Solar for Beginners [ask your questions here]

slave1

April or May are the strongest generation months in Ireland so will greatly assist heat pump, this year March was excellent too. Forget about Nov-Feb

Commissar

Can't find the answer here so asking my own situational question; What do I need to put excess Solar energy into the radiators?

Quite recently got a system installed and, while I'm very happy with it, I misunderstood initially - I thought a Hot Water diverter would also heat the radiators (The oil heating heats the taps & radiators so I made a silly assumption).

Obviously that's not the case so now I'm looking to fill that gap, especially as home usage stands around 30%.

What do I need to send the energy into the heating system/radiators? Would my electrician be the guy to call about this?

graememk

https://www.boards.ie/discussion/comment/119070990#Comment_119070990

Well...

As the hot water divert is just an immersion controller in your domestic hot water tank, it will only heat that.

I am doing something like what your asking but it's quite "off piste" and doing it with the help of a plumber friend.

I've got a buffer tank (500L) that has 2 immersions that I'm going to plumb directly into the radiator plumbing and with some wiring and pipe stats for some basic logic. Tank will be heated with an eddi, should store in the region of 20kwh of heat

Normally when the house calls for heat it will fire up the oil burner, the plan is that when there is a call for heat, if the tank is hot enough, it will pull heat from the buffer tank, If there isn't it will come straight from the oil burner.

I'll prob put a mixer valve on the output too to limit the temperature coming from the tank

Commissar

https://www.boards.ie/discussion/comment/119071509#Comment_119071509

Thanks for that explanation - you've cleared up a few misconceptions. for me.

Granted water takes a lot of energy to heat, but of the 21kWh my small system has generated today (Summer, I know), 15kWh has disappeared into the grid. Would the effect of that 15kWh be so negligible that it's not worth considering the house heating system? I can't imagine diying it myself and if this really isn't a thing I can get an electrician/plumber to do...

graememk

https://www.boards.ie/discussion/comment/119071669#Comment_119071669

Its about a litre or 2 of oil!

And it's not really something that's "off the shelf" either.

garo

Do you have a battery or an EV? Those are easier and better to put the excess electricity into.

SD_DRACULA

There is one solution that I am also following closely, the guys from https://sunamp.com/ do material change batteries which at the moment can be used to give DHW from solar diversion (eddi), you basically use this instead of a hot press but they said towards the end of the year those batteries will be able to be plumbed directly to the rads/boiler as well.

And yes excess solar is not a thing in winter but you still need rads on until May more or less and who knows, night rate electricity might end up cheaper than gas anyway.

fuse

I've learned lots the last few days reading through everything solar here.

Also this video helped tie everything together.

https://www.youtube.com/watch?v=VUrGvwphJ3I

My main concerns now are whether I need a battery or not (current prices turning me off).

Currently consuming 5,500 kW per year on average, E/W facing roof on a semi-d.

Also, any recommendations on a cheap but effective way of monitoring my energy use beyond meter readings (maybe CT Clamp device)?

thanks

Ubbquittious

https://www.boards.ie/discussion/comment/119071509#Comment_119071509

Great ! I love off-piste

yankinlk

https://www.boards.ie/discussion/comment/119136105#Comment_119136105

That is an awesome video - we should add it to the FAQ maybe. :)

Jonathan

https://www.boards.ie/discussion/comment/119144026#Comment_119144026

😉😉

Yeah, will add to FAQ shortly.

John mac

https://www.boards.ie/discussion/comment/119136105#Comment_119136105

@fuse Shelly , has 2 ct clamps , https://shop.shelly.cloud/shelly-em-50a-clamp-wifi-smart-home-automation-1#143

WHL

Hi. I need to get my act together and get a few more quotes. I have been analysing old bills. My daily usage ranges from 14.5 kWh in summer to 19.5 kWh in winter. I plan to get an Eddi for hot water and a battery my roof faces due south. How many panels and what size battery would people recommend. I don’t want to over-spec

con747

https://www.boards.ie/discussion/comment/119165959#Comment_119165959

Have a look at the spreadsheet listed here https://www.boards.ie/discussion/2058234656/renewable-energies-forum-key-threads#latest

It gives peoples system size and performance. You can gauge your needs on that. A couple of other useful threads there as well to guide you. If it was me I would get a 5-7kw system with 6kw diverter and minimum 5kw battery, others will advise to go as big as your roof allows but it depends on your budget.

fuse

I'm in the process of getting quotes for system and I have a pretty basic question about the eddi diverter.

Currently I have water heating via gas boiler on a schedule on my google nest. Say 6-7am and 4-5pm every day.

If I get solar set up and the eddi running - and I leave the gas water heating as is... In winter time - the gas will probably need to heat the water in the morning and from spring/summer I can expect the water might be heated by 7am via the eddi. So the gas boiler will detect this and just decide to not fire up if not needed? Or at least just top up the water to the target temp?

Jonathan

https://www.boards.ie/discussion/comment/119167258#Comment_119167258

Have you got a boiler stat on your cylinder? If yes, boiler will only fire when temperature below set point.

fuse

https://www.boards.ie/discussion/comment/119167399#Comment_119167399

Yes - good question 😊

There's a stat on the pipe going into it. It's a Joule Cyclone CY200L Twin Solar - so it's solar ready by the sounds of it!

Thanks

Lob1

Can I install a 4 kw system and battery using an inverter with zero grid feed in can I install without using a RECCI Eletrical. Not interested in grant. Thanks

graememk

https://www.boards.ie/discussion/comment/119323064#Comment_119323064

Totally off grid.. yes

Connected to your consumer unit. No.

Gorteen

This may be a silly question, but what is the sequence of benefit from PV panels?

Is this the order in which the following occur?

1. Charge battery for domestic supply
2. Heat water in cylinder
3. Excess energy to grid

I notice that while I have lots of hot water during the day, the next morning the water is just above luke warm. I had expected much more hot water but that seems not to be the case

Jonathan

https://www.boards.ie/discussion/comment/119360682#Comment_119360682

Any chance your Eddi is connected to your sink element rather than the bath element? How big is your cylinder, and many kWh does it 'store' before it reaches max temp?

yankinlk

https://www.boards.ie/discussion/comment/119360682#Comment_119360682

Not a silly a silly questions at all.

You have the order exactly correct 1,2,3.

Have you setup the eddi to give a "boost" in the morning at all? I have a D/N meter so I boost around 6am on the cheaper rate. I also have a 5kW battery and this time of year - the boost runs off battery rather than drawing from grid. But this would depend on the size of your battery and array - YMMV.

If you did NOT setup any boost at all - then your tank will cool from evening time thru until morning and the first shower might be OK but it could quickly empty - depends on the size of your tank as well. You are correct that your tank wont start to warm up in the morning until the battery is full or the sun exceeds the maximum rate of the battery and grid combined.

BTW I have an entire thread on maximizing this setup : https://www.boards.ie/discussion/2058254838/limit-eddi-to-battery-max#latest

Gorteen

https://www.boards.ie/discussion/comment/119361164#Comment_119361164

Switch is set to bath.

Ordinary size cylinder.

kWh store??? No idea!

Gorteen

https://www.boards.ie/discussion/comment/119361334#Comment_119361334

How do I set up the EDDI for a morning boost?

My battery is a Puredrive 5 kW

My panels give 6.9 kW

All of the above means nothing to me!!!

Ha Long Bay

https://www.boards.ie/discussion/comment/119361657#Comment_119361657

Do you have the myenergi app installed? If so on the home screen click on the eddi then select tank 1 or whatever it's called. Then click schedule and set the time there.

Jonathan

https://www.boards.ie/discussion/comment/119361627#Comment_119361627

The Eddi screen should show how much kWh has been diverted today.

This calculator will give you an idea how much energy your cylinder should be storing.

https://www.omnicalculator.com/physics/water-heating

See example below (1L water = 1KG):

steamdave

https://www.boards.ie/discussion/comment/119360682#Comment_119360682

What times are you heating your water in the evening? Do you need to use night rate or battery power to give your hot water a boost during the night/early morning?

Is the thermostat set to the ideal temperature for your use? If Yes, it sounds as if your tank could do with more efficient lagging. As an example, my hot water cylinder loses 0.2 deg C per hour after heat is shut off.

Dave

bullit_dodger

https://www.boards.ie/discussion/comment/119361747#Comment_119361747

Just to expand a little on what Jonathan says.....this part of the Eddi screen tells you how much Kilowatt hrs have gone into the tank on that specific day.

Obviously early in the morning this will be 0.0kWh as the sun comes up, but during the day as the Eddi draws some excess power...(especially if its sunny) the number will increase. Above in my picture which I took this evening, I can see that today my Eddi put 1.28Kwh of energy into the tank. This can give you an indication of how much energy you are diverting.

It is possible to go to the menus, but the above is the "quick-n-easy" way in looking

MAULBROOK

https://www.boards.ie/discussion/comment/119360682#Comment_119360682

What type of hot water cylinder do you have. Can you see how much power your diverter is sending to the immersion.

Gorteen

https://www.boards.ie/discussion/comment/119362243#Comment_119362243

Normal HWC. Today it sent 2.86kWh to the immersion.

https://www.boards.ie/discussion/comment/119361676#Comment_119361676

I was told that SolisCloud is better, but I haven't succeeded in getting it set up to give me info on the phone.

https://www.boards.ie/discussion/comment/119361851#Comment_119361851

I'm not "heating the water". I'm just assuming the PV panels will heat the water. I don't have smart meter yet. Existing meter is in place since house was built in 2000.

vistaphotos

https://www.boards.ie/discussion/comment/118984052#Comment_118984052

Eastern roof has loads of room, Western roof has less space. Most installers have suggested E/W split.

One is suggesting some panels on the smaller Southern roof "X" which likely need optimizers anyhow due to tall chimney "Y".

I think the idea is that due to smaller space on the Western roof it may be necessary to put panels on the Southern roof to match the overall number of Eastern panels, with benefit from Southern panels during the middle of the day. What would be impact later in the day when sun is in the West?

How should that be configured in terms of strings? Link the Southern panels and Western panels into one string, with Eastern panels on their own string? If linking S & W should all of those have optimizers?

Is E/W/S overcomplicating things and would an E/W split be simpler.

Thanks

bullit_dodger

You ONLY need optimizers where you have shading/shadows cast on a panel, or a number of panels.

it's hard to tell really from the piccie, you'd need to see it in person, but "x" and the south facing roof (not labeled) to the bottom of the picture would be a good place for a bunch of panels on 1x string. You can do that as they are all orientated the same way, albeit, you'd need optimizers on the panels on "x" as you say you have a chimney which could be casting a shadow.

Then you could have a bunch of panels on East.

I'm sure others here would have some ideas too?

vistaphotos

https://www.boards.ie/discussion/comment/119372193#Comment_119372193

Thanks. Structurally southern roofs are smaller and not as strong as main western roof so not inclined to load with panels. This means EW may be better option. Have heard that W better than S for evening power any merit in that?

slave1

https://www.boards.ie/discussion/comment/119374606#Comment_119374606

As the sun is in the W in the evening then power will be more, E more in the morning, S most during peak midday hours, North 50% of South

shakeymathuna

https://www.boards.ie/discussion/comment/118423544#Comment_118423544

Re your offer of assistance to forestall being ripped off. I am new to this and based in Cork. Could you point me in the right direction. Thanks.

MAULBROOK

https://www.boards.ie/discussion/comment/119394730#Comment_119394730

As requested sent.

Barrak

Question regarding Invertor/Battery installation...

Had 5KwH PV installed last week E-W array. Commissioning/intstallation of inverter and battery (Huawei Sun Invertor/Luna Battery). I need to decide the location of the installation. Installer had suggested the attic however I would have concerns about putting a lithium ion battery up there. My two suggestions were in a utility room downstairs or externally mounted on a gable wall (north facing and relatively protected from weather) and putting a fixed canopy over the system. Both options have merits: inside would be more secure from theft etc while externally would negate and fire risk with the battery (though maybe i'm overreacting!). I would be grateful to hear from anyone who might have been in a similar pickle or has experience in the matter.

Many thanks in advance!

DC999

https://www.boards.ie/discussion/comment/119409484#Comment_119409484

I'm looking for the exact same advice please (caved and bought a battery!!!). Seems the LG Luna is outdoor rated. My options are attic or beside gas boiler (seems like a bad idea!!). No utility room. Small gaff so no where else for it to live inside. Or externally mounted on a gable wall (relatively protected from weather). Don't have a shed for it close to consumer unit. It's a large enough unit the installer said. Will be 5/6kwh model.

con747

https://www.boards.ie/discussion/comment/119409484#Comment_119409484

I put mine in a small lobby at the front door where the fuse board is because of access to the attic was a nuisance and I'm glad I did! You will be able to monitor it instantly and check alarms as they happen in real time not delayed like the app shows. If you need to access any settings like charging times for the battery in winter it makes it easier as well. I wouldn't put the battery outside unless it is in a garage or somewhere the temperature is fairly stable in winter, batteries don't like the cold!

DC999

Fair point on an outside wall in winter. They have a heating unit in them for that. But means they are burning juice to keep the temp in the right range - so that's an efficiency drop.

Dumb Q. Any safety concerns with any solar batteries being in houses for air quality? We're not supposed to have gas boilers in bedrooms now due to what's we're breathing from them. But that's only something being flagged more recently. Asking in case batteries may be similar. Are batteries fully sealed units so what's inside them can't exhaust into what we breathe? There's gotta be some airflow to cool them, but maybe that's outside each cell??

con747

https://www.boards.ie/discussion/comment/119409794#Comment_119409794

I wouldn't be worried about gases leaking from them. I'm sure more tech minded boardsies will explain in more detail!

Black_Knight

Hi all. Question about the an off grid "failover". Is that possible with a Solis hybrid inverter?

I'll be getting PV with a 5kW Solis hybrid inverter and a 5kWh battery installed this year. I know by default home PV shuts down in event of a power cut, but is there a way to have a manual cut over, and does the Solis inverter support that?

graememk

https://www.boards.ie/discussion/comment/119414401#Comment_119414401

Yes, My parents have it,

They were getting a new consumer unit at time of install too.. The old one was older than me!

There is a changeover switch beside the consumer unit where the mains and the backup supply from the solis goes into, and that feeds the consumer unit. Has 3 positions, Grid, Off and Backup. You also need 2 cables going from the solar inverter to the consumer unit location.

There is 2 (3?) steps to do theirs,

Move to Off position,

At the solar inverter, there is a mini consumer unit, there you turn on a mcb for the backup supply, that operates a NC contactor which disables the gird supply to the solar inverter.

Back to the change over switch, move that to backup and we're up and running, completely off grid.

The reason for the extra steps is to keep the fireman switch activated, so the solar panels still generate electric. without that step they would be on battery only.

AckwelFoley

Is that something "as standard" with the solis? The idea that there's no off grid in the event of a power outage is a bit of a bummer for me. It would be great to have the off grid backup considering the times we are in and potential outages.. run lights etc would be great

silver_sky

https://www.boards.ie/discussion/comment/119418258#Comment_119418258

Not standard, you'd need to request it from the installer as there's additional wiring and switches. The solis hybrids should all have the capability though. I've the same setup on mine. Two steps to switch over to backup and it's running the house then. Max 13A total.

Usually its just a single socket that the installer will put on that port. Not a huge amount of use though.

Barrak

So we had the installers out today commissioning the inverter. Decided to go outside on a gable wall relatively protected from the weather. Huawei 5kW inverter for the 5.6kWh E-W array. All need to do is pop a small canopy over the inverter. Very happy with how it turned out looks wise, all parts IP65 rated for water too. Battery should be delivered and installed soon & should nicely cover any troughs during the day and our usage overnight.

DC999

We did same last week with Huawei inverter. Installer said they prefer to install outdoors. Solves the issue of overheating in the attic. Or same with a lot of heat wherever they are. Or loud fans depending on inverter.

We don't have any housing for them. They are rated for outdoor. Doesn’t look very pretty on side of house though. Panels all run back the them kill switches there too. But I reckon it's better for them to run at a lower temperature.

MAULBROOK

https://www.boards.ie/discussion/comment/119425799#Comment_119425799

Any Photos

Barrak

That’s our one anyway sorry can’t figure how to get it right way around. Waiting on battery to be added in few weeks.

Lob1

Hi All

would anyone of you have a photo of the ct clamp and check meter installation. Need to install one and have a total mental block on how to do it. Thank you