will ensure we miss the deadline!

 

[TedM]

I agree. Your TIC and DNC are both 3.6kW.

 

[whlphil]

Thats not what we were told by OFGEM they have stated that TIC is the nameplate rating of the fuel source which is the panel @STC, quite correct in that DNC is output terminal of inverter (although some DNO's will try to argue otherwise).

I do know of at least one installer who is getting round the TIC by speccing panel with wide tolerance +/- 10% but having the manufacturer grade the panels and only give him the +10% and them installing a 4Kw system on TIC that is actually 4.4kw.

 

[TedM]

OFGEM's own legal definition of TIC includes the magic word 'Installation'. Without an inverter a PV system is not a complete 'Installation'. The panels alone will produce DC V - but so what? Therefore the inverter has to be part of the "Installation" and therefore the inverter output has to be the TIC.

As I say 99.9% of existing installs use the definition where TIC = DNC.

One of many long discussions of this here: How is PV installation size defined for FIT purposes