Solar for Dummies.

bullit_dodger

Yeah, that might work, although you'd want to put the 5.2kwh on the AC coupled one as that's limited to 3000w charging. Not sure about if you could get each of them dumping in parallel. I would assume yes, but not sure

micks_address

https://www.boards.ie/discussion/comment/122036832#Comment_122036832

hardly worth it though to save a euro each day for december/jan… be a long time breaking even!

slave1

https://www.boards.ie/discussion/comment/122037538#Comment_122037538

this, think carefully about increasing Nov-Feb generation, the angle of sun and duration of sun is very poor so payback questionable on any spend

micks_address

https://www.boards.ie/discussion/comment/122038403#Comment_122038403

not looking at generation.. battery charging only

bullit_dodger

https://www.boards.ie/discussion/comment/122038553#Comment_122038553

Yeah it's a borderline case mick. If I had the money spare, I'd probably do it. If it's a euro a day then that's obviously €365 saved a year. How much would the AC coupled inverter with installation be? I'd imagine less than €1800? So your 5 years payback on it which is (roughly) inline with most things solar. The main thing for me would be that your bills in winter would be less, but it's a definitely debatable question

mjatkey

Hi,

Has anyone had any experience with either of the below diverters (cheaper version of the Eddi).

On Ebay both are pretty much half the price of Eddi, was thinking of getting one and getting sparks to add on the day of PV install.

Charge + Solar diverter (Immersion Diverter, iBoost alternative)

Solic 200 Solar Immersion Controller Power Diverter Earthwise Products

Thanks

graememk

https://www.boards.ie/discussion/comment/122060684#Comment_122060684

Iboost is noisy Vs eddi is silent. (They must have found the cheapest fan they could find for it.)

Also the iboost is supposed to be very noisy electrically too.

Solic isn't configurable(no export Margin for hybrid inverters)

mjatkey

Thanks graememk, I'll steer clear of either of those.

mjatkey

Hi,

Slightly off topic, (point me in right direction if there is a more appropriate section).

Just trying to get my head round all the pieces and how they fit together and what you can do with automation when it comes to solar PV.

So as I understand it the panels are connected to the inverter as are the batteries and obviously the house consumer unit.

So if the panels are producing electricity the inverter will supply power to the house first and then power to charge the batteries if the house load is being meet.

First question, do the batteries have to be fully charged before power is sent back to the grid, or is that configurable?

Do you have to keep the batteries at a certain charge level?

Can you choose to only charge the batteries from the panels (we don’t currently have a TOU electric contract) so we would be buying electricity for more the FIT?

I’ve seen a lot of talk about Home Assistant and automation; we already have a lot of smart switches for controlling lights, pond pumps, tv’s etc was wondering if adding HA is worth doing, is there a cost associated with using it and how tricky is it to set up?

Thanks

graememk

https://www.boards.ie/discussion/comment/122078982#Comment_122078982

First question, do the batteries have to be fully charged before power is sent back to the grid, or is that configurable?»

Yes, this is the default behaviour. Unless you make your own automations/controls to change this (on the advanced end).

Do you have to keep the batteries at a certain charge level?

No, But generally they are discharged to 20%. If leaving them for an extended time possibly advisable to have them at about 50%. This can also be set in the inverter as a minimum State of charge.

Can you choose to only charge the batteries from the panels (we don’t currently have a TOU electric contract) so we would be buying electricity for more the FIT?

You can charge from the grid too, if you have a Time of use plan, For less than your FIT… and then discharge to export for the FIT.

I’ve seen a lot of talk about Home Assistant and automation; we already have a lot of smart switches for controlling lights, pond pumps, tv’s etc was wondering if adding HA is worth doing, is there a cost associated with using it and how tricky is it to set up?»

Cost is a little bit of hardware, and your time. But generally its worth it. It can bring all the separate smart devices under one central control.

mjatkey

https://www.boards.ie/discussion/comment/122079031#Comment_122079031

Thanks, yeap most probably will switch to TOU contract next year when contract renews.

ColemanY2K

When plugging in the "Installed peak PV power [kWp]" figure into PVGIS should I use the size of my array (8kWp for example) or limit it to the size of my inverter (5kW) as that's what production will be limited to?

graememk

https://www.boards.ie/discussion/comment/122084126#Comment_122084126

Id use the 8kWp as the vast majority of the time you'll not be clipping.

ColemanY2K

https://www.boards.ie/discussion/comment/122084136#Comment_122084136

Thanks.

It seems I'm consistently undershooting PVGIS by a significant margin. It's a real head scratcher.

slave1

shading?

10-10-20

https://www.boards.ie/discussion/comment/122084156#Comment_122084156

On the basis of which metric, the solar generation at the inverter or power returned off the inverter into the house and grid? Because the latter would hide some of the losses between conversion from solar DC to battery DC and back to AC out.

And as @graememk said, any shading at all would cause loss - and haven't we had endless amounts of natural shading from the big diffusers in the sky this year.

ColemanY2K

https://www.boards.ie/discussion/comment/122084239#Comment_122084239

There is a little bit of that in the morning when the smaller array is in the shadow of the house but by 9am it's in full sun and at around 4:30pm a shadow from an adjacent ESB pole comes into play on the larger array. However the Solis graphs don't show any major reduction in production in the afternoon.

There's a 150kWh variance with PVGIS in April and 100kWh variance in March.

Perhaps it's to do with clouds and the generally poor weather for a large part of the previous two months.

It'll be interesting to see how spring 2025 fairs.

slave1

Do remember this year to date is worse than last year and last year was worse than previous year so the weather recently is not hitting the mark

graememk

https://www.boards.ie/discussion/comment/122084156#Comment_122084156

It's been a brutal spring though.

Only got going on tillage in the last week.

It's may now, so first day of summer.

SouthWesterly

Has anyone used either of these for their panels.

Has anyone an opinion?

bullit_dodger

https://www.boards.ie/discussion/comment/122085175#Comment_122085175

When you say your consistently missing the mark, what's the percentage deviation? You list 150Kw for April short, but if you were producing 1000kwh a month that's not so bad. However if you were expecting 400Kwh that's a lot then. I guess it's all relative. Yeah, I guess I could take your details and plug them into PVGIS myself, but you know…..lazy and all :-)

Best thing to do is look for similar sized installs on the forums (reasonably) close to where you live. Say 30-40Km. That way you will help rule out weather deviations, and then work out what the generation per 1Kwp is for them and you and see if you get reasonably close. Bear in mind you will also need them to be the same rough orientation. No sense in comparing a E/W split with a S array - or at least it's not desirable anyway

con747

https://www.boards.ie/discussion/comment/122085967#Comment_122085967

The plastic ones are used a lot on flat roofs and ground mounts without any issues, I don't know about the other ones but can't see why they wouldn't be okay unless they are not galvanised. Just make sure there is enough weight in them!

SouthWesterly

https://www.boards.ie/discussion/comment/122086444#Comment_122086444

Thanks. They're Galvanised. The blurb says good for 20 years.

Its either build a block base to raise the plastic ones up a bit or use the galvanised.im on a windy site on a mountain

con747

I'd go for the plastic ones but that's just my opinion others may have a different view. Panels last for up to 30 years+ so I would hope the plastic bases last the same.

SouthWesterly

https://www.boards.ie/discussion/comment/122086592#Comment_122086592

That was my thinking but at 18 degrees I was wondering is it a bit low.

con747

https://www.boards.ie/discussion/comment/122087461#Comment_122087461

Put the details in here to see how much it will generate. https://re.jrc.ec.europa.eu/pvg_tools/en/

SouthWesterly

https://www.boards.ie/discussion/comment/122087509#Comment_122087509

Your right. Less than 100 KWh over the year on a 2kw array.

Thanks for your help