Adding a new array to a property with an existing array

jimmyboy420

I have 4kW on the front my my house (South East)
I'm considering the possibility of adding 4kW on the back of my house. (North west).

I realise this won't perform as well due to orientation, but it is subject to less shading, which works in its favour. I'd probably do this after I've had a chance to take a look at how the sun shines on it in the winter.

But I was wondering how does the FIT work?

Is it considered two separate 4kW installs? Does it become necessary to start considering measuring export directly (rather than assumed 50%)

I know that a couple of people on here have multiple installs - just after some info about any pitfalls really.

Thanks
James

Martyn1981

jimmyboy420 wrote: »

But I was wondering how does the FIT work?

Is it considered two separate 4kW installs? Does it become necessary to start considering measuring export directly (rather than assumed 50%)

I know that a couple of people on here have multiple installs - just after some info about any pitfalls really.

Thanks
James

Funny you should ask ..... see section 10:-

"10. Adding to an existing PV system, or adding an additional PV system at the same address."

of the PV FAQ.

https://forums.moneysavingexpert.com/discussion/comment/57831489#Comment_57831489

NB: EPC on or before commissioning date if you don't already have one.

Best of luck.

Mart.

Martyn1981

jimmyboy420 wrote: »

Does it become necessary to start considering measuring export directly (rather than assumed 50%)

Up to you. If you can get an export meter fitted for free (most will charge) then you might want to go for it, but depends if you run a diversionary switch.

Export meters are only compulsory on systems of 30kWp and upwards.

Quick thought, when was your original system installed? If prior to Aug 12, then it'll be on a lower export rate, so presumably 'a right pig' to work out.

On a similar theme, I assume you'll want to run the second system through a separate TGM, otherwise generation will apportioned by kWp, with no regard for orientation. That'll effectively shift SE units onto the NW tariff. Beware.

Mart.

jimmyboy420

Martyn1981 wrote: »

On a similar theme, I assume you'll want to run the second system through a separate TGM, otherwise generation will apportioned by kWp, with no regard for orientation. That'll effectively shift SE units onto the NW tariff. Beware.
Mart.

Thanks! This is the sort of thing I was interested in. I read the part in the FAQ now too.

Something that's not quite 100% clear, is how the FITs tarriff for the existing tarriff will be effected. Will it drop in line with the higher rate when I get another install, or is that part fixed, and only the new install effected by the tarriff banding?

Thanks!

James

Martyn1981

jimmyboy420 wrote: »

Something that's not quite 100% clear, is how the FITs tarriff for the existing tarriff will be effected. Will it drop in line with the higher rate when I get another install, or is that part fixed, and only the new install effected by the tarriff banding?

Thanks!

James

Hiya James. See para 4. The old FiTs is safe, so long as you don't change its kWp (you can of course replace faulty panels, inverter etc, but mustn't change the registered size of the system).

When I send in my TGM readings, I now have two codes. They are the same except one ends in xxx-1 (for the original TGM) and the other in xxx-2 (for the new TGM), so effectively an extension of your existing FiT contract.

The payments may arrive together, or a few days apart, but the remittance always calculates/lists them separately, with their respective FiT and export rates.

[Edit: Obviously you need to contact your FiT provider and ask them all of this. Double check everything. I'd suggest doing it by e-mail (rather than phone) so you have a record of their answer/instructions. If they say anything different, let me know so that I can update/amend the FAQ advice. M.]

Mart.

tunnel

I send in 3 separate readings for mine as I have 3 different tariffs (long long story) if you can get a good deal on the extra array then its well worth considering especially for you for the late evening sun in the summer.

Incidendly Mart, I don't get a remittance advice from my FiT provider, just a cheque for whatever amount is due. I do work it out to the penny though.....just in case, as you know my situation you'll know I won't let them off for even a penny:D