Solar PV Quotes Northants

Meatballs

I've looked at a few desktop quotes for my install over 3 roofs, one south, one east one west facing. All using SolarEdge with optimizers:

Comp1
£11500 for 16 Sunpower 400w panels 6.4kWp (1.796£/W)
£14500 for 22 Sunpower 400w panels 8.8kWp (1.647£/W)

Comp2
£8800 for 12 Q Cells 385W- 4.62kWp (1.731£/W)
£11388 for 12 Sunpower 400w - 4.8kWp (2.372£/w)

Comp3
£12000 for 21 JA Solar 330w Panels  6.93kWp (1.731£/W)

Obviously a way off for £1/w on all quotes so far. I do quite like the SunPower ones to maximise the roof usage and the efficiency/guarantees that come with them, but are all installers that use them fairly premium price? Should I shop around for some more quotes? None of these currently include bird guards but I think that will definitely be required!

Hexane

Wow! Well, I will start by saying I have no idea what a "desktop quote" is. And then... oh wow, that looks so expensive.

Why are you using this "desktop quote" thing when it seems to be designed to make you pay 50% more than you should?

Did you talk to any local installers? What did they say?

ABrass

Hexane said:

Wow! Well, I will start by saying I have no idea what a "desktop quote" is. And then... oh wow, that looks so expensive.

Why are you using this "desktop quote" thing when it seems to be designed to make you pay 50% more than you should?

Did you talk to any local installers? What did they say?

It's when they do a quote from their desks. IE they look on Google maps.

I'd be continuing to look as at those rates I'm not sure you'd ever break even.

arty688

I would say the comp 1 was ok as you do pay through the nose for sunpower. The other 2 quotes seem very expensive. Comp 3 should be nearer £1/W as it’s bottom end panels. I’d be interested to know what the companies the quotes are from?

arty688

Also with Solaredge optimisers you will never get near to the £1/W anyway , but roughly the ha panel will be £200-£250 cheaper than the sunpower so should comp 3 should be at least £4K cheaper in panels.

QrizB

Those Sunpower panels seem to be around £300 each, so that's 75p/watt in panel costs before looking at the rest of the system. Comp1's quotes can be thought of as £6700 + 16 panels or £7900 + 22 panels.

385 watt JA solar panels are £140 each so substituting those into Comp1's quotes would give £8940 for 16 panels (£1.45/watt) or £10980 for 22 panels (£1.30/watt).

It's obviously your choice whether the premium for Sunpower panels is worth it, or not. Ditto SolarEdge and optimisers, vs. three  strings with conventional string inverter(s) to suit. I'm assuming both were an active choice on your part.

I'm not at all impressed by Comp3 offering 330w panels for your setup, especially as the price per watt ends up so high!

Meatballs

QrizB said:

Those Sunpower panels seem to be around £300 each, so that's 75p/watt in panel costs before looking at the rest of the system. Comp1's quotes can be thought of as £6700 + 16 panels or £7900 + 22 panels.

385 watt JA solar panels are £140 each so substituting those into Comp1's quotes would give £8940 for 16 panels (£1.45/watt) or £10980 for 22 panels (£1.30/watt).

It's obviously your choice whether the premium for Sunpower panels is worth it, or not. Ditto SolarEdge and optimisers, vs. three  strings with conventional string inverter(s) to suit. I'm assuming both were an active choice on your part.

I'm not at all impressed by Comp3 offering 330w panels for your setup, especially as the price per watt ends up so high!

I'm likely to get a bit of shading from the roof layout and chimney stack, so the optimizer route seemed sensible and results in just the one inverter to install (and potentially replace) over the life of it. Would it be more competitive to have an inverter per string? I haven't seen any offerings of microinverters.

QrizB

I'm a very simple soul   but to my mind the default for a three-aspect roof woulkd be three separate strings, each feeding one of 3 inverters (or, potentially, separate inputs on 1 or 2 inverters). I would expect any installer to offer this as a default option and only add optimisers or microinverters to the mix if the installation required it, and also to explain to the customer what the costs and benefits of this would be.

But then I'm not a solar installer, I might have entirely the wrong idea about that. The two arrays I've had installed have both been pretty simple, south facing roofs with no significant shading, so optimisers and microinverters never really came into it.

Regarding microinverters, I did notice while Googling that Sunpower offer a range of panels with integrated Enphase microinverters. I can't find a UK price but this French site quotes E460+VAT. You could ask one of your quoting companies to give you a price for this instead of the SolarEdge option? (I don't have an opinion on Enphase vs SolarEdge, they both seem like decent premuim products.)

QrizB

PS: I'm not trying to put you off, I'm really not. I'm just working through why your quotes look quite high. It seems mostly due to the premium components you've chosen / been offered.

Meatballs

No worries, I've sent a few more requests out to get a wider range of quotes and hopefully see some more variation!

arty688

Other things to look into are

tigo optimisers these don’t have to be installed on every panel.

Make sure the inverter is under sized . Especially as your set up will never get anywhere near the max output.

If your heart is set on top notch panels look at LG and Panasonic as well.

panel size plays a part too take the above ja 385w is bigger than the sunpower 400w so you may not get 22 on your roofs.I think sunpower have the best W per m2 it if they will produce £200 of electricity over their lifetime might be worth calculating.

optimiser vs micro inverter confuses me a bit but I have decided on micro inverters I think. As they work better in low light conditions and don’t have a single point of failure. But there’s not much in it.