Additional Installation

Hobbo2006

Hi All,

I currently have a 4kW system split over two side of the roof.
11x 250w panels facing due west and 5x 250w facing due east.
I'm getting the original tariff so don't want to mess with that for obvious reasons.

I always regret not trying to go beyond the 4kW and just putting as many panels on there as possible.

I now have 1st refusal on some cosmetically damaged panels. Still in working order and fine for me. I'd have them fill the space on the roof, wired and connected to a separate inverter.

Is it worth registering them again under the latest FIT?
Can they connect to the Consumer unit?
Would that affect my original installation?

Thanks,

Richard

Martyn1981

Check out section 10 of the PV FAQs.

As long as you don't alter the original install, then its FiT won't be affected.

To connect to the CU (and therefore potentially export) you will need prior DNO approval if the sum of your inverters exceeds 3.68kW.

[Edit: I mentioned exceeding 3.68kW since there's a 4kWp install already. However, even if the addition of an extra inverter doesn't bring the total to more than 3.68kW, you would still need to notify the DNO afterwards. I was simply pointing out that PRIOR permission is needed for 3.68kW+. M.]

Mart.

Hobbo2006

Thanks Mart,

So if I understand the FAQs correctly I can't connect panels to the consumer unit, and therefore use the electricity in the house, without registering a new installation?

So change of question..... what's the best way to utilise 6-7 "free" panels? I realise I'll have to buy equipment/installation to actually get the best from these panels.

theboylard

All you need is a friendly installer who knows his onions.
Find one, get them to engage with the DNO (around here it's Western Power distribution) re going over the mythical/magical 3.68 capacity, as you're not going for double the size there shouldn't be any obvious reason for them refusing.

As long as the panels have not been used in a previous FiT install, then you should be OK for using them. Some installers won't touch kit they haven't supplied (ie no markup for them), others are happy to.

Martyn1981

Hobbo2006 wrote: »

Thanks Mart,

So if I understand the FAQs correctly I can't connect panels to the consumer unit, and therefore use the electricity in the house, without registering a new installation?

Yep. All grid connected generation (SSEG - small scale electricity generators) has to be registered with the DNO. They need to know so that they can do the maths, and ensure the local infrastructure is up to the job.

You don't have to go down the FiT route to do this, but your application will have to be by a qualified electrician. If you go that far, then probably best to go the whole hog and 'FiT' it too.

Hobbo2006 wrote: »

So change of question..... what's the best way to utilise 6-7 "free" panels? I realise I'll have to buy equipment/installation to actually get the best from these panels.

Basically, you're into the world of 'off-grid' with that. You could simply try to heat something with it, such as an additional input into a thermal store, underfloor heating etc.

Or you could go the whole nine yards, get some big deep cycle batteries, probably FLA's at this point, but watch out for Li-Ion coming up fast. Then you could use the batts to run a separate circuit in your house, perhaps fridge/freezer at night, lights since consumption is so low now etc etc.

But, you will need to research this properly, if for instance you want to run the freezer, then the inverter from the batts will have to cope with the meaty start up for a second or so. Perhaps provide power to an A/C unit as a heat pump, but again, you have high start up power.

Please don't listen too seriously to me about any of this, it's just stuff I've picked up nosing at various threads on the Navitron forum. I know very little, and it certainly seems like a subject that needs thorough research.

If you can, go for FiTs, I assume these are legit, new panels you are describing, even if they are cosmetically damaged. By the time you go down the off-grid route with charge controllers, inverters, batts etc then you may be spending as much on ancillary equipment as a FiT install.

Mart.

Hobbo2006

cheers guys,

very useful information as always. I'll get my thinking cap on.

Rich