Domestic Solar PV Quotes 2022 - No PM requests - See Mod note post #1

DC999

https://www.boards.ie/discussion/comment/120396189#Comment_120396189

I'd agree with bullit. I got them on a flat roof that gets constant shading every day as the sun moves around the house (that the main roof above it doesn't get). I've seen some panels as low as 15w (as sun moves around the house and they are fully shaded) in the other end of the roof at 130w in the sun. It's a 25 year setup. Why not get optimisers for 50 quid a panel? So I've them on 5 of 16 panels and they rock.

Our installer said he'd recommend all panels get them as he has seen a permanent 20% output increase when they set them up on 2 like for like strings. He seemed genuine, wasn't trying to sell me optimisers. Of course none of us can say if that's true. But afaik the optimisers marketing material suggests a performance increase.

Ok, if it's a few panels on the string, it might not be worth it. But a main roof? Go for it, add them.

bullit_dodger

https://www.boards.ie/discussion/comment/120396216#Comment_120396216

I'd be somewhat skeptical about that 20%. Sure in some edge cases.....maybe. But no way is that a general rule. If we all could turn our 400w panels into 480 panels by adding an optimiser, we'd all be doing it :-) I know I would!

Still, while I know what your saying about the bypass diode radiofoot, it's not something that's applicable to all makes/models of panels. The issue is that if you don't install them day 1, and then you find out that your production massively suffers......it's a ball-ache to get the supplier back out again and up onto your roof to take the panels off and hook in an optimizer. It's like a 60 second job if doing it on the same day, but solving it after the fact is a chore.

Have a chat with him/her. Most installers are honest, hard working folks who'll generally steer you right with advice. Sure, there's a few muppets out there, but unless you've reason to doubt them.....most of them will give you the right story.

radiofoot

https://www.boards.ie/discussion/comment/120397346#Comment_120397346

Thanks, I will do. I actually really like the guy I am dealing with and he's definitely a trustworthy guy.

HotSwap

https://www.boards.ie/discussion/comment/120398967#Comment_120398967

I would not take any advice from someone that is trying to sell you something without independently validating it.

Watch this video; I believe they are not needed any more. This guy did some extensive testing.

https://youtu.be/E9NVLB_OYSU

In fact you will loose 1-2 % power from all panels as the optimiser needs power to run. They are also the most commonly replaced part in solar PV systems; and while they may be under warranty; which will get you a replacment 50 euro part (big deal) the warrantee doesn't cover the labour to get on the roof and replace it.

what panels are they proposing? I’ll have a look at the data sheet for ya and let ya know how they will behave in shading conditions.

HotSwap

https://www.boards.ie/discussion/comment/120395432#Comment_120395432

This isn’t true anymore. A shaded (or partially shaded) panel will be bypassed and not impact the others; combined with more advanced MPPT algorithms (like in huaweis and solar edges) that can detect the best global values to run a string at; really kill the need to run any optimisers at all.

the main reason to run them anymore is:

1.) Access to tons of panel level data. Which is cool. But wont power your kettle :)

2.) safety; when the inverter is off each optimiser will only output 1v; so you can be sure you don’t have live DC cables of your doing maintenance. Some countries require panel level optimisers for this reason (not Ireland).

3.) some manufacturers allow you to connect a higher KWp of panels on a single string when you have optimisers installed. You might normally be allowed to do 150% DV oversized; but with optimisers you can go up to 200%.

bullit_dodger

https://www.boards.ie/discussion/comment/120399438#Comment_120399438

I think that's perhaps overtly negative. There are many a good installers out there who'll steer the customer right or at least try to steer them right. Sure - like any industry there are snakeoil huskster salemen out there too, but in this case we're talking about two (maybe 4) €50/unit devices. Allowing for 30% profit margin we're talking about an additional profit to the installer of what €80? hardly seems worth the effort on their part.

As for that guys video, its interesting as I was aware of the bypass diodes.....and yet, 2 brand new (Qcell) panels purchased myself and installed last August I decided to test the effect of shading myself on the panels measuring the voltages/amps and saw that the panel on the left was producing 350w and the panel on the right......28w. (all due to that tiny little shading on that bottom right of the right panel)

https://www.dropbox.com/s/3pxbhk35rwkriyg/2022-08-10%2012.02.36.jpg?dl=0

10 mins later (when the shadow disappeared) both panels doing 350w.

So....dunno. That Swiss guy seems to know what he's talking about, and yet, my own eyes have seen the drop off in perf. Maybe the Qcells don't have those diodes. Main thing is that it's not a "given" that you can ignore optimizers - and it's ok to have conflicting opinions on that.

HotSwap

https://www.boards.ie/discussion/comment/120399580#Comment_120399580

if you were measuring the wattage in your inverter that’s not really a useful measurement.

you might have a budget inverter that can’t do global MPPT scanning; you would also need to give longer than 10 mins for the inverter to do a full scan (if it is even going to do one).

you need to look at the raw voltage and amps coming out of the panel to know what is really going on. And compare how that is impacting the overall strong voltage and amps.

radiofoot

https://www.boards.ie/discussion/comment/120399438#Comment_120399438

The panels are Jinko 410W P Type Panel. I'd be interested in what the data sheet says, thanks.

HotSwap

What’s the model of them panels; interested to look at the spec sheet / manufacturing process they used To see if that has any clues also.

HotSwap

https://www.boards.ie/discussion/comment/120399747#Comment_120399747

Cool. I’ll dig into it this evening and see if I can find anything. I have the jinko 415w n type panels on my setup. But I have a ground mount and 0 shade; so it will be interesting to see.

bullit_dodger

https://www.boards.ie/discussion/comment/120399741#Comment_120399741

Nope, I was measuring with a multi-meter, and each panel was hooked up to a micro-inverter (with it's own MPTT), so I had additional telemetry from that also. It should have been a good test. With the bypass diodes (if working/present) I'd expect to have lost maybe 30% or so as it was only that small area covered down at the bottom, but no. I'd about 90% loss in production in the panel. Shadow went and full production restored.

To be clear here, I'm not saying you/that Swiss guy is wrong - what I'm saying is that I didn't see that in my own testing - but potentially explainable by lack of diodes in the panels I have. The key takeaway here though (as this is the "quotes thread" and much of this is beyond your average layman) is that I'm not sure that it's fair to say that optimizers can simply be ignored. There's a time/place for them and if your supplier is decent enough, they should be able to advise honestly.

smax71

https://www.boards.ie/discussion/comment/120395832#Comment_120395832

I'm sorry to bump this but I'd appreciate anyones view on whether installers are starting to advise not to get a 6kw inverter and instead opt for what seems to be the new default 5.5kw option? I'm trying to get agreement on a quote for a 6kw inverter in order to install 8kwp of panels and I'm a bit surprised to be advised not to specify a 6kw quote as these may be obsolete and possibly not available post 31 May

con747

https://www.boards.ie/discussion/comment/120400540#Comment_120400540

As far as I would be concerned once the NC6 is submitted before the deadline 31st May there is no reason an installer should be dissuading you from that inverter. If a warranty issue arises I can't see any reason why it would not be able to be replaced. If you want it, push for it. Just make sure you get confirmation from ESBN they received the NC6.

graememk

Warranties are usually covered by the manufacturer, eg, inverter dies, and you go to solis directly not the wholesaler.

con747

https://www.boards.ie/discussion/comment/120401367#Comment_120401367

The seller is the one who must rectify any issues with faulty goods under your consumers rights and I imagine that is why installers are reluctant to install the 6kW inverters before the deadline so they don't need to deal with any possible warranty issues in the future. The bottom line is they have no real reason not to keep fitting them as long as ESBN allow them to IMO.

radiofoot

https://www.boards.ie/discussion/comment/120399769#Comment_120399769

@bullit_dodger although one panel was badly affected by shade, did your test demonstrate that the rest of the array would not be affected? I'm wondering if I should just add an extra panel instead of the optimisers. The cost wouldn't be too different and it might be a good solution with less risk of maintenance down the road?

graememk

My understanding is diffuse shadows, ie leaves from a tree benefits from optimisers, but a hard shadow the bypass kick in and bypass that panel.

I'd be leaning towards extra panel vs an optimiser.

bullit_dodger

https://www.boards.ie/discussion/comment/120402871#Comment_120402871

Well for me I had a 1:1 panel to micro-inverter, so it's not a comparable test. What it showed in my case that that small (5% or so shading) resulted in a 90% loss in production on that panel. With by-pass diodes and the way that the panel is supposed to be split into sections, you'd have expected that there'd only be a 25-30% loss. That didn't turn out to be the case....at least for me. I don't have enough data to speculate beyond that. While new, maybe my panels don't have it. Maybe I messed up with my readings. I'm not infallible :-)

If it was me, it's 2 (maybe 4) optimizers. I'd bang them on the panels next to the chimney. The arguments of "Ohh but if they fail, you'll have to get a guy out onto the roof" is sort of redundant/pointless. They fail "passively" - as in if they do fail, then it's the same as if you had no optimizer. They are designed that way, so there's no "risk" as such in installing them barring the initial cost - which at €50/unit, it's small compared to the overall installation cost of €10K (or more).

They operate at <1% of your production and to take solaredge as an example the warranties are 25 years. SolarEdge - Solar Inverters and PV Optimizers (solaris-shop.com) while the string inverters are usually warranted for 10-12 years. i.e. there's more likely a chance that your string inverter will fail before an optimizer, the reason being is that they operate at 40v as opposed to the higher voltages (400-500V) that a string inverter has to deal with

Again, have a chat with your supplier/installer. No harm in solicitating advise from all corners and then you can make a more informed decision.

Aside: If you have a choice about adding extra panels, then you should add the extra panels also :-)

zoom_cool

Best Quote I got so far is

10 x 400w Puma Recom Panels

1 x 6Kw Solis Hybrid Inverter

All fittings

€6100 incl SEAI Grant

I have decide to go ahead.

smax71

https://www.boards.ie/discussion/comment/120405007#Comment_120405007

I see that quote incorporates 6kw inverter. As a matter of interest will the system be installed before 31 May?

zoom_cool

https://www.boards.ie/discussion/comment/120405917#Comment_120405917

Yes it will.

smax71

https://www.boards.ie/discussion/comment/120400574#Comment_120400574

Agree and that's why I'm a little surprised with the position being taken.

Citizenpain

10 x 420 Watt Trina Solar Panels

4.200 kW Solax Inverter

5.8 kWh Solax Battery

S/E & S/W setup

10,500 after Grant

alfa_aficionado

What do people think of installers issuing quotes without site visits, based on photos etc?

con747

https://www.boards.ie/discussion/comment/120409266#Comment_120409266

Standard procedure really with most installers, google earth gives them a rough guide of your roof for panels.

con747

https://www.boards.ie/discussion/comment/120408988#Comment_120408988

Input it in to this calculator http://davidhunt.ie/solar/ it's expensive.

alfa_aficionado

https://www.boards.ie/discussion/comment/120409276#Comment_120409276

Fair enough...thanks.

Latro

20 panels - all installed on 1 side of south facing roof, 6kw hybrid inverter, no batteries.

One quote was 18,000, the other 16,500, vat included, grant not included. I will defenetly pass on these.

If any installers have more reasonable offer, please PM me. I'd like the job done asap if possible. Co. Kilkenny.

DC999

https://www.boards.ie/discussion/comment/120410912#Comment_120410912

Hey, no PM'ing please. This one lists some installers that people here have used: Solar PV Boards Members Installer Information — boards.ie - Now Ye're Talkin'

When getting quotes, check the size of the panels in watts. Then you can compares apples and apples. They can be different sizes. Take the overall capacity of solar (number of panels x watt per panel) and divide that into the vat inclusive price post the grant being removed. Then you’ll see the price per 1kWP to compare quotes. 

The panels can generally be oversized relative to the inverter. But the installer will need to check the inverter can handle it.

It’s deffo worth finding decent quotes. I’ve solar since summer last year and would never live in a gaff again without it.

If you’re using a single roof, that’s much faster for them to install. So you can expect the cost to reflect that – less labour for roofers and sparks to join cable routes back to the inverter. Ours was across 4 small roofs and took them heaps of days onsite.  

Latro

https://www.boards.ie/discussion/comment/120410987#Comment_120410987

Hi, 400-450w is a standard these days. They are all about 190-220 euro per panel.