solar panel and the way they might heat ye?

[Ivor]

Once more I seek guidance

I’m looking at installing PV panels to make use of the great sunshine here!

We don’t use huge amounts of energy so looking at a mid-sized system
4.8kWp (12X400W) with 2.4kWh storage with MYEnergi EDDI water diverter
Cost including VAT is. €13154
Grant applied from SEAI €2400
Final Cost €10754
To upgrade to the 410W Jinko N type panel (enhanced warranty of 25 years) simply add €30 per panel.

There will also be an EV charging point.

As I have a wood burning stove which heats the downstairs and provides ample hot water the panels will provide electricity to the hot water cylinder when we won’t be lighting fires. I may also add a Willis. We’ll see.


As we have 3 of 4 upstairs bedrooms not in constant/regular use I was going to go for infra-red panels with separate remote controls. A converted integral garage will also have an IR panel as it’s now the “grandad cave”!

I’m going to add batteries as we are now quite remote and a blackout, while unlikely, is a horrible idea! It does happen. Also, it’s nice to know there’s a bit there if needed.

I know a few here have been down this road so your thoughts are very welcome….

[phelixoflaherty]

This thread is very informative .

https://www.boards.ie/discussion/205821 ... -post-1/p1

[Adrian]

Sounds like a very interesting project going on there Ivor.

I don't have much to offer, but if I may I would suggest the batteries are kept away from the house.

Lithium batteries if they overheat / go on fire they can be very difficult to extinguish.

No point in spending money to save a few hundred bucks a year if you are risking burning down your entire home not to mention putting the lives of your family at risk.

I know of one home which had a PV array installed, and the battery is located in the attic! Total madness.

Best to have a shed / dedicated outhouse if you are going to go seriously into batteries.

[Sligolad]

Regarding batteries!

Just make sure the batteries are lithium iron phosphate battery (LiFePO4 battery) or LFP batteries if you go for an internal install.

Most installers should be using these LFP battery packs for attic installs given their fire safety over the common Lithium Ion batteries.
Lithium Ion battery packs should not be placed in an attic.

I have 16kwh LFP battery pack in the attic for several years now and my real fire risk is from the Lithium Ion batteries in Laptops, phones, power tools, etc. lying around the house.

[Fran]

Ivor - I cannot make the batteries pay here but I have an unusual case with the heatpump. I would get most from the batteries in the winter time, but that is exactly when I wouldn't have the solar to recharge them. So I can't see the benefit. Also, batteries are about 80% efficient - If you get you micro-generation connection, it looks like the feed in tariff will be about 60% of retail. You could think of the grid as a 60% efficient batteries of infinite size - but without having to have the battery cost.

So the batteries are a "no" from me. But the hot water heater could be a great saving. When we got our panels in 2018, I had the capital repayment time at 8-9 years, and I think that has probably accelerated now with the cost increases. Getting the most from them means you need to use electricity as you generate it - ideally nothing would flow to or from the grid. That means putting on domestic appliances in series - so let the dishwasher finish, then put on the washing machine on and so on. Never works as easy as that, but you get the idea.

I would also say having batteries is no good for a power cut - you will not run a hob, oven, etc from them for any length. Power cuts are so rare now that its hard to see the value. It might make sense to have it to keep a circulation pump running if you had a back boiler etc. though. A UPS on the circulation pump might be the easiest way to handle that though.

Lots to think through and work out here!

[Ivor]

Thanks for all the info lads, especially on the viability of batteries and the safe spec. I can easily have them in an separate shed rather than an attic. If we go down that route...

The blackouts are rare but we had two shortly after we arrived! I thought maybe we hadn't switched the a/c over or something... talking to neighbours they are infrequent but can happen. Switching from the Grid to batteries is simple enough and would give us some power for a night or whatever.

Much food for thought alright... hopefully I can heat it up :)

Adrian I'm in your neck of the woods now, will give you a shout soon!

[Adrian]

TBH there is no substitute for insulation. But to get a good standard can be quiet involved. Attic insulation, thermal wrap of building and high spec windows, which may require new sills to be fitted?

I'm not a fan of putting electrics in attics, as attic spaces don't normally have divisions nor smoke alarms fitted. They are also dry and full of combustible materials. Get a fire in a attic and it will go right across the top of the entire house. A fire in a kitchen / living room can normally be contained for a while, giving you a chance to put it out. All it takes is a loose connection which can overheat and the place is at serious risk.

If you have space around the house (large garden etc) then I would place the array on a metal frame on the ground. Far easier to install, repair, inspections & maintenance etc. Probably cheaper too.

[Ivor]

TBH there is no substitute for insulation. But to get a good standard can be quiet involved. Attic insulation, thermal wrap of building and high spec windows, which may require new sills to be fitted?

There isn't but... trying to get the insulation fitted is a nightmare. The good guys are busy! I hope to get this checked and done before the PV panels are installed (early Nov). The building itself is in good nick and the windows are still under guarantee.
The batteries are "top of the range" and are safe, having them in a nearby "shed" obviously requires a communication line.
No real advantage to siting the panels at ground level, I have the roof space at a good angle on a bungalow and the extra cost wouldn't be worth it.