Is a device like this available?

Tozz

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Hi all!

I've been looking at some grid-tied home storage system for some time to maximize self-consumption. I would love a Tesla Powerwall, but they are not available in Europe yet and they do not have 3-phase inverters. For Europe they seem to rely on a SolarEdge inverter. Anyway, not available. There is SolarEdge's StorEdge, but that also only works with single phase inverters. I also have 2 separate PV arrays from 2 brands (Growatt and SolarEdge), which adds to the complexity.

To clarify: I'm from Europe and I have 240V 3-phase at home (50 Hz).

I would like to build a stand-alone system (not connected to my PV arrays) that:

- Has some kind of input on which i can tell the device how much to charge or discharge (eg. TCP, HTTP, rs232, RS485, does not really matter). So I would like to be able to send:
'charge at 500W', 'charge at 2000W' or 'Discharge at 750W'. In this way I can charge when I have excess solar and discharge for example at night.
I already have all the equipment running to determine how much excess power I have or how much power I draw from the grid.
- Can charge my battery bank from AC
- Can feed AC power from the battery, grid-tied.
- Ideally 3-phase inverter, but 1-phase will also do (i can use 3 inverter/chargers if I wanted, 1 per phase)
- AC input and output should be around 3 to 5 kW (my PV generates about 5 kW during peak hours, but 3 kW is also good so I can use common 16A breaker)


- I do not need any type of backup power. I want everything grid-tied.

I have been Googleing extensively but cannot find anything that comes close.

I have looked at both SMA Sunny Island and Outback Power FXR, but both seem to work on the principle that all loads are connected to the inverter, and that the inverter is the only device connected to the grid. This will not work for me. Besides both devices cannot supply enough current to charge my EV. Outback is limited to 10 amps for example.


Does such a device exists?
 
I did lots of research and ended with the victron multigrid which can be used in parallel.

The infini 10kW would be perfect but is supposed to have a standby consumption of 200W which adds up dramatically.

Rest of hybrid inverters is not capable of managing 3 phase and control zero draw from grid...

In Austria you have to go on 3 phases when you exceed 3 kW per phase.

Regards
Karl
 
Charly144 said:
I did lots of research and ended with the victron multigrid which can be used in parallel.
The infini 10kW would be perfect but is supposed to have a standby consumption of 200W which adds up dramatically.
Rest of hybrid inverters is not capable of managing 3 phase and control zero draw from grid...

Thanks! I've Googled the Infini, and indeed.. They seem to have some pretty high standby consumption, so I'll skip that one.

I'm looking at the Victron Multigrid. Looks interesting! It's not clear to me yet how I can control the charge/discharge rate with the Victron

3-phase is not a hard requirement. If there is a good 1-phase option I'm open to that as well, I could just hook 3 of those to the battery and fix all 3 phases like that.
 
It controls charge/discharge automatically via reading out a smartmeter on the grid connection and tries to balance consumption to zero...
No need to do something externally.

I will add an Eltek Smartpack for higher charging current in order to fully utilize my pv production. It will be controlled by batrium and a little external logic.

Best
Karl
 
Charly144 said:
I did lots of research and ended with the victron multigrid which can be used in parallel.

The infini 10kW would be perfect but is supposed to have a standby consumption of 200W which adds up dramatically.

Rest of hybrid inverters is not capable of managing 3 phase and control zero draw from grid...

In Austria you have to go on 3 phases when you exceed 3 Karl Wittmann per phase.

Regards
Karl

+1 on the multigrid :)
 
Its a bloody nice unit. Does any one exist with 3 phase and larger than 3kw? I run the 3phase 10kw from mpp solar today and it works kind of like that.

The stand by is more like 300 btw on that ;) And its hard to get rid of the standby. You need to calc 40-80w per phase in idle power useage. Where 40w is on the more expensive. With that said for instance Victron have a sleep mode with 5w but that only happens when nothing is usedon the load.. That does never happen in my home!
 
If you are planning on a 10Kw 3-Phase inverter, a idle powerusage of 200W is not that important anymore... the rest of your setup (battery and solar)has to be big also, i mean a 10Kw inverter on a 5Kwh battery and 500W solarpanels is a bit silly.

A 3-Phase inverter is morelike 3 single phase inverters in one, so a idle use of 66W / inverter aint that bad.
As always, you get what you pay for, those infini solar (=MPP solar) inverters are cheap(er).
And the trick is not to have your inverter in stand-by, a inverter in standby is kind of useless, right? ;)
 
I understand the Victron might be able to measure my grid consumption (or feed-in) by using some kind of shuntmeter or AC clamp, but I don't want that. I want it to be software controllable as I already have all the meters in place, and I dont want to add additional meters and additional wiring to and from my panel to the Victron

So I want either TCP, HTTP, RS232 or RS485 control the charge/discharge rate.

Perhaps I can control the Victron Venus GX over IP? That would be great. Any ideas?
 
Tozz said:
So I want either TCP, HTTP, RS232 or RS485 control the charge/discharge rate.

Perhaps I can control the Victron Venus GX over IP? That would be great. Any ideas?

I use the ve.direct.protocol to control the charge current of my mppt charger.

Venus is just running on linux, so should be no problem to control it using IP. Myself I just use a simple php script.
 
"I also have 2 separate PV arrays from 2 brands (Growatt and SolarEdge), which adds to the complexity." - Are these on different single phases of the supply or the same phase ? If they are on the same phase then charge netting only needs a single phase solution...
 
They are on 2 separate phases. They need to be, because I would exceed my main breaker of 25 amps.
 
completelycharged said:
"I also have 2 separate PV arrays from 2 brands (Growatt and SolarEdge), which adds to the complexity." - Are these on different single phases of the supply or the same phase ? If they are on the same phase then charge netting only needs a single phase solution...

Tozz said:
They are on 2 separate phases. They need to be, because I would exceed my main breaker of 25 amps.

Even if they are on two separate phases, netting could still be done with a single phase solution. Your three phase electricity meter sums the power on all phases, so if you export 1kW on the 1st phase, and export 2kW on the second phase, you can null these by consuming 3kW on the 3rd phase. 1+2-3=0.

-Tim
 
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