Solar Together Kent - Good scheme? Good quote for a 12 panel system? [AVOID]

Martyn1981

adamdynamic said:

Solar Together can guarantee an output of 300 watts from one solar panel. 

In order to ensure the quality of the solar PV systems that are offered through the group-buying scheme, Solar Together demands a minimum set of warranties that have to be offered by the suppliers that participate in the auction. These warranties include: 

Warranty on Power Output

This is guaranteed by the manufacturer of the solar PV panels. The power output of the solar panels needs to reach more than 90% of its maximum (Watt-peak) in the first ten years and needs to reach more than 80% of its maximum in the next 15 years. 

^ I heard back from the company earlier today and this is what they said, so I'm assuming Wp per panel is 300 x 90% = 270 Wp and for an array of 12 panels is 270 X 12 = 3.2kWp?

Or the panels will give 300W at 90% so they are 333Wp?
Have to be honest, this is all very confusing. I think you need them just to clarify the total system size, and that the 4,050kWh pa takes into account the fact that your rooves are not south facing.
Hope it doesn't seem like we are all being difficult or picky, it's just that it's hard to come to any conclusions when the info you have been given is a tad vague.
The good news however is that for a 12 panel system with 'decent' sized panels, let's say 300Wp+ is OK. But the higher the panel rating is, the more the deal move's from 'Meh!' to 'Nice!'.

ABrass

They're a group buying scheme, which means they'll get whatever is cheapest at the time as long as it hits certain benchmarks.

One of those benchmarks is a 300W panel (or better) another is that those panels will be rated for 90% output after 10 years.

adamdynamic

Martyn1981 said:

Or the panels will give 300W at 90% so they are 333Wp?

Have to be honest, this is all very confusing. I think you need them just to clarify the total system size, and that the 4,050kWh pa takes into account the fact that your rooves are not south facing.
Hope it doesn't seem like we are all being difficult or picky, it's just that it's hard to come to any conclusions when the info you have been given is a tad vague.
The good news however is that for a 12 panel system with 'decent' sized panels, let's say 300Wp+ is OK. But the higher the panel rating is, the more the deal move's from 'Meh!' to 'Nice!'.

Hexane said:

Their wording seems to vary between unusual and meaningless. Ignore the power output warranty (it's not unusual but it's not very meaningful either), these are 300W panels. (I suspected that.) So at £4K for a 3.6kWp system, it's not actually a bad deal although not a particularly great one either.

Agree that the wording is ambiguous and difficult to draw conclusions from. I asked here because I thought it might just me me as a first-timer; reassuring to see that more experienced heads are struggling with it as well

I'll go back and ask whether the 300W rating is before or after the "90% efficiency" is taken into account (good question, one I hadn't thought of). I'll also see if I can get a straight answer to the "what is the system size?" question.

From a "buying decision" perspective, I would need it to be more towards the "nice!" end of the spectrum rather than merely "meh". The requirement to pay GBP 150 up front annoyed me before I even posted here, so if the deal is not materially better than I could get by going direct somewhere, I'd prefer to shop around and take my time rather than being rushed into a 11 December deadline.

Thanks again for everyone's help!

Solarchaser

So 300w x12 panels will not generate 4mwh a year, unless you live on the equator.
Certainly won't do it in the UK.
My 4kw produces 3.3mwh in Scotland. 
Perhaps the South of England may see 4mwh out of a 4kw system pure South facing.

But you don't have pure South facing, and you don't have 4kw.
I'd think around 2 - 2.5mwh a year would be more realistic from your split 3kw system.

In short, the company is lying and exaggerating their figures, so for me, id walk away and flip them the fingers while doing it.
Your first contact was a lie, trust is gone.

2 years ago I bought 22 x 300w panels for around £2k as a private buyer, not a bulk buyer.
I made a railing system from old deck boards, but if we assume you would have to buy a proper rail system, a spark to wire it up, some scaffold to get them to the roof, im still at £3k at absolute max for a 3kw system.

And the proposal is this is a community buy, bulk savings in everything surely, so I'd expect a 15%+ discount, so £2600 or so would seem right to me

Martyn1981

Adam, I have to agree with Solarchaser if those assumptions are correct. If we read the 300Wp assurance as 300Wp, then 3.6kWp will never come close to 4MWh pa in an off south Scottish install. And therefore sadly, trust has been lost, and you need to take great care.

Playing Devil's Advocate, however, if the panels companies have to offer, under the scheme, are at least 300Wp, and the 4,050kWh figure has been correctly calculated based on the actual system size, and the orientation, then I'd say it's a pretty decent deal. [I remain slightly optimistic, as I believe there are rules companies have to follow when calculating annual generation estimates, so hopefully it hasn't just been made up!!!!!]

Looking at these two extremes, you can probably see why the first response (from Eric) was so apt.

Fingers crossed when you get more info, assuming you can, it will all become clearer and for the better. Perhaps the simplest way to look at this, is that a system that can fairly be predicted to generate 4,050kWh pa on your rooves, would be good value at £4k.

Most of us on here use PVGIS to get a very good guesstimate of annual generation. If you have a play, you'll get to see what size system would be needed for 4,050kWh at your location (probably over 5kWp).

Exiled_Tyke

Sorry but the more I read of this the less I like it. I can't trust an organisation that gives vague hyped up sales spin. But ultimately for me, I never ever trust a seller who tries to pressurise by setting unnecessary deadlines.  Personally I'd run!

ASavvyBuyer

Exiled_Tyke said:

Sorry but the more I read of this the less I like it. I can't trust an organisation that gives vague hyped up sales spin. But ultimately for me, I never ever trust a seller who tries to pressurise by setting unnecessary deadlines.  Personally I'd run!

I agree, they seem to be being very vague with their information and pushing for agreement.

A genuine deal would give clear information on exactly what you would be getting for the price offered.

Solarchaser

Haha well spotted Mart, 3x12 is 36, not 30 as I seemed to calculate.... im supposed to be good at maths too 😳

I like your optimistic approach that they have contacted Adam with his specific house and gen in mind, I hope you are right tbh, that would somewhat restore my faith in humanity.

My pessimistic/cynical approach is that they batch fired a load of leaflets round anyone in Adams general area.

I'd honestly like to be wrong.
Solar has unfortunately had more than its fair share of cowboys 🤠 

Hexane

Martyn1981 said:

Adam, I have to agree with Solarchaser if those assumptions are correct. If we read the 300Wp assurance as 300Wp,

Actually I've flip-flopped on this, and I now think your guess of 333W panels (with a 90% performance guarantee giving 300W) might better explain the odd wording. It's a very strange way of putting it of course (I have various pieces of paper about what efficiency my panels are supposed to have over certain periods of time, but I still call them 315W panels not 291W guarantees because that's what they are) but it would mean a 3.99kWp system for £4K which is not bad.

then 3.6kWp will never come close to 4MWh pa in an off south Scottish install,

I think the proposed installation is in Kent, not Scotland. Second sunniest county in England perhaps? So 3.99kWp might do it...

I also, again, think this is a "one-size-fits-all" not-a-quote so their figures are based on what would be possible with a fully south-facing 12-panel solution maybe based on PVGIS from the centre of Kent. Which means their invitation to put down a £150 non-refundable deposit to actually get a proper quote (based on actual roof orientation etc.) should be politely declined.

Still far better than that well-known company who used to advertise on the front pages of major broadsheets offering a similarly sized system for two or three times more on the basis that it included "voltage optimisers" or something. (Was it Project Solar?)

Petriix

Get some other quotes from local independent installers. My 3.42kWp system cost £4150 in 2017 and prices per panel have come down since then. 4kWp should cost under £4k. And definitely don't get the battery: even if you cycled it once per day, it would only save you £1500 in 10 years.