Assess My 4kwp Install Quotes Please

ventureuk

Northern England, 37 degree slate roof facing SSW, fractional shading from chimney, due to Velux lends itself to 3x5 configuraton and one above for 250w panels or 3x5 265w panels. All quotes inc vat, fitting, scaffold, warranties, etc and are from larger solar companies with a good reputation. All give very similar FiT figures.

1. 16 JASolar 250w mono panels, Mastervolt, Fronius or SMA inverter (my choice), tiles removed, cut, bolted, leaded and replaced, grey panels £7800, black panels £8000. Configuration for this put the panels all over the place and the price seemed a bit steep, own fitters and scaffold, salesman came and was salesman like (read double glazing).

2. 16 Sunrise 250w mono black panels, Aurora inverter, bolted through the tile, 3x5+1 configuration, £7088. Never heard of the panels but they have a 12yr warranty, don't really like the bolt through tile install, price seems ok, own fitters and scaffold, guy who surveyed will be lead fitter.

3. 15 Yingli Panda 265w black frame black panels, 5x3 portrait configuration, or 16 Suntech 250w in a 5x3+1, SolarEdge inverter with 15 micro inverters, one on each panel which treats the install as individual panels rather than taking an average across all the panels. Inverter linked to internet for comprehensive monitoring and individual panel diagnostics. Tiles removed, cut, bolted, leaded and replaced. Very techy electrical engineer did the survey, huge knowledge and gave Google sketchup plan.
£7500 for Suntech
£7800 for Yingli

I really like the SolarEdge micro inverters, very sensible it seems, lets you mix and match panels if one is failing/broken and actually lets you identify the failing one for a warranty claim (difficult with a single inverter).

I'm swung to system 3 and would be grateful for the opinions of the solar experts on here.

Thanks

Martyn1981

ventureuk wrote: »

I'm swung to system 3 and would be grateful for the opinions of the solar experts on here.

Thanks

Can I sneak in through the back door as a nosey but passionate amateur?

Is it ok to ignore option 1, since it's not cheapest, you're unsure of both panels and sales? Go with your gut.

So next question, how will the layout look, whilst not crucial, probably worth considering, since you have 2 options? 3 by 5 sounds much neater, unless the 'stray' panel somehow 'balances' the Velux?

Coincidentally, just been reading up this afternoon on SolarEdge, sounds very interesting, especially if pricing is similar.

If the above issues aren't actually important, then funnily enough I'm still drawn to the black pandas, as YingLi are so well known, and they should look quite nice. Other than that, you seem to have 3 reasonable offers, I suppose you could go further and try to see some work examples, references, internet research the companies etc?

Is it fair to say, that you may have already made your mind up? Your post seems quite enthusiastic about a particular system.

Best of luck.

Edit: Have you been onto PVGIS climate to check the numbers? Are you happy with them?

Mart.

ventureuk

Wow, thanks for the PVGIS link Martin.

The calcs based on all factors give an 18.7% system loss.

A yearly production average of 3430 kwh and a yearly irradiation level of 1060 kWh/m2.

The value provided by the compnies was 3286 so I should do better than the predictions......I think.

I imagine if I chose system 3 the inverter would reduce system loss slightly by dealing with each panels production independently rather than as an average.

The 16th panel would balance the layout on the 5x3 above the 3rd central top panel and between the Velux, so it would look ok and save £300 at £7500.

Have a watch of this video, to my amateur eye it seems like the Solar Edge is a common sense approach to electronically managing the panels hence I favour this one.

http://www.youtube.com/watch?v=lsa9rHpDVmQ&feature=plcp

jamesingram

One thing to consider with mirco inverters, 15 more thing to go wrong
I believe the true value of mirco inverters is where there's a shading issue , if there isn't it might be over kill .
all seem keen prices , bolt through works , but cant be as good as a flashed in racket done well , as long as it is done well.
cheers

ventureuk

jamesingram wrote: »

One thing to consider with mirco inverters, 15 more thing to go wrong
I believe the true value of mirco inverters is where there's a shading issue , if there isn't it might be over kill .
all seem keen prices , bolt through works , but cant be as good as a flashed in racket done well , as long as it is done well.
cheers

That's very true, but the micro optimizers have a 25yr warranty with the main inverter having a 12 yr warranty, the risk is greater with more components as you say.

It sounds like I'm talking myself into system 3.

Martyn1981

ventureuk wrote: »

Wow, thanks for the PVGIS link Martin.

The calcs based on all factors give an 18.7% system loss.

A yearly production average of 3430 kwh and a yearly irradiation level of 1060 kWh/m2.

The value provided by the compnies was 3286 so I should do better than the predictions......I think.

Have a watch of this video, to my amateur eye it seems like the Solar Edge is a common sense approach to electronically managing the panels hence I favour this one.

http://www.youtube.com/watch?v=lsa9rHpDVmQ&feature=plcp

I've found the climate figures to be very accurate, and monthly differences can usually be explained away after checking the sunshine anomaly maps, or after accounting for some extra shading (which I get Nov to Feb on my smaller system, perhaps 10%). You mentioned shading from a chimney. As my house is the north half of a semi facing E/W I get chimney shading around 3pm. Strangely, numbers don't appear to be affected, but that might mean I've got the losses set a little high on PVGIS. Either way, there has to be a loss somewhere.

Thanks for that clip, would have saved me an hour reading through tech sheets and brochures. Certainly sounds ideal for a little idea I have. Let's just hope they are being honest. Then again, I'm sure we'd have had a few people letting us know on these threads if the claims were wildly exaggerated.

If you go for it, when is decision time, and when can they start? Actually that's a good point, have you checked for work slots? I had two very similar quotes last year, but one could start 8/8 the other around early Sept. So quite an expensive delay in FITs terms - unless you wait 25 years for the extra month at the end!

Mart.

ventureuk

Thanks solarsteve that's good to know.

Which panels do you use ? Would you go for 15 265w or 16 250w ?

ventureuk

Thanks solarsteve, sent you a pm.

Martyn1981

Solarsteve wrote: »

Hi,
we now have 77 installations using the solaredge inverter and have two more being installed next week!
For unusual installations with shading, panels on three roof faces and uneven numbers of panels (6,10 or 4,12 etc) then we really like to recommend the solar edge system.

Cheers
steve

Hiya Steve and thanks for those posts, slowly getting my head around this. I'm playing with the idea of a small install, that at 6 panels is too expensive, but by 8 panels is getting 'ok'. But those 2 extra panels would be sited to the north of a bay roof sticking out of a west roof. they'd be approx 1000mm from the bay roof, but I'd expect the shadow as the sun moves from the south to the west, to go right across them for a while. Hence my interest in the SolarEdge approach.

Can I be cheeky (I'm always asking that!), not asking for any actual full system costs, but are you able to say if there is much/any total cost difference? For the sake of argument lets say 2 to 2.2kWp on a SB2000HF v's a SolarEdge SE2200.

As I say, not trying to get you into trouble (business wise) on this forum, only want to know proportionate difference. Just trying to get a fuller picture of options before looking at this again.

Edit: Even cheekier, are they easy enough to install / more work and hassle? M.

Thanks.

Mart.

Watt-NRG

ventureuk,

Installation prices are fair and good to see quality products quoted.

Micro Inverters are very good and do offer a very efficient solar system. The only thing I would say it that the cost to replace these will be expensive. The life span of your solar system will be 25 years plus and you can expect inverter failure and the need for replacement during this period. Replacement of Micro Inverters will be expensive as you will have the added cost of removing the solar panels to access the inverters, this will require the cost of scaffold etc. Also bear in mind that not every inverter will fail at the same time, so you will require multiple visits in order to replace them. A single inverter can be replaced easy, with easy access and in one visit. Also please bear in mind that technology in the inverter area will have improved drastically when the time comes to replace it, with improved efficiency from a cheaper product.

Micro Inverters are a very powerful tool for properties with shading issues but the above is worth definitely worth considering before taking the jump with Micro Inverters.

Hope my input is of use, Sam.