solar PV system

TheWonderLlama

around 8k for the system.

I have a little trick on my plumbing though. When water in cylinder gets to temp, a pump kicks in and pumps it through the rads, heating the house. With the diverter, this should happen without the need for oil burner kicking in. (fingers crossed)

bunderoon

What ltr capacity is your hot water cylinder and Kw of the immersion element?

unkel

TheWonderLlama wrote: »

around 8k for the system.

Not the worst, but certainly not the cheapest for your setup (see the quotes thread)

TheWonderLlama wrote: »

When water in cylinder gets to temp

What temp? From now on until sometime in March, your full cylinder (what size?) will never reach even 50C except on a dozen or so very sunny days.

TheWonderLlama

definitely not the cheapest, but the installer was recommended, so that's worth more.

Have the stat set at 75, but i have a solar thermal panel also, that usually gets it to 35-40. Diverter should help to get it to temp then it heats the radiators.

garo

Congratulations. I agree with others that the 1.5k per year saving figure is wildly inflated. €400 is a more realistic figure. I had the system installed two months ago and can already see the impact shorter days are having. And with a 2.4kWh battery you won’t get much beyond 10pm most days. You will save a bit more due to the diverter + special plumbing but doubt it will be more than 100€.

Out of curiosity, do you pipe bathing water into the rads? Where does it return? You original post has me confused as to your setup with solar thermal and a diverter. I would have through the diverter heats up the hot water cylinder directly rather than the water circulating in the roads.

KCross

I think you're in for a cold winter!

rolion

TheWonderLlama wrote: »

around 8k for the system.

I have a little trick on my plumbing though. When water in cylinder gets to temp, a pump kicks in and pumps it through the rads, heating the house. With the diverter, this should happen without the need for oil burner kicking in. (fingers crossed)

Very nice ideea...

Tried to do myself but my solar cilinder was with only one coil.
With two coils, you can have the secondary circuit and achieve as you explained.

wexfordman2

TheWonderLlama wrote: »

around 8k for the system.

I have a little trick on my plumbing though. When water in cylinder gets to temp, a pump kicks in and pumps it through the rads, heating the house. With the diverter, this should happen without the need for oil burner kicking in. (fingers crossed)

Sounds interesting good luck with it and let us know how you get on. Ine if your challenges re using the diverter to what your roads, is that you will be looking for this when you get the least amount if solar and need the max heat.

That will be a challenge.

TheWonderLlama

garo wrote: »

Congratulations. I agree with others that the 1.5k per year saving figure is wildly inflated. €400 is a more realistic figure. I had the system installed two months ago and can already see the impact shorter days are having. And with a 2.4kWh battery you won’t get much beyond 10pm most days. You will save a bit more due to the diverter + special plumbing but doubt it will be more than 100€.

Out of curiosity, do you pipe bathing water into the rads? Where does it return? You original post has me confused as to your setup with solar thermal and a diverter. I would have through the diverter heats up the hot water cylinder directly rather than the water circulating in the roads.

Separate circuit to the bathing water.

Will be interesting to see over winter how much it does save. I take your point about shorter days alright.

TheWonderLlama

rolion wrote: »

Very nice ideea...

Tried to do myself but my solar cilinder was with only one coil.
With two coils, you can have the secondary circuit and achieve as you explained.

yeah, you need the double coil for this. Mine is actually triple as there's a range as well. My old man, who is a bit of a genius on these things, set the whole thing up. Now we get to test his system to the limit.

garo

Thanks. Yes it looks you will get more out of your system than most of us. But would be interesting to see what winter brings. Not sure what your usage profile is and if someone is at home during the day but I am willing to bet the PV bit doesn’t reduce your bills by more than 6-700€ p.a.

unkel

garo wrote: »

Thanks. Yes it looks you will get more out of your system than most of us.

He won't. The same amount of water is heated with his diverter and thermal collector whether he lets that water sit in the cylinder (for later use in the shower) or if he pumps it through his radiators. You can't "magic" any more energy out of that heated water (first law of thermodynamics)

Be different in the middle of summer when you could heat your cylinder several times over every day. His radiators would be nice and hot as well as his hot water :pac:

garo

I was being generous there Unkel but you seem to be in no mood to yield any quarter.

physioman

Hi has anyone used lead acid batteries for storage. From what I can gather they are obviously cheaper but the life span is 3-5 years. Am very new to this but how many batteries would it take to store 10kwh?

victor8600

physioman wrote: »

..... Am very new to this but how many batteries would it take to store 10kwh?

http://all-about-lead-acid-batteries.capnfatz.com/all-about-lead-acid-batteries/lead-acid-battery-fundamentals/amp-hours-vs-kilowatt-hours/

If you have a 100Ah battery, then 100Ah x 12V = 1.2KWh

10/1.2 = 8.3, so you would need 9 batteries.

I found this series of videos interesting: https://www.youtube.com/watch?v=m5wv4HcRNKw

physioman

victor8600 wrote: »

http://all-about-lead-acid-batteries.capnfatz.com/all-about-lead-acid-batteries/lead-acid-battery-fundamentals/amp-hours-vs-kilowatt-hours/

If you have a 100Ah battery, then 100Ah x 12V = 1.2KWh

10/1.2 = 8.3, so you would need 9 batteries.

I found this series of videos interesting: https://www.youtube.com/watch?v=m5wv4HcRNKw

Thanks. So just googling quickly the price of 100ah battery is 400 euro x 9 = 3600. 10kwh lithium battery is 10k? So lets says 5 years lifespan on lead acid battery v 15 years on lithium battery? Would that be correct?

unkel

victor8600 wrote: »

If you have a 100Ah battery, then 100Ah x 12V = 1.2KWh

10/1.2 = 8.3, so you would need 9 batteries.

That's literally only the half of it :pac:

You can only use about 50% of the capacity of lead acid, so to have 10kWh usable, you'd have to build a 20kWh lead acid battery. That's exactly what I am doing with 16 * 100Ah AGM batteries

If you can get lead acid batteries for free or really cheap, go for it. And if you do a lithium battery install as part of a heavily subsidised SEAI install, sure go for it too

I wouldn't buy any batteries (lead acid or lithium) new though for home attached storage. It's cheaper to give the electricity away to the grid for free.

physioman

unkel wrote: »

That's literally only the half of it :pac:

You can only use about 50% of the capacity of lead acid, so to have 10kWh usable, you'd have to build a 20kWh lead acid battery. That's exactly what I am doing with 16 * 100Ah AGM batteries

If you can get lead acid batteries for free or really cheap, go for it. And if you do a lithium battery install as part of a heavily subsidised SEAI install, sure go for it too

I wouldn't buy any batteries (lead acid or lithium) new though for home attached storage. It's cheaper to give the electricity away to the grid for free.

How is the battery system working out for you?

unkel

It's not. Not yet.

Waiting for my waterproof cabinet. Once I have it, I can build the battery pack inside it. The inverter and other hardware are already mounted. Once the battery pack is ready, the inverter will be connected to the grid, battery connected to inverter and I should be up and running by then.

murphaph

Do people really give away used lead acid forklift truck batteries in Ireland? I'm at the planning stages for my garage and thinking about at least making provision for a lead acid battery for our planned PV (it may never pay for itself though as we have a 20 year guaranteed FIT here). When I look for used forklift batteries even the defective ones cost a few hundred. I've read that the scrap value is a few hundred for the lead at the moment so you'll never get them for free. Is it different at home?

The "ready to run" batteries make no financial sense here with the FIT and the fact we can raise our self consumption rate by running the heat pump during the daytime and the house is also a home office occupied by my missus all day. That's why I started looking at lead acid but even those look economically unattractive in our use case. Of course if they were free that would change the calculations somewhat lol.

SlowBlowin

physioman wrote: »

Hi has anyone used lead acid batteries for storage. From what I can gather they are obviously cheaper but the life span is 3-5 years. Am very new to this but how many batteries would it take to store 10kwh?

I use lead acid for home electric, I have done so for 8 years.

My cells came with a 20 year warranty, but they were very expensive, and really the only choice available 8 years ago.

You really need to look after them, but if you do they can last a long time, if you miss treat them, even just once or twice, then they are toast...

SlowBlowin

With regard to how much lead acid for storage, I have 4500 Ah @ 12v (theres a reason for 12v and not higher for my needs), this gives me about 10 Kwh of working storage.

unkel

SlowBlowin wrote: »

With regard to how much lead acid for storage, I have 4500 Ah @ 12v (theres a reason for 12v and not higher for my needs), this gives me about 10 Kwh of working storage.

4500/1000 * 12 = 54kWh isn't it?

So you have about 27kWh available. Unless of course you set your minimum voltage level very high?

SlowBlowin

In an ideal world I try to keep the battery at 80% SOC although it often is lower if its cloudy etc...

SlowBlowin

Its also worth noting its much more difficult to "top off" the charge with lead acid (absorption/float charging), lithium ion is much easier. so its rare to have the lead acid at >95% SOC in real world conditions..

10 Kw h is a good "working" guide for everyday use, but you still have to keep and eye on voltage every few hours.

howa .223

I looked at a system already installed on the apartment block in Germany where im staying.( 10 x2 room apartments/glorified bedsits) The Landlord fitted in total a 9kw roof panel system, a 10 kw battery and a hot water diverter for when the system is running at its best.

He knows the system inside out and explained in summer months the system is running efficiently at full out-put 100%, he uses 55% of energy created and sends 45 back to the grid.
In the winter months the system runs 55% of his electric and heating and he takes 45 from the grid, he showed me the app that tracked all the usage and anything sent back to the grid or taken from it.
He is happy with the system but the brand escapes me right now it cost in total 24,000 euro for the panels and 10kw battery storage which can add an additional 7kw of batteries 2 x 3.5kw.
He plans to add more panels and battery storage to full max.

I was impressed with the whole setup he had, BUT... at such a cost with maintenance and eventual losses as the system ages i could not justify the costs of a system like that.

Before anyone should consider a system like that first they should insure the house is as efficient as it can be, LED lighting, zoned heating, as much insulation as possible also draft proof. The older the house sometimes the harder to do, but why spend 10k plus on a system that will just be wasting the energy provided and getting false readings on the systems efficiency.

tech

was at the self build show on Sunday, and got a few prices

2.1 KW system 6 x panels on roof and a divertor €5500 with no grant
4.2 KW system 12 x panels on roof, divertor and 2.6KW battery €13k with on grant

also looked at a Solor Thermo Dymanic panel, €3600 fitted includes compressor and fitting. As I have a Joule twin 300l tank.

unkel

tech wrote: »

was at the self build show on Sunday, and got a few prices

2.1 KW system 6 x panels on roof and a divertor €5500 with no grant
4.2 KW system 12 x panels on roof, divertor and 2.6KW battery €13k with on grant.

Those prices are insane. What was that show called, "Another Irish Rip-off Show"?

tech

I totally agree!!!

solarcity.ie
When you ould get this!!

https://solartricity.ie/grant-kit-2x7-panel-2/

wexfordman2

tech wrote: »

was at the self build show on Sunday, and got a few prices

2.1 KW system 6 x panels on roof and a divertor €5500 with no grant
4.2 KW system 12 x panels on roof, divertor and 2.6KW battery €13k with on grant

also looked at a Solor Thermo Dymanic panel, €3600 fitted includes compressor and fitting. As I have a Joule twin 300l tank.

Wow, that's incredible pricing, I got a 6kwp system with 5kwh battery and diverter for less than that

tech

wexfordman2 wrote: »

Wow, that's incredible pricing, I got a 6kwp system with 5kwh battery and diverter for less than that

Hi can you post details of suppiler, did u diy install tks

Clarelassie

It is worth checking around on pricing. SaveMeMoney are very competitive on pricing and can help with the grant applications - https://www.savememoney.ie/

unkel

Clarelassie wrote: »

It is worth checking around on pricing. SaveMeMoney are very competitive on pricing and can help with the grant applications - https://www.savememoney.ie/

They gave me a quote too which was very competitive. I am very aware of what the trade pays for materials like panels, inverters and batteries, and he wasn't overcharging me at all, just a small markup. And the owner knows his stuff and is really helpful. Also one of only a handful of the SEAI companies that I contacted that came back with some meaningful replies (my setup wasn't a regular install)

Ubbquittious

unkel wrote: »

Those prices are insane. What was that show called, "Another Irish Rip-off Show"?

That's how these things always go in Ireland. Nobody wants to do any real work and they're all looking for easy money, hoping to jump on the next bandwagon. You'll have a couple of chancers who'll don their suits and ties and lay on the "moving the goalposts" and "revert back to you" talk after taking a 2 day crash course on how to connect the two wires from a solar array to an inverter. They'll phone up a few suppliers for all the goodies they need from Shenzhen and next thing you'll see them at all these shows.

The remainder of the time they'll be chasing grants and finding ways to become eligible to take more grants and do government tenders. Don't ask these fellas anything technical because they know fcuk all and the polish fella they didn't bring with them on the day is the only one who actually knows how to mount them onto the roof.

You'll see these lads at every chamber of commerce meeting and politicians' clinic bigging themselves up and trying to rub shoulders with the perceived 'big boys'. They probably come across as fierce friendly and jovial fellas altogether .. until you get to know them

phester28

And then they are employed by the big Electricity suppliers to install Green energy on their behalf as they will be SEAI approved.