Solar PV battery options

the_amazing_raisin · 20-09-2022 3:57pm

https://www.boards.ie/discussion/comment/119641147#Comment_119641147

One thing I noticed about OYE is that a lot of their ratings seem to be those one liner, 5 star reviews that are characteristic of bots

Even the ones with pictures look a bit dicey, almost look like the same package from a bunch of different angles

I know there's only so many ways a generic box with identical blue cells inside can look, but still...

PWOD also have a fair number of bot reviews, but there's also a good number of more detailed write-ups that look more realistic. Almost like there was a human in the chair 🤔

So while I don't fully trust the reviews of either, it does look like PWOD gets some better reviews overall

That's not to say that OYE are junk, or that PWOD are automatically good. Just something to consider I would say...

aleesi · 20-09-2022 4:46pm

https://www.boards.ie/discussion/comment/119634441#Comment_119634441

I pinged them a few weeks back over email and they gave me the datasheets I was requesting. Their sales team contacted me via whatsapp and told me they can source the pack and also the batteries as long as it is disassembled (unfinished product). They game me 2 prices for the 135Ah and 280Ah kits which as you mentioned should include everything (BMS cables and other bits and pieces) as well as the batteries. The prices are for both EU based warehouse and directly from china (€1,850 for the 135Ah from china or €2,200 from EU both door to door).

I'm really tempted to go for them, apparently they are very popular in the S. African and Australian markets. They are not much more expensive than buying everything separate but much less of a hustle if they provide all you need in the same box...

I've been quoted 2,800 for a second puredrive... f t sh*t ... With that money I can add a second inverter / charger to the system with another battery ...

yankinlk · 20-09-2022 5:09pm

https://www.boards.ie/discussion/comment/119642654#Comment_119642654

is that 1850/2200 for 10KWh batteries inlduing all the kit parts needed? anything else needed to buy to get up and running?

connesha · 20-09-2022 6:26pm

https://www.boards.ie/discussion/comment/119537673#Comment_119537673

Did you hear any more from Solis on this 100A->75A->100A->75A @SD_DRACULA ?

SD_DRACULA · 20-09-2022 8:31pm

https://www.boards.ie/discussion/comment/119643031#Comment_119643031

Not yet, I am sort of reluctant to tell them to update the FW in case they break who knows what else.

aleesi · 20-09-2022 10:38pm

https://www.boards.ie/discussion/comment/119642734#Comment_119642734

Prices are for the 135Ah (135Ah times 48V = 6,480Kwh from China or EU warehouse door 2 door including everything you need to assemble the battery. I guess their case alone is a few quid so buying thing separate (without the case) will be cheaper but still this option works out at €250 per KWh thats pretty much half price when compared with a puredrive

yankinlk · 21-09-2022 7:24am

https://www.boards.ie/discussion/comment/119644156#Comment_119644156

Thanks.

Ouch. The math doesn't work for me at that costing. I like the idea of a kit that would be easier for me to follow, the video was great but ... just not worth it until prices come down imho.

aleesi · 21-09-2022 11:17am

https://www.boards.ie/discussion/comment/119644712#Comment_119644712

I would agree however even buying batteries and bms separate, either I'm not looking in the right place or just the batteries alone from the aliexpress shops everyone is mentioning here are not substantially cheaper. Oye store has the 200Ah (roughly 10KWh) for 1,600 (no VAT) on top of that you need the BMS 200 and cables and bit and bobs 100 and you'd need to build your own case. I think I may just go for the mason + batteries. The off-grid garage due is been really helpful, I think I'm going to bite the bullet...

Does anyone has the the DIY pack in the attic? any concerns re/ fire or leakage? I could accommodate in the utility room or shed but attic would be straight forward as I have a hybrid inverter in place.

unkel · 21-09-2022 12:00pm

As long as you are certain your battery chemistry is LiFePO4, you can store them in your house / attic. Any other chemistry (like Tesla Powerwall) and they must not be installed inside your house at all. That said, my DIY powerwall is LiFePO4 and I have it installed in an outdoor steel cabinet surrounded by 3 stone walls. I also have all my inverters installed on the outside of my house mounted on stone walls.

Whatever you do, your hybrid inverter must be right beside the battery (recommended max cable length 2m) as because the relatively low voltage of the battery, your losses would be horrendous with longer cables.

Mr Q · 21-09-2022 1:38pm

https://www.boards.ie/discussion/comment/119637007#Comment_119637007

Nice, where did you buy the EVE cells from?

the_amazing_raisin · 21-09-2022 4:20pm

https://www.boards.ie/discussion/comment/119645631#Comment_119645631

I totally misread that and thought you had 3 layers of walls around the cabinet

Fortified battery bank 🤣

ELM327 · 21-09-2022 4:39pm

https://www.boards.ie/discussion/comment/119645631#Comment_119645631

Where is that guidance from?

I have some old 12v lead acid truck batteries I got for free and am thinking of how best to implement them into my system. I was planning to have them in my office kitchen with the inverter.

unkel · 21-09-2022 4:51pm

Lead acid is generally ok in a ventilated room. Not sure how you could fit them into your system, but if you have a garage, shed, barn or any outbuilding really, you could setup a wee off grid system in there for your lights, power tools, etc. Would be a good way to play around with it yourself a bit, without having to spend a fortune on parts. One PV panel and a cheap solar charge controller will do the trick

Shameless plug for a 30A cheap solar charge controller 😁

https://www.adverts.ie/campers-motorhomes/solar-charge-controller/27825303

Sligobuck · 21-09-2022 6:21pm

https://www.boards.ie/discussion/comment/119646078#Comment_119646078

OYE so fingers crossed, do not count on any power out parties until I get through deliveries and quality risks 🤞🤔

the_amazing_raisin · 21-09-2022 7:16pm

https://www.boards.ie/discussion/comment/119647074#Comment_119647074

What about a couple of solar panels on a shed charging the batteries? And then use an inverter to power the lawnmower and other tools

ELM327 · 22-09-2022 10:00am

Yes that's pretty close to the intention. I have about 2kWp of solar panels coming in the next day or two, partially aimed at tackling the gap in production in the evening (ie the west), and partly will be to connect to my 12v batteries charge them up and use that stored energy when possible. I have 3 inverters coming too. They were the ones suggested by the "prowze" guy on youtube

graememk · 22-09-2022 10:23am

https://www.boards.ie/discussion/comment/119649436#Comment_119649436

Have a play with the jrc website.

It seems like pure west facing panels generate more power in total the lower the angle, eg 15 degrees.

It doesnt really effect the winter production much. Just boosts summer production.

But, What it doesnt tell you, the flatter the panel, is catching more mid day sun, If your looking to fill a gap in the evening, Id try and angle them steeper, to get the evening sun, as you could have more than you actually need at mid day.

ELM327 · 22-09-2022 11:14am

Yup I was looking around and since the gap is 3-4pm onwards, I think steep panels on a mount facing due west on the top of my pumphouse will do nicely.

I'm maxing out the inverter (not today of course in the downpour here in enniscorthy) usually for about 3-4 hours around midday so any excess would likely be wasted and sent to the grid.

unkel · 22-09-2022 12:13pm

Sending to the grid is very lucrative if you get paid €0.14 / kWh for it, "waste" is the wrong word!!!

If I had huge roof space (farm with large barn or something similar), I'd invest in a setup purely for export.

ELM327 · 22-09-2022 12:20pm

https://www.boards.ie/discussion/comment/119650084#Comment_119650084

I'll never have a smart meter so I will never get paid for actual exports.

Of course, if I'm ever forced onto one and it's before I'm off grid, then I will be exporting to the grid any excess but as it stands now I'd rather use the energy to burn a space heater than give it to networks for free

Down the road, if smart meter plans become reasonable and I decide to get one, I'll go for an NC7 and really start exporting a lot. I think this could be a better use of funds than 100% off grid, as with nc6 you're limited to 6kW export. However it relies on smart meter plans becoming reasonable.

Mr Q · 22-09-2022 12:50pm

https://www.boards.ie/discussion/comment/119650084#Comment_119650084

That makes sense. But there are no guarantees they will still be paying that in 12 or 24 months for each kWh.

the_amazing_raisin · 23-09-2022 9:20pm

https://www.boards.ie/discussion/comment/119650247#Comment_119650247

If you're above 6kWp (at this point ELM probably is) then you can go onto the CEP rate by sending the NC7 form

That gives you a fixed rate of 13.5c, and I think it's guaranteed for something like 15 years

Not sure if they'll give you deemed export at that rate or if they'll just tell you to f**k off and get a smart meter

AidenL · 23-09-2022 9:34pm

I installed two more 3.6kwh Pylontechs today for a total,of 14.4kwh storage.

I intend to feed the newly installed heat pump with night rate from Energia over the winter.

SD_DRACULA · 24-09-2022 2:12pm

https://www.boards.ie/discussion/comment/119657350#Comment_119657350

This is when you hope your heat pump doesn't pull more than 3.5kwh or you will also pull from the grid after exactly 15 mins - if using battery and pump but if only using it at night won't matter

the_amazing_raisin · 24-09-2022 4:24pm

https://www.boards.ie/discussion/comment/119659307#Comment_119659307

To be fair I don't think my 6kW output heat pump pulls more than 800W most of the time. It seems to go for the slow and steady approach

It's when the auxiliary heater kicks in that you see the power consumption go way up. Hopefully that's only about 10% of the time in winter, and mostly at night when it's extra cold

micks_address · 25-09-2022 9:46am

Question on how to size a battery for your installation. Two installers have suggested 5kw is big enough.. others say go bigger around 8kw...we use around 500kw per month.. I'm tempted to go with the larger size as once and done.. looking at 6.5kw solar panels

AidenL · 25-09-2022 10:05am

https://www.boards.ie/discussion/comment/119659307#Comment_119659307

An yeah, I know it won’t take care of every situation, but I think it will be a big help. Hopefully!

AidenL · 25-09-2022 10:07am

https://www.boards.ie/discussion/comment/119659700#Comment_119659700

I’d say the same from watching loads so far, admittedly it’s not too cold yet.

And the leigeonella cycle will be covered at night rate costs anyway.

I don’t expect any immersion involvement in normal heating or hot water generation as the heat pump is well sized, plus it’s a Panasonic TCap, so the immersion will only come on bar the leigeonela function, below minus 20.

the_amazing_raisin · 25-09-2022 10:11am

There's no real one size fits all answer, but there's a few things you can look at

First I'd be thinking about what your objectives for your system are. If you're hoping purely to save money then probably go for the smallest battery that you can get away with, enough to get you through the evening time until the night rates kick in

You're right to look at consumption, personally I want a battery to cover one days consumption in winter, so I looked at the average daily consumption in December/January and that gave me a battery size of 20kWh

Also, you've an EV right? If so then don't count the EV consumption when figuring out the required battery size. You'll end up with way too much power and there's no logic in discharging your battery to the EV except in an emergency

Unfortunately batteries are pretty expensive so you need to balance this against your budget. In general a bigger battery should allow you to self consume more, or shift consumption to night rates

If you're looking to go off grid, or keep your power on during an extended power cut then you'll probably need a bigger battery, not only for extra capacity, but also because you can only discharge so much power from a battery at one time.

You'll want to ensure the kWh of the battery is equal or greater than any critical loads you'll want during a power cut. A 5kWh battery for example can generally supply 5kW continuously, although it's often better to go for half of this

If you're powering just a few lights and maybe charging phones during a power cut then you'll be fine with a small battery. If you need to do some cooking or heating then you'll probably need more

micks_address · 25-09-2022 11:02am

Thanks yes have an EV.. the quote I have at the moment includes an 8.2kw givenergy battery.. seems keen enough.. probably going to book the install tomorrow.. 6.2kw solar panels (16) and givenergy invertor.. not going with eddi yet..

Solar PV battery options

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