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

Actually you don't need optimizers on an East/West split - as odd as that sounds. I was always of the impression you needed optimizers if the aspects were different, but I was wrong. (albeit there are caveats) You can connect the panels on each roof in series as normal, and then you connect the array of East & West in parallel back to the 1x input on the inverter. Losses are expected to be in the low single digits.

The caveats are that you have to have the same number of panels on east as you do on west, and they have to the same type. The reason for that is your matching the internal resistance of the east with the west.

For a more technical explanation of why this works....

Technical_Articel_East_West_Fachartikel_InterPV_EN (energymatters.com.au)

(skip down to sections 4&5 if your not interested in the technical bits)

It came up before and someone mentioned "I've different aspects and no optimizers and it works fine" - but at the time I didn't know the reason why. It struck me as strange back then , but yeah it'll work ok. It also might open up options for people who can quote for three roofs :-)

Might perhaps be better in the solar "tip and troubleshooting topic" , but I stand by that no such thing as a dumb question. Jasus you'll never learn anything unless you ask questions! We need to foster that more....

So the quick answer is, "yes" you can charge your EV from your house battery. The longer answer is that it's not ideal. The problem is that charging and discharging a battery involves "losses". So if you put 10Kwhr into a battery expect to only get 8.5-9.0Kwhr of that energy back from the battery. The reason is complicated involving ion exchanges and chemistry. Ideally you want avoid

Solar panel -> house battery -> car battery

as your going through 2x "battery chargings" in the chain and you'd be increasing your losses. Better if you can just

Solar Panel -> Car battery.

But of course if your car is at the office, that's not always possible.

I've read through that paper and I'm still not 100% convinced even if I can't pick holes in the methodology. My own experience of watching the performance of panels even slightly shaded dragging the whole string down makes me very nervous. Problem is, that if someone tries it and it doesn't work for them, they have either spent a bunch of money on something that doesn't work or they have to spend a bunch more to get it working.

But hey, if anyone wants to try it and let us know how they get on I'd be glad of the practical experience information :D

Everyone's a skeptic - LOL! I was somewhat dubious myself, but here's a solar installers opinion.

Solar Panel Design : North-East-West | MC Electrical

He's in Australia, so his "north" is our "south". The math makes sense - that's what convinced me. Math never lies. Might be better we continue this conversation over in ?

Solar PV Hints, Tips & Troubleshooting - Page 72 — boards.ie - Now Ye're Talkin'

How much have people been paying as a deposit for a system that is Grant approved? I've been quoted a deposit that is nearly 30% which seems excessive

I didn't pay a deposit, no way would I give anyone money without guarantee I can get it back if they go tits up... don't pay the ferryman :)

Thanks for this insight. I currently have a GSHP which looks after all my hot water automatically on night rate in the event that solar thermal are not sufficient. However, your response has given me potentially another option for an Eddi - it could be potentially be placed on the HP buffer tank rather than then hot water cylinder (I have 2 separate tanks both with emergency back up immersions). I will have to go back over my usage data and look again at my calculations......

Probably about €1500 more than you should pay - and that's being a little generous.

I'd probably advise a small battery to improve your overall efficiency. Ideally 5kwhr, but even a 2.5Kwhr one would help a lot.

Even if the price was OK (which it isn't) I wouldn't deal with anyone pulling that high pressure sales tactic crap.

Tell them to sod off.

Thanks for the responses,

The high pressure sale was well noted and a black mark in my book.

Hoping to add a battery at a later point depending on our usage profile, both work from home permanently so power usage is high during the day but often out and about for the evening and in bed early so generally low.

Waiting for a quote for solar as a service but they are saying they only make the trip to Cork once enough demand has built up.

That's a poor quote. Send that price gouger packing!

The discount by Friday thing as well. A red flag.

Offer him 5k and no more. Even then it's probably a stretch.

Scandalous quote, its over by about 2.5k in my opinion, there are better prices out there.Unfortunately it now seems quite a few companies are charging exorbitant prices, the grant is now factored into quotes as some kind of free money for installers and not as a subsidy for householders.

Expect the same results with the new retrofit grants announced today.https://www.irishtimes.com/news/politics/retrofit-grants-25-000-offered-to-households-to-help-insulate-homes-1.4795335

Well, as I've always maintained, it's a "free market economy".

If a supplier wants to build in the "grant tax" and quote people higher, it's really up to them to charge as they see fit. Ohh don't worry, I'm not getting soft in my old age, I still think it's ethically scandalous some of the quotes we've seen, especially the ones which effectively prey on people lack of knowledge of the solar landscape. They think they are getting a good deal, doing right by Gretta, but in reality they are being squeezed by the installer out of a couple of grand needlessly. Don't buy into the arguments of "superior panels" or "better after sales service".... it's nonsense lads.

Still, as much as it annoys and irks me.....they are totally entitled to quote and charge as they see fit. The same way we're totally entitled to pass on the names of solid value installers that we trust and recommend. If we save a few dozen people a few grand and onboarded some people who otherwise might not have gone solar......I feel that we've done a good service to the country!