Domestic solar PV quotes 2018

conor_mc wrote: »

Set up a demo account on helioscope and you can play with the panel types/locations, and then run simulations to see how much each setup will generate per year.

Looks like 12 bisol 300 modules would fit maybe

https://www.dropbox.com/s/l0ifnhnbu3uctta/Screenshot%202018-11-13%2013.06.41.png?dl=0

https://www.dropbox.com/s/qomm1ghxah380ba/Screenshot%202018-11-13%2013.08.33.png?dl=0

GaryCocs wrote: »

I got this message from one installer.

"because the seai in their wisdom will not allow a panels edge within 50 cm of the edge of any of the roofs edges this makes the area work out to be instead of 7.2 it will be 6.2 and the 2.1 meters makes it 1.1 meters therefore we cannot fit a panel as the grant will not be issued"

I’d heard that before, and seen it mentioned here too. I think it’s to help prevent strong winds lifting the panels.

unkel wrote: »

Is an in roof system exempt from the 500mm rule?

I've no idea, I was only speaking from a practical perspective as regards getting his panels installed if he goes ahead without the grant.

I've only skimmed the headline figures for the grant - 800/kW to 2kW, 1k for battery system, additional 800/kW for 2kW up to 4kW with battery.

The 500mm rule is pretty sound in my experience. It's difficult / impossible to lift tiles near the ridge to fix roof hooks anyway without removing ridge tiles and having to reinstate them which is a lot of work.
The ridge and eaves are also the areas most prone to leaks and thus most likely to require access for maintenance so it's sensible to leave them free of panels.
The in roof systems are well suited to fitting right to the eaves however and are less likely to leak than slates or tiles if properly fitted.

The gap also maintains some access for getting onto the roof and around the panels. This is useful for maintenance and I believe fire brigades mandate it in some regions also for this reason.

GaryCocs wrote: »

Do slates need to be lifted on a slate roof too? I see some information in relation to solar limpets.

They do as far as I'm aware. I've never installed solar on a slate roof.
I hate the sight of slates having had the misfortune of ripping and replacing a few in the past. My all time least favourite roofing material - apart from shingles but I wouldn't consider those roofing material!

€100 for a 300W panel. Plus shipping from continental Europe and VAT? Not much cheaper than you can get the panels here then?

air wrote: »

Just had a look at those solar limpets and to me they look all kinds of awful.

They're totally reliant on the underlying roof members - do they fix to the slate battens or the rafters? It looks like it's the battens but it's not 100% clear from the installation video.
No possible way to inspect the condition of the timber you're fixing into, confirm it's dimensions or confirm that the fixing is centred in the member before or after you fix.
The structural certification they provide is based on a laboratory test on a perfectly installed fixing on a piece of timber that is far larger than a typical slate batten.
Waterproofing of your roof becomes entirely dependent on some outdoor sealant.

All my concerns may be totally unfounded but I wouldn't want a product without an established successful installation history on my roof.

Ya will have to talk to a few installers. I'm in an ok position of having an open roof on the other side, i.e. I can see the rafters underneath on both lean to and garage.

GaryCocs wrote: »

Ya will have to talk to a few installers. I'm in an ok position of having an open roof on the other side, i.e. I can see the rafters underneath on both lean to and garage.

Looking at the structural analysis document properly they have de-rated the pull out strength to allow for poorly centred fixings in the rafters, so they're definitely fixed to the rafters and my concern about missed fixings was valid.
The next issue this raises is compression of the slate towards the rafter where the fixing is not on a batten.

wexfordman2 wrote: »

So the concern is not over the product itself, but whether or not it is properly installed ?

I'd have concerns (structural) about how likely it is to be properly installed, even with the most skilled and attentive installer.
That aside I'd have further concerns (leaks/longevity) even if perfectly installed.

Roofing is not an area of expertise of mine.
I'm only going on my experience of having repaired / replaced slates a few times and having installed PV on tiled and steel roofs in the past.

That being said, even being correctly installed there's an appreciable risk that an excessive number of fixings will not be centred in the rafters. If this occurs, the pull out strength of the installation is compromised. Worst case scenarion the entire installation could fly off the roof in a storm.
It should be noted that the structural analysis provided by the manufacturer specifically acknowledges the risk of missed fixings. It's only a matter of time and odds before someone misses too many and runs into trouble.

The hole through the slate is at risk of causing the slate to split due to stresses imposed on the bolt by wind loads. Any resultant movement is likely to be exacerbated by the first point. .
A lesser risk is perishing or improper use of the sealant admitting water through the bolt hole.
Finally, depending on the particulars of the roof, there's potential to put stress on the slate due to the fact it's fixed rigidly at two points.
There is also potential for splitting due to thermal cycling of the slate depending on the clearance around the bolt hole and how tightly both bolts are fixed.
Any one of these four mechanisms has potential to cause leaks.


Having said all this an installation with perfectly centred fixings, torqued precisely and sealed perfectly may well be fine for a prolonged time. This is just my somewhat educated opinion on them.

As a final point, I wouldn't put any value on SEAI approval. They have approved some very dubious companies and products in the past in my opinion.

It's not a huge concern as the current is typically under 10A per string.
The percentage of total energy production the losses represent decreases the more panels you have in series also.

Yes, that and the fact it doesn't look great. You'll also use a few more hooks and clamps than a continuous row.

That would be the extra cost, a frame with ground anchor points, also fence it off.

GaryCocs wrote: »

Sooo putting them in the garden, is there an additional cost? Can you get some box iron fabricated for it etc?

You wouldn't need planning as it's a temporary structure. Some ground mount systems just require big concrete feet to hold them down, no digging and pouring concrete. The angle can be set to the optimum, unlike a roof mount, and sun tracking is also a possibility.