Final check before committing to solar PV quote

QrizB

Do you have a garage? You could arrange to buy the panels now and store them until your installation day comes around.

There are risks with this, of course, but I'm not expecting panel prices to drop significantly below 30p/W any time soon.

Screwdriva

boots_babe said:

I feel like I'm agonising over the panel choice, but we'll have them for 25 years so don't want to regret whatever we go with.

Forgive my American but your gut is clearly telling you something.. If it was my home, I would go for the better panels. LG typically come with a 25 year warranty on performance and defects. This is why I chose LG Bifacial panels in 2019 when they were £150 more per panel - haven't regretted it once. 

I would also insist on an inverter with better warranty. inverters are the primary "wear and tear" item on a PV system.  GiveEnergy's inverter is a better pick. SolarEdge is available with 25 year warranty.

Your battery choice is good.

 

rew81

boots_babe said:

Yes that's right, it's £100 more per panel if we go with the LG ones.

This installer was the cheapest by £1500 of the quotes we've had, so I'm  ow wondering if that's because he's somehow got the Trina 395 panels at a really good price?

I feel like I'm agonising over the panel choice, but we'll have them for 25 years so don't want to regret whatever we go with.

My first option would be Vertex S+, second LG and third Vertex S. 
Not sure which LG panel is that. Are you talking about LG410N2T-J5? That would be first choice without any doubt. 
I would not choose an inverter without a 10 years warranty. 
What I would add to my system is Tigo optimisers .Is nice to see the production for each panel and also would help to quickly identify if one of them is becomes faulty.
Probably now we are way over your allocated budget.

QrizB

I'd look at it the other way around. You'll be paying an 80% premium (£220/panel vs. £120/panel) for a benefit - a longer warranty - that's only going to have any value in 10+ years.

You could put that £2000 to work elsewhere for ten years (in your SIPP, say, or your SSISA) and then, if you do get problems, spend it to repanel in a decade or more.

Screwdriva

QrizB said:

I'd look at it the other way around. You'll be paying an 80% premium (£220/panel vs. £120/panel) for a benefit - a longer warranty - that's only going to have any value in 10+ years.

You could put that £2000 to work elsewhere for ten years (in your SIPP, say, or your SSISA) and then, if you do get problems, spend it to repanel in a decade or more.

Sure but what about the less obvious factors of inconvenience to repanel/ reinstall + the ethical argument of landfilling panels used only for a fraction of their potential duration + buying from a Chinese brand + dodgy warranty support etc. 

There are some who chose to look away from some of the above but that doesn't change the reality on the ground (or on the roof). 

Alnat1

Panels that are guaranteed for longer won't necessarily work for longer and may still need replacing, so reinstall/landfill point is not really valid. You would simply be paying a premium for a guarantee that you might never have to call upon. Panels tend to have few problems anyway, the bit of kit that goes, if any, is the inverter.

Nobody is going to notice whether you have a brand name on your roof and most panels tend to last the expected lifetime, wherever they were made.

boots_babe

QrizB said:

Do you have a garage? You could arrange to buy the panels now and store them until your installation day comes around.

There are risks with this, of course, but I'm not expecting panel prices to drop significantly below 30p/W any time soon.

We have some garages with plenty of space yes, but I wouldn't want to pre-purchase in case DNO the reject us. If they say our inverter must be  3.68kw max then there would be no point having so many panels.

boots_babe

I don't know how to do multiple quotes in one post, but will reply best I can below.

Screwdriva - thanks for your comments. My gut's not telling me one or the other, I just want to ensure I've considered all relevant factors properly before choosing. Our installer has Trina on his roof, his view was that they have a warranty and should have just as good longevity as the branded panels. That gave us food for thought.

Appreciate your thoughts re the inverter warranty, I hadn't really thought about that. I don't know if we could easily find an alternative which has a longer warranty, but will ask the installer.

rew81 - no the LG panels he's quoting are the 400w ones - LG400N3K-V6. Definitely don't need optimisers, our roof is south facing with no shading, so the only benefit would be individual panel monitoring which tbh just seems like a bit of added fun rather than anything worth having.

QrizB - interesting way of looking at things. Invested, that £2k would likely cover new panels if needed once the warranty expires. Hmmmm!

Alnat1 - being a true MSE, I don't generally care about brand names for most things, I go with what I think is best value, rather than brand name, or even the cost. I guess with this being a biggish investment, and having seen so many posts on here and other forums recommending branded over Chinese, it's made me question what's the most sensible option. Going back to the fact that our installer has chosen Trina over branded, coupled with your comment that they wouldn't offer a warranty period if not designed to last, perhaps I've been overly influenced by the brand advocates. I'm now leaning back towards the Trina.

rew81

True, optimisers are a must in some cases and just useful in other(panels analytics, quickly identify a faulty panel).
I did not added them and having mixed feelings- glad cause I did not pushed my roi ever further --  would have been nice to analyse each panel performance. 

Screwdriva

Alnat1 said:

Panels that are guaranteed for longer won't necessarily work for longer and may still need replacing, so reinstall/landfill point is not really valid. You would simply be paying a premium for a guarantee that you might never have to call upon. Panels tend to have few problems anyway, the bit of kit that goes, if any, is the inverter.

Nobody is going to notice whether you have a brand name on your roof and most panels tend to last the expected lifetime, wherever they were made.

Product warranties are offered by brands after rigorous field simulation testing by companies like Atlas/ Ametek. Warranty periods are offered on solar products only after these tests determine a safe threshold for the brands to offer their customers. To suggest that warranties are not related to product life/ performance over time, is simply incorrect.  

The jury is still out on the budget brand's product longevity. But it doesn't take much to "simulate" a warranty claim with a companies like Trina, Growatt etc. via their Customer Service departments to learn where you really stand, before making your purchase.