Solar PV battery options

DrPhilG

It's a 20kWh pack and I'm using 80% of it so about 16kWh.

The BMS and inverter are using the same settings as the PylonTech were, so 20-100% I think.

Haven't looked at changing that yet.

slave1

Question if I may, through the magic of whatever controls you have can you prioritise where your PV goes.

Obviously house first but I'd like to have the EDDI take first in the list after house as showers are early in the day, then surplus can go to battery.

Is this possible?

Well done again, I'm sure you were sweating it with long wait and then us randomers telling you it will arrive to keep the spirits up

championc

https://www.boards.ie/discussion/comment/117715426#Comment_117715426

You can only prioritize an Eddi over battery charging if you have an AC Connected Storage Inverter like a Tesla Powerwall or a Sofar ME3000.

With hybrid units, the power stays within the unit, so it's never seen until the battery is at 100%.

It my be possible to fudge it by setting a low charge rate in a hybrid, which would mean that, with a large array, you could be charging the batteries while also feeding an Eddi.

slave1

I'd be going non hybrid and Sofar route so good to know Sofar caters for "selection" of where surplus goes.

Would be great if MyEnergi got their app with battery monitoring up and running as it's so easy to prioritize between EDDI and Zappi by just dragging an icon on the App

insular1

https://www.boards.ie/discussion/comment/117715630#Comment_117715630

Forgive me if this has already been answered but does the sofar ME3000 get rid of the need for a hybrid inverter?

I already have the solar set up and next year or so will be looking at going DIY battery route like DrPhil unless there is a serious FIT. I have a weird set up split across 2 roofs with one roof using microinverters and the other using a solis inverter. I thought I'd need to replace the Solis with a hybrid inverter in order to install the batteries but was at a loss as to how I could get the excess from the microinverters into the batteries.

Would using the ME3000 instead sort this issue for me or would I still need a hybrid inverter?

SD_DRACULA

Just gone through this thread from start to finish to brush up on my lifepo4 knowledge and all pics/attachements prior to page 24 are gone.

Thanks for that Boards 🙄

Nice migration.

championc

@insular1 can you combine the AC side of both of those installs ? If so, then the Sofar is perfect in that it can then measure the total solar output

irishchris

Should work in that I have a non hybrid system on roof and hybrid ground mounted one. The hybrid CT clamp reads any excess going to grid and sends all of that power to the battery. So at times the power going to charge my battery is greater than what the hybrid is producing.

graememk

So the likes of the sofar me3000sp is a stand alone storage inverter.

It has 2 ct inputs one on the main feed from the grid and one on the solar (although I think it would work without the solar ct, but any stats from it would be useless)

It's connected into the consumer unit the same way as a solar inverter.

It monitors the grid import/export and charges when it sees export and discharged when it sees import.

The eddi would need a ct on the me3000sp feed to be able to "see" it.

It needs about 100w of export to come out of standby in the morning but when running it's spot on "keeps balance"

Would really recommend a bms that can communicate - it just makes life easier.

The latest firmware added support for LG batteries - which use the SMA protocol.

I've heard the Seplos BMS works (uses the SMA protocol).

DrPhilG

Forecast for today and tomorrow was absolute muck. Heavy cloud and rain all day.

So last night I charged the battery to 75% on night rate.

Currently at 88% with the sun splitting the stones.

So despite having a 20kWh battery I will most likely end up exporting today!

Don't even have an EV any more to plug in.

slave1

Throw some of that weather my way please

DrPhilG

Think I might have.

An hour ago we were generating 4kw, now 525w lol.

insular1

https://www.boards.ie/discussion/comment/117718025#Comment_117718025

I should be able to as both feed into the main fuse board. But if I couldn't then based on what graememk said above I could just set the me3000 to detect any export on the mains and send it directly to the batteries? So let say I could only hook the inverter up to the me3000 and not the microinverters once the me3000 detects any export, even if it's from the microinverters, it could still send this to the batteries?

championc

https://www.boards.ie/discussion/comment/117719859#Comment_117719859

Don't think of "hooking it up to" anything. It's a standalone inverter which ultimately will stop power going out to the grid, and will charge the batteries with it

graememk

https://www.boards.ie/discussion/comment/117719859#Comment_117719859

To get the solar output both wires can be passed through the CT.

I've ran the sofar without the solar input, before I had solar installed. (Was waiting for better weather for the solar install)

I'm almost sure it will work without the solar CT. And if your getting closer I'll check for you sometime.

insular1

Thanks for the responses. This has been a brilliant thread. I've a bit of time to research more anyway but will almost certainly be back with more questions! It's great to see people going the DIY route and have it work out well. Gives me a bit of confidence.

DrPhilG

Well if you're planning a DIY using the ZEVA BMS, better move fast. They're winding up.

From ZEVA...

Important Notice: ZEVA products are going "open source"

-Ian Hooper, 6 August 2021

Last month I announced I would be winding down ZEVA in order to pursue other opportunities, with new orders accepted until the end of September 2021. After much community feedback and concern about ongoing availability of products, I have decided to "open source" the designs of all ZEVA products. This means that you will soon be able to download everything needed to reproduce each product, both pre-prepared production files and code/schematic/PCB files in case you wish to modify/add functionality.

All files will be provided freely to use for any purpose (including resale) and may be freely modified, but use is entirely at your own risk and without any support or warranty, including implied warranty of merchantability or fitness for a particular purpose.

Unless you're the sort of person who particularly enjoys the challenge of building new things, it probably won't be worth the time and effort of figuring out how to assemble each device yourself, but it is my hope that various individuals and businesses around the world will soon start reproducing the designs for resale in their region, and I plan to maintain a list of resellers on this website.

For the sake of a smooth transition, products will continue to be available here for the next couple of months, with 10% off all orders while stocks last. All products manufactured here will come with 12 months warranty and tech support. All product information, manuals and the contact form will continue to be available here indefinitely.

graememk

Ah good, Glad its going open source.

JLCPCB do a pcb and assembly service - no idea on cost there though (or availability of parts). But at least the option is there for the community.

Ian was able to provide a custom firmware for mine, as the sofar didnt like having both the pylontech and SMA protocols running at the same time (weird ,random charging events)

Another option is the Seplos (no experience there, but I know of at least 1 person on the sofar automation fb page that has one and is waiting on batteries to arrive).

I'm starting to build a device on a ESP32 board and a CAN breakout board to pull battery data straight from the BMS - for my own curiosity and the SMA protocol isn't that complicated - once I got my head around how it worked.

REC-BMS is another bms that would be another compatible one.

DrPhilG

Yeah I looked into REC earlier in the process but the support and communication from Ian at ZEVA swung it.

irishchris

Well the endless cycle of me giving Esb networks many hundreds of free KW and then paying them for the same this back every night had finally been broken. Added two 4.8 KW batteries to my existing 2.4kw battery which I bought this week (cheers again Phil). Made it all worthwhile this morning to get up

Screenshot_2021-08-09-11-38-45-353_com.ginlong.home.jpg

and see how much energy I bought from esb 😀

MAULBROOK

https://www.boards.ie/discussion/comment/117727339#Comment_117727339

Come on, try harder 😅😅

Geeyfds53573

https://www.boards.ie/discussion/comment/117692617#Comment_117692617

Finally caught up on this thread was dying to see the final result and knew DrPhilG would include pics - Very well done DrPhilG maybe a change of career on the cards? Thanks to all others for their contributions I feel confident I could do this. I don’t think battery prices are going down as quickly as I thought they would.

garo

https://www.boards.ie/discussion/comment/117735247#Comment_117735247

They've actually gone up. Te price on Aliexpress is now close to 2000 from a shade under 1400 when DrPhil got his.

SD_DRACULA

https://www.boards.ie/discussion/comment/117735283#Comment_117735283

Yup have gone waaay up instead, lithium is in high demand due to EV ramp up and pushing up the prices.

graememk

https://www.boards.ie/discussion/comment/117736390#Comment_117736390

Its far more likely shipping costs that have gone through the roof.

Ive been watching the 320ah prismatic CATL cells and they havent really gone up much more in cost. - apparently there is EU Stock of them too. 2.6kish -15.8kwh. - 3-5 day delivery apparently...

Price of cells are going down, but shipping costs are rocketing.

unkel

Cost of a 40' shipping container from China to Ireland has gone from $4k to $11k in a year...

championc

Is anyone is interested in the Seplos BMS, I will buy several and sell at €220 each including delivery to EU countries only (sorry, I'm not getting involved in NI or UK exporting)

The Seplos will connect to a DIY 15s or 16s cell pack and emulate a Pylontech battery. It has a CANBUS and RS485 port, and it's own LCD screen

PM me for pre-orders

graememk

https://www.boards.ie/discussion/comment/117737593#Comment_117737593

NI should be fine, as it is still technically in the EU.. or they could come down and collect it!

garo

https://www.boards.ie/discussion/comment/117737593#Comment_117737593

How does the Seplos compare to Zeva and other BMSes. I might hop on even though I don't have a battery yet. Planning on getting one when prices come down slightly.

championc

Certainly the Seplos will also allow you to daisy chain two separate banks in parallel. With the RS485 interface, I hope to pull my individual cell details into my Node-Red Dashboard. And finally, the Seplos is cheaper than the Zeva and the Zeva is basically shut down as a product.