Solar Quote

ed110220

bergy2 wrote: »

Hi


Got 3 companies visiting -now know the roof is SE, other NW


Shading is basically a chimney and rising edges - that's it so wonder if the optimisers are worth it at all?


Had a quote with 8 LG panels 300W £4750, Samil Inverter


Andy

Yeah, still too much, I was quoted practically that for 12x 300W LG panels. If you are only going to have eight panels you really want to squeeze as much wattage out with the highest efficiency panels such as BenQ 330W or the Panasonic HIT range. The Panasonics are 240 -250W but smaller so you may be able to fit more on, depending on the roof dimensions.

As for shading I think when and for how long is going to be more important than how much. Even a small amount of shading can dramatically cut generation. On the other hand if the shading only happens say late in the day, especially in winter it may not be important as there isn't much generation to lose then.

Ed

Martyn1981

bergy2 wrote: »

Oh and do Solar Edge Power Optimisers have to be used with a solar edge inverter? Or can they be used with say a Sunny Boy?

Hiya bergy. You can use PO's with non SolarEdge inverters, but you'll probably have to buy an interface device (about £200). But ..... the SolarEdge inverter is relatively 'dumb' as it doesn't have to do so much work, so are cheaper than SMA's (Sunny Boys). Also the SE inverter is highly efficient, into the 98% range, and comes with a 12yr warranty. So, it's a better match for the PO's, costs less, is more efficient, and has a very long standard warranty - what's there not to like?

Rooves - Here we go ... (somebody, somewhere on MSE has just won the 'when will Mart mention a North roof' pool ) ... since your south east roof is relatively small, then your options are to:

pay for very expensive higher efficiency panels, not a bad idea, perhaps 8 x 330Wp giving you 2.64kWp, or

use the NW roof too. Slap 2kWp of normal panels on each, this may not be that much more than the high efficiency panels, but will probably be about 50% more than just fitting 2kWp of regulars on the SE roof only.

Generation wise, looking at central Bristol (randomly) on PVGIS I got approx generation figures of:

South (azimuth 0) 970kWh per kWp
SE (-45) 914kWh/kWp
NW (+135) 602kWh/kWp

Jumping ahead (and just ask if this doesn't make sense) but the SE only system with SolarEdge kit to mitigate the chimney shading, perhaps £3.5k, and the twin roof system (again with SolarEdge) costing perhaps £5.5k.

SE 2x914 = 1,828kWh. £3,500/1,828 = £1.91 per kWh.
SE 2x914 + NW 2x602 = 3,032kWh. £5,500/3,032 = £1.81 per kWh.

So, rather unscientifically, the twin system works out at a similar cost, relative to size and generation.

[Edit. For comparison, let's assume that a system using 8 330Wp panels costs about £4.5k. So SE 2.64kWp x 914 = 2,413kWh. £4,500/2,413 = £1.86 per kWh.]

I know it sounds counter intuitive, but a lot of PV costs are fixed (scaffolding, inverter, paperwork, internal wiring etc) so going bigger doesn't increase costs proportionately. A NW roof will never be ideal, but having some decent generation in the evenings Apr to Sept is nice and helps when it comes to cooking tea.

Mart.

jimjames

tunnel wrote: »

Ok, i have to ask, why the solaredge? Do you have shading? Any shading? A little bit of shading?

As for the price....forget it...too expensive

8 x benQ 285W panels are a little over £1200 RETAIL(sunedison equiv)
1 x inverter(single string) £500
1 x scaffold £500
Racking/cables/switches etc etc £500
Price £2700 + fitting

There are also higher rated panels(benQ 330W) to make the most of a small roof

Again...above prices are retail NOT trade prices of which the installers are privy too

That's really useful to know.

I'm looking at getting more panels added to my roof. Having done the calcs it looks like it will need to be a separate installation to avoid reducing income from my existing setup.

As we got ours 4 years ago I'm a bit out of touch with current prices. We won't need scaffold as that will already be there from putting roof on so looks like a very good price is possible!

Any tips on companies to contact in SE England?

bergy2

Just visiting my brother who has 21 panels and a 6000 solaredge inverter and POs so can see the quality. The quote was a single string SE Inverter so will sound out a dual and looks at quotes for both rooves.
Do folks haggle down showing the retail costs as a method??

tunnel

bergy2 wrote: »

Do folks haggle down showing the retail costs as a method??

It certainly can't hurt to try, if the installers "think" you know what you're talking about there's less chance that they'll try to rip you off and it does seem to have helped quite a few posters who have gone before you on these forums.....what do you have to lose?

Martyn1981

bergy2 wrote: »

Just visiting my brother who has 21 panels and a 6000 solaredge inverter and POs so can see the quality. The quote was a single string SE Inverter so will sound out a dual and looks at quotes for both rooves.
Do folks haggle down showing the retail costs as a method??

Morning. Not sure if SE means South East or SolarEdge, but a SolarEdge system will be single string, regardless of how many different orientations, pitches and even panel types there are.

I forgot to mention in my last post, but I'm suggesting SolarEdge due to the chimney, since it sounds like it will have a small, but significant effect on the South East roof, and will therefore have a bigger hit on the North West roof (being more southy(?) to it).

My WNW roof (with SolarEdge) has shading from a chimney (to the south) and a small bay roof (also to the south) but so far has performed roughly on target with PVGIS projections for an un-shaded roof - which I didn't expect.

Mart.

bergy2

Ah mixing my strings and DC inputs up - sorry - meant 2 inputs


Great help guys - will update next Wednesday


Thanks


Andy

bergy2

Quote 1 in from the company with a lot of good reviews
They offer the longest workmanship warranty of 10 years


15 x Phono Solar Onyx SE - Smart Module (265Wp) modules


1 x SolarEdge SE-3500


This is on 3 rooves - 8 South Facing, 3 West facing and 4 North - maximises sunlight 3.98KW rating 3.233 estimated yield


Involves 2 scaffolds so £6600

bergy2

Quote 2


11 LG 305W Mono Neons
11 3 P350 SE Optimisers
SE 3500 Inverter


Includes a full breakdown of costs which impressed me


Now I did the maths on the panels, POs and Inv and can take £250 off if I ordered and had delivered but at 5% VAT (I know I can't btw)


What actually is the markdown with wholesale prices? Is it just the VAT element or more? How I ask for a reduction is based on this really?

bergy2

Ok made a decision - thanks for the advice earlier


Getting 10 panels on the South facing roof


10 LG 305 Xeon
SE 3000 Inverter
P350 Optimisers
EPC included


About 2750KwH


Knocked them down £150 to £5400 - best of the 3 quotes