Finding PV suppliers with skill, availability and stock? (... AND not outrageous prices?)

[puntloos]

For some reason PV seems to be an area where stock, availability and skill seems to all be more difficult than other areas. Anyone know why this is? Is it a bit of a 'wild west' area still, or are the weird incentive programs or unique stock issues running havoc with people? Or am I just unlucky?

 

Not sure if actual recommendations are allowed here, but if anyone knows how I can find a decent team that can start "soon" I'm open for suggestions, either here or in message.

Edited August 18, 2023 by puntloos

[Dillsue]

Sounds like you're unlucky or expectations maybe too high? Online sellers seem to have plenty of stock. It's summer holidays so every company has lots of people on holiday and may be struggling to fulfil existing orders. If youre trying to add to the workload then you might encounter some reluctance to take on the work. Good installers will likely be booked up for weeks or months in advance so you wanting them to start soon may be being overly optimistic. Maybe hold on til the autumn??

[JohnMo]

Went past an electric wholesale yesterday they had loads of panels.

 

I'm getting a battery, one week lead time and that's basically delivery time.

[puntloos]

3 hours ago, Dillsue said:

Sounds like you're unlucky or expectations maybe too high? Online sellers seem to have plenty of stock. It's summer holidays so every company has lots of people on holiday and may be struggling to fulfil existing orders. If youre trying to add to the workload then you might encounter some reluctance to take on the work. Good installers will likely be booked up for weeks or months in advance so you wanting them to start soon may be being overly optimistic. Maybe hold on til the autumn??

Perhaps so, it tends to be the whole 'value for money' thing I guess. People will make time if you pay them enough but as we all do we want a good job for 'barely reasonable' pay  

 

@JohnMo - am I understanding correctly you're going full DIY? How much are things costing you?

 

[JohnMo]

I did full DIY on the solar install, except the battery.

 

The PV is basic install with normal inverters. My second array I did a write up on this thread. All costs are included.

 

The battery system will be a Givenergy "all in one" system with full off grid switching in case of power cut. That isn't that cheap at £8200. Without installer permissions you cannot install and commission fully.

 

 

[puntloos]

One important thing I want from my inverter is that it will have enough 'free ports' to connect more panels to.. because.. I want to connect a car

Basically modern cars are able to let you use their battery as a 400V DC source, but you will need to plug it into your inverter (so an inverter with one socket for one panel array won't do). 

[Dillsue]

I think theres a handful of EVs that support V2G/V2H and I'm fairly sure they plug into a 2 way charger rather than a solar inverter. I think I read about a 2 way charger that also has solar inverter capability but not sure if it was available/approved for the UK.

 

If youre looking to use V2x then your best bet is probably install your inverter and cables near to where a future 2 way charger would go so you can hook up your solar when the time is right.

[puntloos]

21 minutes ago, Dillsue said:

I think theres a handful of EVs that support V2G/V2H and I'm fairly sure they plug into a 2 way charger rather than a solar inverter. I think I read about a 2 way charger that also has solar inverter capability but not sure if it was available/approved for the UK.

 

To my research, most V2H chargers do not have their own inverter built in (the dcbel one is an exception). Most of them just provide you with a beefy DC line that you can then "do something fun with". The main challenge really is actually finding someone willing to sell it to you. 

 

And the reason for that, to my mind, is that most of these 'experimental' chargers and charging trials are so hard to get into because they are run by power companies who want to buy your excess power. (V2G) and thereby fund it - I'm only a little interested in that. I want V2H. I'm too chicken to DIY it 

 

Yes, a charger with invertor makes some things easier but stull, you would only have a 240V AC line that you can wire an independent power socket to. If you want to integrate it into your house (and power eg your fridge) a lot of extra work is needed

21 minutes ago, Dillsue said:

If youre looking to use V2x then your best bet is probably install your inverter and cables near to where a future 2 way charger would go so you can hook up your solar when the time is right.

 

Done already 😃

Edited August 19, 2023 by puntloos

[Dillsue]

19 hours ago, puntloos said:

Done already 😃

?? I thought your post was about looking for installers??

[puntloos]

On 20/08/2023 at 13:55, Dillsue said:

?? I thought your post was about looking for installers??

 

For the PV, sure. But my standard sparky installed a DC cable from the charger to the inverter location. Nothing more.

[Dillsue]

So get your spark to install the cabling and a roofer to fit the panels.

[puntloos]

4 hours ago, Dillsue said:

So get your spark to install the cabling and a roofer to fit the panels.

I think that's a good idea, what I'm concerned about is that designing in-roof panels (e.g. GSE) is hard. 

Meaning, of course putting one 1x1 panel into a 10x10 roof is easy but if you want to fit as many as humanly possible how can you fit the most panels without running into trouble on-site etc.

 

Does anyone have experience with e.g. https://easy-pv.co.uk/ design vs reality? 

 

For example the panels fit within the limits, but the flashings overlap the edge, is that ok...?

 

Edited August 25, 2023 by puntloos

[Gus Potter]

On 18/08/2023 at 18:27, puntloos said:

Is it a bit of a 'wild west' area still,

Yes it is.

 

I have got into assessing roofs for PV in terms of making sure that they are still safe SE wise.. I ask questions..

 

Big learning curve and yes it is like the wild west. The problem I have is that once I explain what needs to be done to make the roof safe and water tight then a lot of the honest PV folk can't compete as it is a race to the bottom.

 

Some roofs are fine and can take the extra loading. Many old roofs are already over stressed when compared with modern design codes but sometimes you can still make things work with a bit of pragmatism.

 

My problem is that a lot of PV installers have no clue about what they are doing. Well a lot do and they don't give a jobby... it's a case of what can we get away with.

 

Never mind the SE side.. lots of PV installers will notch the tiles to get their brackets in. If you go back to Marley tiles who stand by their 50 year warranty on their tiles and ask them .. is it ok to cut notches in your tiles and reduce the lap.. they will tell you.. (expletive deleted!) no. If they could reduce the lap they would have done so decades ago as the market is so competetive.

 

If any PV supplier can't answer these basic questions that could compromise your house then why on earth would you part with several thousands of pounds to get a bit back on you leccy bill?

 

For me know knowing a bit more about the PV market.. under the bonnet... oh dear!

 

 Hopefully things will pick up in terms of transparency ect.

 

 

 

 

Edited August 25, 2023 by Gus Potter

[SteamyTea]

4 hours ago, Gus Potter said:

I have got into assessing roofs for PV in terms of making sure that they are still safe SE wise.. I ask questions..

Is that more MCS registered companies?

 

[Dillsue]

7 hours ago, Gus Potter said:

Never mind the SE side.. lots of PV installers will notch the tiles to get their brackets in. If you go back to Marley tiles who stand by their 50 year warranty on their tiles and ask them .. is it ok to cut notches in your tiles and reduce the lap.. they will tell you.. (expletive deleted!) no. If they could reduce the lap they would have done so decades ago as the market is so competetive.

Why would fitting roof hooks reduce the lap? The realtively few ones I've seen and done are notched to get the tile to sit neatly over the hook but theres no reduction in lap??

[SteamyTea]

21 minutes ago, Dillsue said:

Why would fitting roof hooks reduce the lap? The realtively few ones I've seen and done are notched to get the tile to sit neatly over the hook but theres no reduction in lap??

Not just the overlap that is important.  There is a lip and a rim that interlock, that is a secondary line of defence against tile movement in high winds, down here we have very high winds.

Grinding the lip away can cause the tile to crack unnoticed and cause problems in the future.

There really needs to be a replacement tile that has the notch moulded in.  Not sure if those are made.

 

[Dillsue]

I'm not aware that fitting roof hooks interferes with any of the interlocking at the sides of tiles- all thats needed is a notch at the bottom of the tile. Tiles are regularly cut for all sorts of roof features- dormers, veluxes, hips, valleys etc so I don't think there needs to be too much concern about notches for roof hooks.

 

Factory moulded notches would be awesome but getting the notch in the right place to match the hook would mean a selection of pre notched tiles which I guess is why they are site cut??

[Dillsue]

10 hours ago, puntloos said:

I think that's a good idea, what I'm concerned about is that designing in-roof panels (e.g. GSE) is hard. 

Meaning, of course putting one 1x1 panel into a 10x10 roof is easy but if you want to fit as many as humanly possible how can you fit the most panels without running into trouble on-site etc.

 

 

Do GSE do a design service?

[joth]

14 hours ago, puntloos said:

I think that's a good idea, what I'm concerned about is that designing in-roof panels (e.g. GSE) is hard. 

Meaning, of course putting one 1x1 panel into a 10x10 roof is easy but if you want to fit as many as humanly possible how can you fit the most panels without running into trouble on-site etc.

 

Does anyone have experience with e.g. https://easy-pv.co.uk/ design vs reality? 

 

For example the panels fit within the limits, but the flashings overlap the edge, is that ok...?

 

At least one MCS installer I know just turns up and sees how many they can fit on the day, having made a conservative estimate of kWp at quotation time.

Do any wholesalers allow 30 days for returns? Possibly overorder on panels and trays and return what doesn't fit.

Else sell them here. 

[puntloos]

1 hour ago, joth said:

At least one MCS installer I know just turns up and sees how many they can fit on the day, having made a conservative estimate of kWp at quotation time.

Do any wholesalers allow 30 days for returns? Possibly overorder on panels and trays and return what doesn't fit.

Else sell them here. 

Not a crazy idea by itself, although I do find that my roof is unlucky in that if I pick a 1684 x 1002mm 340W panel (5100W), I can fit 15, and if I use a more common 1762 x 1134mm I can only fit 11x 430W (4730W, and barely)

 

 

 

[puntloos]

I just realise there is one important extra option I failed to consider.

 

https://www.gb-sol.co.uk/products/pvslates/default.htm - solar slate tiles

 

A very important fact about these is that it sounds less fraught to get these right, since you can treat them as normal tiles, no weirdness around flashing, trays etc etc, so safer to DIY?

 

To my math, 

- the SE (main) roof is 48.1 m2

- GB-Sol says one 'unit' replaces four 500x250 slates, covering an area of 0.2sqm

- Therefore we'd need 240 units, at GBP59.50 each, 28W each

- Roof's power would be 6720W, materially higher than what I managed with panels (5100, maybe)

 

- The SW (side) roof I make about 33m2 -> 165 tiles -> 4620W

 

Total roof = 11340, price 24097 GBP.

11.3kW is much more than anyone else could fit on this except a company that I think made a mistake in their quote.

 

There's other solar tile companies out there too - one 

 

Rest of components (from midsummer)

 

Qty	Item	Unit	Line
1	SolaX X3 G4 12.0kW hybrid inverter	£2450.00	£2450.00
1	Emlite EMP1 Three Phase meter	£116.90	£116.90
1	Label sheet	£2.52	£2.52
2	AC isolator - Projoy 20A 4-pole	£8.40	£16.80
1	SolaX Triple 5.8kWh LFP Battery (Master Console)	£2702.00	£2702.00
1	SolaX Triple 5.8kWh LFP Battery (Slave Console)	£2226.00	£2226.00
22	Tigo Retrofit Frame Mounted Optimiser TS4-A-O	£53.20	£1170.40
4	Pair of MC4 connectors	£2.80	£11.20
1	50m reel of 4mm2 solar cable	£42.00	£42.00
Total (ex VAT and delivery)			£8737.82

This ends up at 32834 GBP ex delivery ex VAT ex install, so certainly pricy, but I care mainly about "per kwh installed" which is lower than  contract and artisan. Of course it does drive the total price up, but I could consider doing just the big (SE) roof, get 7KW, and use the remaining forticrete tiles on the SW roof.

 

Here's my pricing spreadsheet - I've anonimised the company names (Orange = estimate)

 

 

company (panel)	price ex ohp	install (if not inc)	# panels	power	total kwh	battery kwh	battery price/kwh	panel price/kwh	notes
A (Canadian)	£22,769.00		21	430	9.03	10	500	£1,967.77	- dubious if 21 can fit
B (JA Solar)	£24,514.00		16	370	5.92	10.64	608	£3,048.12	- pricy per kwh
Easy PV (Eurener)	£16,210.00	£2,000.00	26	340	8.84	11.6	500	£1,403.85	- small panels 1x1.6 - requires verification (minor flashing clash)
C (Solaredge)	£31,738.00		21	405	8.505	13.8	500	£2,920.40	- premium brand
GB-Sol Tiles	£32,834.00	£2,000.00	405	28	11.34	11.6	500	£2,560.32	- tile system
GB-Sol Tile (SE only	£23,017.00	£1,500.00	240	28	6.72	11.6	500	£2,785.27	- tile system

 

Of course aesthetics are important:

 

GSE Flashing

 

Solar Tiles

[JohnMo]

Have you lost the plot - at those costs you are talking 30+ years of electric costs, you may as well scrub the idea and just pay for the electric.

[puntloos]

6 minutes ago, JohnMo said:

Have you lost the plot - at those costs you are talking 30+ years of electric costs, you may as well scrub the idea and just pay for the electric.

 

Yes, these prices are pretty high, but especially the DIY option is about as low as things will go, are you saying solar is never worthwhile?

 

Also, I think I need some solar for passivhaus certification..

[JohnMo]

8 minutes ago, puntloos said:

saying solar is never worthwhile?

 

No not saying that - but you have to careful you are being ripped off.  I have solar (7kW) already and await a battery (13.6kWh) being installed. So I am all for Solar at the right cost.

 

 

[joth]

Last I looked at solar tiles (also GB sol) they cost 2x as much per m2 yet yield was 50% less per m2, so for a fixed roof size they give 1/4 of the kW/£ and half as much actual generation per year vs conventional panel. That alone is a none starter in my book.

 

Having used gb sol infinity I very much doubt the tiles are ideal for DIY install either, but a quick phone call to them would answer that 

 

I think there's very few situations they aesthetic is really justified for the inefficiency. From what I know there wouldn't be many places your roof will be very visible from. The example photos above of GSE are misleadingly ugly as it's at a very close camera angle that in practice no one will ever be viewing a 3rd story roof from