Solar PV battery options

bullit_dodger

https://www.boards.ie/discussion/comment/118184666#Comment_118184666

With my OWL? No. It's only got 1x CT clamp, so it can only measure one spot. I have my one setup on the GRID live in since before I got my solar installation in.....so now it gives odd readings as it only knows one part of the equation. For example, if the sun is up and the panels are generating 500w and the house is using 1200w, the OWL will say I'm using 700W as it only sees the grid import.

However, there are OWL versions which do have multiple CT clamps.

I also (arrived yesterday) bought for my Dad

Efergy Technologies Engage HUB 1.1 in-Home Energy Monitor : Amazon.co.uk: DIY & Tools

That does also support 3x CT clamps, though I only got one CT clamp. It's pretty good too. Has a web interface, as opposed to a seperate digital device.....so you have to use your phone or some other thing to read the values, but yeah.....decent enough. Probably slightly recommend the efergy, but again the OWL has served me well for many a year.

47akak

https://www.boards.ie/discussion/comment/118183016#Comment_118183016

A crashed Leaf, don't know want to say much more, wasn't trying to rip anyone off just saw one and asked and guy said yeah, he had a vague idea of their utility and value but I got the impression it was more of a "just get rid of it" type thing. They weren't quite free but very low cost per kWh, if I can even get 5kWh worth of cells out of the pack it's fair value for me

graememk

https://www.boards.ie/discussion/comment/118185102#Comment_118185102

I have an old OWL (completely wireless) and It cant handle low usage at all, as it doesnt have a voltage reference. I could be drawing nothing from the grid, but it will still say 200 odd watts. Also doesnt read correctly if there's any large induction loads happening too (motors) or if the car is charging from solar.

To measure Solar and household usage needs to have a voltage reference for any sort of accurate measurement.

slave1

https://www.boards.ie/discussion/comment/118184603#Comment_118184603

I didn't know those places were still in business, PM and AddressPal closed up.

So you'd pay full UK VAT and then nothing more after that apart from deliverme fee?

the_amazing_raisin

https://www.boards.ie/discussion/comment/118185572#Comment_118185572

I've got one of the open energy monitors (I'm not affiliated, just giving my opinion 😀)

https://guide.openenergymonitor.org/applications/home-energy/

They're a little pricey compared to the OWL, and you might need 2 parts, the monitor and the base

But they can handle 4 CT clamps, so for me that was giving Home, heat pump, immersion and EV charger. Plus they have an AC supply so it gives accurate readings. It also logs the data locally, so you're not relying on some cloud service which the vendor might get bored of

I had to take it down about a year ago because we repainted and the wife didn't like the mess of wires coming from the fuse box. I'm hoping to get a socket installed nearby so I can put the whole thing into it's own enclosure and make it neat

graememk

https://www.boards.ie/discussion/comment/118185576#Comment_118185576

Looks like it, I know theres one like that near Muff (just over the border tho), where you can do pickups too.

Id do it sooner rather than later though, you'd never know if/when boris pulls the article 16 lever.

(oh they are in newry.. Wouldnt take long to take a spin up there )

the_amazing_raisin

Apologies if there's already a thread for this, but I'm wondering if anyone has any experience of Pylontech batteries? I was all set for building my own battery from Winston cells, but the Pylontech looks to be not much more expensive, and I like how modular the system is. If one battery fails I can take it out and it's easy to expand later when the magic money tree bears fruit 😁

I did see this video recently about a guy in the UK having some issues with getting one repaired under warranty

https://www.youtube.com/watch?v=3ret0QH1Gqg

I think some of his points about the firmware not being updated weren't exactly valid, they're just going to send him whatever is on the shelf, not handcraft each battery

But his point about the battery going for repair made me pause. I don't have a problem with it being repaired, I can understand that with it being a valuable product they'd prefer to repair, but I'd be concered about the unit getting shipped off for months while I'm down a module and ~€800

Does anyone know if there's anyone in Ireland who does service & repair on Pylontech products? I've so far found one crowd in Dublin who sell them, but no idea if they do reapair or will be sending it off elsewhere

reklamos

https://www.boards.ie/discussion/comment/118185684#Comment_118185684

I do not think anyone would repair them locally. At best they would replace the unit with other used/refurbished, otherwise they would send them to manufacture. I have 3 of them and thankfully they are working fine so far. I have not done firmware updates but I do know there is a need to do that if you mix older(non-c) with newer(C) units.

Mr Q

I know that most of the DIY batteries here are 48v. But does anyone know of a BMS that could connect to a SMA SBS (Sunny Boy Storage) 2.5 AC coupled charger. This is not the same as the SMA Sunny Island I have seen mentioned somewhere here. It is designed for high voltage batteries.

Or some type of device that could connect to the SBS and then talk directly to the HV battery from something like an Outlander or Leaf as an example.

the_amazing_raisin

https://www.boards.ie/discussion/comment/118185853#Comment_118185853

Yeah they do seem reliable based on reports, and one of the things I like is that if there's a fault then you're only out 1 module instead of a full battery. I think the guy above just had some bad luck

He did mention that Pylontech only do repairs, not replacements unless it's a total loss. It makes sense since they're valuable pieces of hardware, and they also lose value once they've cycles on them, so resale of repaired stock would be at a penalty to them

It could also be BS that he heard from the vendor, since batteries are in high demand at the moment and they tend to be on back order they probably don't have enough sitting around that they can just swap him a replacement battery

It looks like the crowd in Dublin are about €100 more expensive than the cheapest I've found in the UK. It might be worth going with them since if something goes wrong I'd be able to drop it round to them instead of paying postage to the UK.

boarduser01

https://www.boards.ie/discussion/comment/118095583#Comment_118095583

The inverter is a PrimeHybridEngergy one, and the associated two PrimeEnergy 2.5kw batteries. I am guessing it is only going to work with their own batteries.

I have the old "Delta Model RPI H5A" Inverter still too, that was installed initially with the solar panels before the Hybrid inverter and batteries were installed.

I really hope that I can find a better setup, with at least 10kw battery storage that can be used with shifting night load too.

graememk

https://www.boards.ie/discussion/comment/118187247#Comment_118187247

I've heard of them. But can't help you whether you can diy a battery or not unfortunately and can't really see if they use any common protocols or not.

mustang68

Hi Folks (I'm sorry

Got some very basic battery questions, sorry if it's been answered already here but there are a lot of posts to sift through:

I had been looking for a 2.5kw battery (for load optimization for my upcoming solar panels), a PylonTech seems to run about 1200 cost, my understanding is that I can get a few cells like this from AliExpress giving say 4 giving me 3.6kwh for 660€, a BMS, busbars connectors and enclosure and I'm good to go, correct?

It seems that there may be some value in getting a larger battery and charging it using a night rate, are people doing this, is it saving money?

Thanks

graememk

https://www.boards.ie/discussion/comment/118190819#Comment_118190819

you need at least 16 to supply the 48V

(actually you can get away with 15, but 16 is preferable)

bullit_dodger

https://www.boards.ie/discussion/comment/118190819#Comment_118190819

Just to answer your last question there....

It seems that there may be some value in getting a larger battery and charging it using a night rate, are people doing this, is it saving money?

Short answer is "yes". Longer answer is like many things to do with batteries...."It depends on your consumption".

If you do a thought experiment, and setup a fictional house with 20Kwhr battery, but you only use 10Kwhr/day. So you charge the battery on the 1st night, but of course the fact that you only use 10KwHr/day means that you won't completely deplete the battery before you get another opportunity to charge it again the following night. I'll ignore the fact that some of that 10Kwhr that you are using would be at night rate also, so you'd take that directly from the grid rather than the battery.

So in this experiment had you bought a 10Kwhr battery (for cheaper money), you could achieve the same savings daily, and ultimately payback your battery quicker. So consumption matters. You need to size the battery to your needs and not over engineer it.

That said, (leaving your question aside about the night rate) there is value in a bigger battery in summertime where you might store up energy on a sunny day and then use it in your home the following day where it's cloudy and your not generating much - but that's a different question, and probably not something to easily model.

unkel

I have a large electricity consumption and as soon as I have the 20kWh setup, I will charge it in full every night during winter and I will use all those kWh the next day at peak rates, no matter how sunny the day is. So yeah, that pays significantly towards the cost of the battery. Also in summer when the battery is fully charged after the end of a sunny day, I will use all of that at peak rates and it will be empty by the time night rate kicks in

For most people (with a much smaller electricity consumption), this doesn't hold of course and the savings with the battery are minimal

bullit_dodger

You and me unkel are somewhat special cases. :-)

it's easy to cycle a 8Kwhr battery when you are using 30Kw+ / day. Damm thing was empty by 4pm there yesterday.....

mrm

https://www.boards.ie/discussion/comment/118191353#Comment_118191353

So unkel regarding the savings even for national average consumption values, as a lot of families return to the house in the evening (after work/ school) at the time when solar generation has probably finished for that day I would reckon that the battery 'essential' for taking a full charge during the day for household use over the evening. If a battery is not included within the system are people simply purchasing a PV array/ inverter that they cannot fully benefit from (through use at solar generation time). Or have I got this completely wrong?

Payback seems to be out of reach no matter which way you go:

• PV array with battery - costly but maximises use of power generation inhouse
• PV array with no battery - cannot maximise return (and potentially most goes to grid)

SD_DRACULA

If you have people at home 24/7 you would be able to do things like cooking/washing/etc during the solar gen so you might get away without battery if not, then when you get home and even if a 5kwh battery is full from solar, you will fly through it (unless you don't have an electric hob/oven) and just watch TV.

bullit_dodger

mrm - I'd tend to agree with you there. I think to properly utilize an array, you have to have a storage mechanism of "some type". A battery is the obvious choice. A good Feed-in-Tariff would be another way, ideally one where you had a 1:1 mapping of what you exported to what you bought back, but while I might seem negative - I can't see it EVER in Ireland IMHO. Lastly heating the water in an immersion via EDDI/iBoost, assuming you use that hot water energy in the evening when you get home would also work, although there are many disadvantages there with the hot water idea (losses etc)

In terms of payback in general though on installation, I'd be fairly optimistic. A lot of this depends VERY MUCH on what you paid for initially and that you didn't get gouged, but I think ~10 years is a realistic and achievable target for everyone. The way I like to think about it is that I'm paying a whopping big bill now and have vastly reduced bills going forth.

Bobeagleburger

The way prices are going with electricty pay back will be much quicker than expected. Provided you don't overpay for initial install obviously!

I wouldn't get caught up in payback time once you're happy with it, and have paid a reasonable price. Think of minimal bills half the year, reduced bills the other half, and plus you're doing your bit for the environment.

Bobeagleburger

https://www.boards.ie/discussion/comment/118191592#Comment_118191592

10 years is without a doubt realistic and probably less tbh.

unkel

Very, very optimistic, unless electricity prices are going to drastically increase over the next few years. 10 years even on a DIY system if you bought the parts with trade discount is on the optimistic side...

DrPhilG

I've been adding about 10kWh a night and haven't run out before night rate as yet.

Usually get there with about 35% left so start the next day in the mid 80s.

Bobeagleburger

https://www.boards.ie/discussion/comment/118192256#Comment_118192256

I dunno, I got a decent price on a 5.7kWp system. On a ok 24 hr unit rate. Solar was providing 90+% units during the summer. 70/50/40% the last 3 months. Still at 76% unit coverage overall since May.

Need a full year at it to really make some calculations but the signs are good.

unkel

You said it was without a doubt realistic. How much did you pay in total after subsidy? Divide that by 10 and that's your saving you need to make per year if you want it to pay back in 10 years (in simple terms, disregarding cost of finance or opportunity costs of money)

Is that figure realistic? Did you try do a few sums showing savings of something ballpark of that figure? You are new to this, I can see how / why you want to be optimistic, but from now on until spring, there is very little saving from PV. Even if you load up your battery at night with cheap night rate. Also the FIT will add considerably to the pay back time...

Bobeagleburger

https://www.boards.ie/discussion/comment/118192382#Comment_118192382

A bit shy of 4500. I'd be optimistic of making 450 savings per year.

unkel

Very good price for a battery system. Any details of the spec?

Bobeagleburger

https://www.boards.ie/discussion/comment/118192439#Comment_118192439

Thats my overall system unkel. Only have a 2.4 battery. Going to do the maths after the winter to see if adding more makes sense for me. As I said I need a full year of data. Jealous of some of the battery systems I see in here!

mrm

https://www.boards.ie/discussion/comment/118192353#Comment_118192353

Do you have a battery 6? Eddi?

Even on those percentages my paper estimates still struggle to see anything close to a 10 year payback - it seems hugely optimistic, but prices are only going to rise so that will accelerate it. Anything needing replacing within the 10 years (if the warranty is not sufficient) blows that payback figure out of the water. I need to get my head around how much the payback vs environmental consideration (ignoring embodied energy) aspect will determine my decision - the EV is starting to look the better option I think. I do like the idea of running the home on solar as much as possible though - comforting somewhat.

What is the general replacement time for the various items - batteries; eddi; inverter?

Edit: sorry, I see you answered the battery question during my slow typing.