Solar for Beginners [ask your questions here]

Can I ask about cable specifications for a ground-mounted system. I am getting a lot of conflicting information from installers. I am trying to figure out what cables I need to run from the panels to the inverter. It is about 40m on two strings. Depends on who I talk to, I’m told one single 5-core 6sq cable in a duct to 10sq armoured cables in ducts for each string and everything in-between!

Would anyone know what the wiring specifications says for this? I think it is I.S.10101 and part 712 refers to PV

The SEAI code of practice just say that cables should be installed underground in suitable ducts. I had left a 4in sewer pipe under my concrete yard for this purpose but I can’t find out if I am allowed use it or not. SWA cable is expensive too and seems overkill to have armoured cables inside ducts?

Lot in this so let’s split it and enjoy getting solar, well work it

-East-west facing semi-d in Dublin – perfect for solar. Setup I have myself. E is morning sun, West is evening. Will get lower output than S but more evenly spread over the day

-BER won’t matter for solar, need a BER cert after the work to claim grant. But what the BER is doesn’t impact the grant or install

-Cost: Assume ~€1500 per 1kWp (1 KW of panels) after the grant. That’s crude but will give you a rough sense. Larger systems cost less per 1kWp as labour is a huge % of the cost

-Sell surplus back to the grid: We get ~20c FIT for units sent back to the grid (IE unused ones). Need a smart meter for that. Or a Day / Night meter (for what’s called deemed export, which is a set amount based on size of your solar inverter)

-EV: You don’t have one yet, but you’ll want a smart EV charger (like a Zappi) when you do. Can ignore that for now until you get an EV. Means excess solar goes into the car (needs to be in the driveway during core sunshine hours). About 1.5k supply and fit and get grant of €600 back. Don’t charge a large car battery from a small house battery (suffers electrical losses which means it’s wasted power, and wears the house battery more. Fine to do at times, but not every day forever more.

-Battery: House battery is a nice to have now that FIT pays well (which could change in time of course)

-Hot water: Can get a hot water diverter but it’s actually less expensive to heat the tank on cheap night rate if it’s a well insulated tank. Then get paid the FIT instead of sending those spare units to the hot water tank.

-Installer and getting up to speed: Solar PV Boards Members Installer Information — boards.ie - Now Ye're Talkin' & Interested in Solar PV? Read this FAQ first. — boards.ie - Now Ye're Talkin'. Post quote here when you have them: Domestic Solar PV Quotes 2022 - No PM requests - See Mod note post #1 - Page 163 — boards.ie - Now Ye're Talkin'

As much as you can A) afford B) roof can fit. Will be far cheaper to do now as labour is huge (roofers and sparks). Plus you get paid on what’s not used.

To get a sense of future usage: Our low-usage EV uses 2000kWh a year. Most EVs would use more I reckon due to higher mileage. Moving to electric heating (from gas) will use 1000s of kWh per year. Anything from 5000-10000 (finger in the air depending on what systems you get). If you’ve a gas cooker, you can move to electric. 

Got solar the other day, 1 panel short. The system and roofing is ready for an additional panel. Is it possible to buy and install myself as the company want to charge me a lot for 1 panel?

I got my Longi panels and microinverters delivered, looking to install them in the coming weeks. Thanks for the help here so far.

I'm thinking about AC-coupled batteries now. What AC-coupled battery storage do people have working with microinverters out there?

Yes, I get you.

I'm going down the microinverter route as I have an awkward roof layout, multiple aspects, shading, and the largest roof area would only support 3 or 4 panels, hence it doesn't suit a string inverter. Total installed kW would come to a max of about 3 to 4 kW.

I'm looking at ac-coupling for those reasons but I just read that my hoymiles inverters will support frequency shifting for battery charge management, so that's one element which I understand better now.

Thanks for the guidance on the Sofar, it wasn't coming up as an AC-coupled inverter in my searches, but maybe I overlooked it.

Maybe I'll join you in 15kW-o'clock in the future.

Victron's quattro or multiplus inverters as mentioned here.

A few others, but its not easy sorting out the AC from the MPPT types.

How do I turn off water heating when we are away from the house for some days? I'm happy to export all the surplus.

Can someone say what happens when the Eddi diverter is OFF?

The manual just says that it's off, no more.

I presume that means it does not heat the water. But does it export? The screen goes off too so I can't see.

Thanks

That's a very clear way to put it a thank you @bullit_dodger

You need to look at the spec sheet of both inverter and the panels you are fitting, but in general you'd get about 12 panels on a string, so 24 panels in total on your inverter (but it probably can't handle all that DC power)

Cost of fitting extra panels is relatively cheap when the lads have to go up on the roof anyway. So I would generally advise to get as many up as you can. It's a relatively easy calculation to guess what you are not using times the FIT vs the additional cost of the panels, but you will likely kick yourself in due course if you don't max it out

Also most installers have several months waiting time for installs now. You're very optimistic to get it all done in the next 2 weeks and have the NC6 processed by the ESB within that time too. Or are you installing DIY (and not get subsidy)?

AFAIK you can submit the NC6 yourself, @Mr Q I think submitted his own one. In advance of the install.

Anybody know an Irish supplier of BC01 AC mains connectors, I left myself short one for my Hoymiles inverters?

This is a great thread lots of info. I've just accepted a quote from a solar installer. He told me that the battery isn't worth getting and I can export excess to the national grid for electricity credit. That's grand but I don't have a smart meter right now. He says ESB plan to upgrade all meters to Smart within 4 months of going solar and offer them to every house in the country in 2024 (I'm always sceptical about what governments and companies tell me will happen by a certain date). In the meantime he reckons the electricity provider will credit me with an 'estimate' of how much electricity I'm exporting. I don't have a hot water tank, I use a gas combi boiler so I can't divert to hot water, I will depend on being able to export with no battery storage. Am I being mislead, any contrary opinions?

Thanks, it's a 24hr meter at present. It'll be an 8 panel system 400w panels. I'm in work most of the day 3 days per week but I have smart appliances, washing machine, dishwasher, slow cooker etc that I can set to start whatever time I like. So I can time most of my usage to coincide with peak solar output.

Ah yes, thanks! It's hidden. I needed the female one... saves me having to go to Amazon!

Edit: 16 EUR delivery - shaggin' 'ell.