3-phase Solar PV quote

paddytt

Hi

We are considering a ground mounted PV system in our garden, and with our 3 phase supply we have been quoted c£17k + VAT for a 12KW system, with 42 x 8.33 285W panels and Enphase micros.

Is this a reasonable quote and any comments on the proposal?

thanks @ regards

paddy

Martyn1981

Hiya Paddy, gut reaction is that it sounds expensive as roof mounted PV heads towards £1k/kWp as you go bigger (perhaps 6kWp+).

Do you have a breakdown of costs? How much is the extra ground based costs - ground works, costs of frame (artificial roof effectively), and the labour for building said 'roof'?

You will find lots of information and advice on how to build a frame on renewables and off-grid sites, possibly from heavy duty tanalised wood, or secondhand scaffolding poles, however I don't know the rules on which the MCS qualification would be based, and whether DIY'ing this prep work is worth it for you. The use of 'ground screws' on large PV farms looks very simple and efficient, but I have no practical knowledge on what is the best choice for you ....... also assuming a purpose built out building isn't of use to you?

paddytt

42 x 285w panels £6k
42 inverters £4.8k
ground mount £3.8k
planning, design, install £2.1k

Martyn1981

paddytt wrote: »

42 x 285w panels £6k
42 inverters £4.8k
ground mount £3.8k
planning, design, install £2.1k

Hiya. Can't say much as I don't know about ground mounts, but the panel cost looks reasonable I think.

I'm not sure about the cost of the Enphase inverters, if you went with SolarEdge then you'd be looking at about £1,200 for the inverter (3phase 12kW-15kW) and about £40 each for the power optimsers, so that's about £2,880 + VAT, and those are retail prices. A SMA 3phase inverter of about 12kW will cost approx £2,500, again those prices are retail and before VAT.

Bit of googling and I've found some ground mount kits, which seem to be about £1k per 4kWp, so similar to the figures you have. As I mentioned if you are up for it, then scaffolding poles driven into the ground with some concrete could be a cheap option, or if you have use/need of a building, then perhaps a simple block built structure with one high side, and one low side. It probably won't be any cheaper, but at least you'll have a building too.

Sorry I couldn't really help, but all the best with your array.