My 16kWp Domestic System

KCross

mp3guy wrote: »

Just got word today ESB have acknowledged receipt of my new Form NC6, to dispell any myths about > 6kW installs with export limiting.

Which myth exactly?

Were some people saying you cant install >6kWp and you are saying you can as long as your inverter is <=6kWp... is that what you mean?

unkel

KCross wrote: »

Which myth exactly?

Were some people saying you cant install >6kWp and you are saying you can as long as your inverter is <=6kWp... is that what you mean?

I'm a bit confused myself. He has 11kW in two inverters but both can limit the export from what I understand from the OP

Not sure what they do with the NC6 forms BTW, I get the impression that they just acknowledge receipt of them and then just file them away without taking a closer look

mp3guy

KCross wrote: »

Which myth exactly?

Were some people saying you cant install >6kWp and you are saying you can as long as your inverter is <=6kWp... is that what you mean?

The myth purveying everywhere that you can't install inverter capacity above 6kW for 1P and 11kW for 3P without going the heavy duty NC5 direction, I see it all the time. My point is you can if you have an export limit.

unkel

I know you're correct, but I'm not so sure if you have proven that point, mp3guy. The ESB have just acknowledged they received your NC6 form, that's all isn't it? They haven't approved your install or anything like that.

mp3guy

unkel wrote: »

I know you're correct, but I'm not so sure if you have proven that point, mp3guy. The ESB have just acknowledged they received your NC6 form, that's all isn't it? They haven't approved your install or anything like that.

So you're suggesting despite the fact I've informed them of the specifications of my installation and that they've acknowledged these specifications and come back to me with no problems, they assuredly have an issue with it? Not to mention the fact that even before my initial 9kW install began they confirmed via email to my installer it was acceptable and the initial NC6 also passed without issue?

This is literally the channel the ESB provide for this, it even says on the micro generator page, after you've made your application:

Do not proceed if you have been notified by ESB Networks (within the specified time-frame) that you cannot proceed with installation of the micro-generator.

If I had to guess, I'd say up until now it has been a combination of people simply not sizing arrays bigger than 6kW, or being scared off by murky information being circulated around the topic of this limit.

unkel

You're assuming that their confirmation of receipt of the form is the same as them having checked it out thoroughly and have approved it. I'm just saying I would not assume that!

idc

Mp3guy with the size of your system what the lowest you've generated on your worst day? is the array big that you could go off grid?

unkel

I can answer that last question: no

You can't go off grid with only solar PV in Ireland (and no backup) unless your PV array and your battery are extremely big and / or you have tiny electricity needs.

From personal experience, in an average to large household with a 8kwp array and a 10kWh battery, you could go without consuming a single unit from the grid for a couple of weeks if you get weather like we have now.

idc

https://boards.ie/discussion/comment/117650832#Comment_117650832

I can accept that for most users but mp3guys is the largest home setup that anyone has on boards so far hence curious how much it generates on the worst day. I use 10-18kWh a day so curious how far that is off his worst day of production

mp3guy

https://boards.ie/discussion/comment/117649984#Comment_117649984

What month? And no, mainly because my wife likes to use the electric power shower which pulls 9kW, above what my battery can output. During Summer otherwise, yeah probably for a while. But don't have any good reason to go down that route.

idc

https://boards.ie/discussion/comment/117651140#Comment_117651140

Month doesn't matter - what is the lowest you ever produced on a single day?

unkel

Well, well, well under 1kWh even with a very large system

the_amazing_raisin

https://boards.ie/discussion/comment/117650832#Comment_117650832

Out of curiosity, if you had proper V2G capability in your EVs would that make some difference?

It'd be interesting with the likes of the Ioniq 5 if there's a charger similar to a Zappi which will not only charge your car from excess solar, but will also supply your house from the battery if it sees power being drawn from the grid

SD_DRACULA

It is almost released: https://wallbox.com/en_catalog/quasar-dc-charger

Price is a very ouch £4500 or thereabouts.

Also the car must support bidirectional charging, I was chatting to them and currently the only supported EV is the new leaf.

the_amazing_raisin

https://boards.ie/discussion/comment/117649984#Comment_117649984

The problem with going off grid in Ireland with only solar PV is Irish seasons

Off grid systems can't just match the generated kWh to the house's consumption because unless you can't store energy generated in summer for winter (unless you've a handy lake for pumped hydro)

I did the math some time ago with a similar sized array to mp3guy and while I could in theory generate enough kWh annually to match my usage, I still fall short in winter due to the combination of higher demand and lower output

Now if there's a semi decent FIT tariff, you can probably export enough in summer to offset your bills in winter so you're not paying any bills annually, but that's not the same as off grid

The other thing to watch out for off grid is instant demand. If your house is trying to pull 9kW, but you only have 5kW being generated from solar, then normally you'd pull from the batteries (if they have enough energy) or the grid. Without the grid, you'll need a bigger battery to match the required discharge rate, and likely a generator to give you on demand power when you can generate it from solar

unkel

https://boards.ie/discussion/comment/117652505#Comment_117652505

LOL, that system is not new, that's ancient! It was developed after the nuclear disaster in Japan 10 years ago. It only works with the obsolete Japanese CHAdeMO DC charging system.

unkel

Fun fact:

The average Irish household consumes 3,500 kWh per year

A 10 panel or so PV system south facing in a reasonably good area for PV in Ireland produces 3,500 kWh per year

SD_DRACULA

https://boards.ie/discussion/comment/117653346#Comment_117653346

Nope, they have a CCS version in the works but they're waiting for CCS to be officially approved for bidirectional charging which should be this year, just like FIT 😂

unkel

https://boards.ie/discussion/comment/117653462#Comment_117653462

It was actually me who posted that in the EV forum. About 3-4 years ago 😂

We're still waiting...

the_amazing_raisin

https://boards.ie/discussion/comment/117653350#Comment_117653350

Aye, but I'm not an average consumer, heat pump, electric cooking and 2 EVs, consumption is more like 8000-12000kWh per year 😅

unkel

https://boards.ie/discussion/comment/117653688#Comment_117653688

Install a big PV array so :-)

Mine is just under 8kwp and I have gas heating, gas cooking, mostly solar thermal water heating, no electric showers. But I still use a lot of electricity! Because of the current sunny weather and my large power wall, almost all of my units bought in the last week or so cost me just 4.79c / kWh incl VAT (night rate)

mp3guy

https://boards.ie/discussion/comment/117653910#Comment_117653910

Were you not subject to Energia's rate hike that shortly followed that low 4.79c rate?

unkel

Nope, my rates are fixed for the year. I guess I was lucky that I moved to their new EV rate as soon as it was launched!

the_amazing_raisin

https://www.boards.ie/discussion/2058169884/my-16kwp-domestic-system

So it's been about 6 months with some nice sunny weather, and a fair bit of grim cloudy days

Mind if I ask how the PV array has been performing so far?

mp3guy

https://www.boards.ie/discussion/comment/117800465#Comment_117800465

7.6MWh since March

bullit_dodger

That's..... impressive.

One thing that I'm interested in knowing is what's the typical % production on an overcast day. I know that's sort of a "how long is a piece of string" type question, but I;m generally speaking here. Not talking about length of day here, just the production rate % at a single point in time.

Are we talking ~20% on a totally overcast day (no breaks in the clouds) or higher/lower. E.g. if your max output is 16Kwp at noon on a sunny day in June, what would it be at noon on a typical overcast day in June, same sun angle, etc. ??

Just curious as to the rough level of absorption that the clouds have on panels. This is directed to everyone, but mp3guy if you can share that would be great too.

mp3guy

Easily 5% - 10% output on an awful day.

bullit_dodger

Thanks mp3guy.

I was expecting slightly more (ballpark 15-20%) When you say "On an awful day" I read that as "raining all day".... would that be accurate?

I'm sure there's probably charts up there on the web with this stuff, Infrared/ultraviloet absorbtion rates for depth of cloud etc.....but curious to see what people are getting. Real life if you will :-)

mp3guy

Raining all day, low dark grey cloud and mist/fog.

SD_DRACULA

Curious about the full dark clouds generation from your large system (no rain just overcast full day)

Not sure how it was in your neck of the woods but yesterday for me it was the worst day in August with 7kwh generated from well, 7kwp.

Would you get at least 15kwh from those days?