Tesla Energy appears to have their hands full building the current products. I would not expect 3-phase Powerwalls unless one of their already announced initiatives like one of the virtual power plants requires it or would benefit from it. 6 months sounds like a good time to ask again.
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[EU] Powerwall and 3-phase 400VAC
- Thread starter widodh
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- Powerwall Tesla Energy
The only inverters that can do this reliable is using 3 SMA Sunny Island where 2 of them are in slave mode.
They can connect to a battery on one side and to the 3-phase network on the other. If you provide a cutt-off switch to the net you can use them as backup in case the grid fails. When the grid comes back, they sync to it and then release power to the grid.
We have a set of them operating at our company linked to a 35kWh NiFe battery bank.
At home I have a 3-phase SolarEdge inverter and waiting patiently for a 3-phase powerwall 2/3 to come out. The goal is to never inject any power in the grid so I can stop paying the high annual inverter tax.
They can connect to a battery on one side and to the 3-phase network on the other. If you provide a cutt-off switch to the net you can use them as backup in case the grid fails. When the grid comes back, they sync to it and then release power to the grid.
We have a set of them operating at our company linked to a 35kWh NiFe battery bank.
At home I have a 3-phase SolarEdge inverter and waiting patiently for a 3-phase powerwall 2/3 to come out. The goal is to never inject any power in the grid so I can stop paying the high annual inverter tax.
I got tired of all the waiting and this Summer I got a Fronius Symo Hybrid 5.3 and an LG Resu10H battery. Very good system so far.
Ended up here searching for Tesla 3 phase powerwalls.
What the OP didn't yet mention (and not necessarily of interest to you all) is that the "salderings regeling", or the possibility to simply erase positive and negative electricity use (or use and production of electricity) against eachother will end in 2020 in the Netherlands. So balancing your own usage and your own production becomes even more important* And there are very little (read NO) decent all-in-one solutions for this yet. And a decent (3-phase) powerwall be at least a step in the right direction.
My 7kWp PV system has a daily surplus of up to 30kWh in the summer, which I obviously have no way of storing until the winter. So what I *can* do is store it and use it as much as possible for nightly usage e.g. for charging an EV (don't have one yet but one can dream) and for cooking (still on natural gas right now).
BTW, I am as of yet still on a single phase connection. I do not know if I can get a 3 phase connection, but chances are pretty good that I can as it is, as said, quite normal.
A single phase connection will be a 35 or 40A main fuse (not accessible for the end-user, so blowing it will need a visit from the electricity company $$$), a 3 phase connection will be 3x25A for the same fixed cost. Anything more, like the 3x40A from the OP or the 3x63A from a house a few doors down without a natural gas connection, will be more coslty in fixed yearly costs.
End result is that I will keep searching for a solution and will keep an eye out for the Tesla solution. But also the PowerEdge solutions, as I might increase my PV to ~10kWp and if so, I will add poweroptimisers and a 10kW 3 phase PowerEdge inverter.
*It is still not clear, but this is how it might be, now and after 2020:
Say you use 4000kWh is a year and supply 3000kWh back into the grid. A kWh is 25cents. You can subtract the 3000kW you supplied into the grid from the 4000kWh you used (btw: my old Ferraris meter does this automatically, so no surprise the electricity want to get rid of these meters!). So NET usage is 1000kWh times 25cents = 250euro (plus whatever fixed cost for the metering, connection, extra-cost-for-3x40A-connection, etc).
Now we are in 2021: You used 4000kWh and supplied back 3000kWh. Say 1000kW was actually made by your solarpanels and immediately used in your own house, so never reached your new meter which can read used and grid-supplied electricity separately.
So the meter actually registered 3000kWh usage times 25cents = 750euro. You also supplied back 2000kWh but you can no longer erase this against your usage, so you get payed for it by the electricity company. But now they obviously don't pay you the full price (25cents of which 2/3 is government tax..., but ony the ~1/3rd which is the bare price per kWh, say 8cents). So the powercompany "pays" you 2000kWh times 8cents = 160euro.
So 2019: you pay 250euro
And 2021: you pay 750 minus 160 = 590euro
And since you will always have extra use in winter which you cannot supply with solar (right now I am happy with 3kWh on a sunny day vs. 30kWh in summer), only part of this difference can be solved with Powerwalls. But still, it may be enough to warrant an investment in them.
What the OP didn't yet mention (and not necessarily of interest to you all) is that the "salderings regeling", or the possibility to simply erase positive and negative electricity use (or use and production of electricity) against eachother will end in 2020 in the Netherlands. So balancing your own usage and your own production becomes even more important* And there are very little (read NO) decent all-in-one solutions for this yet. And a decent (3-phase) powerwall be at least a step in the right direction.
My 7kWp PV system has a daily surplus of up to 30kWh in the summer, which I obviously have no way of storing until the winter. So what I *can* do is store it and use it as much as possible for nightly usage e.g. for charging an EV (don't have one yet but one can dream) and for cooking (still on natural gas right now).
BTW, I am as of yet still on a single phase connection. I do not know if I can get a 3 phase connection, but chances are pretty good that I can as it is, as said, quite normal.
A single phase connection will be a 35 or 40A main fuse (not accessible for the end-user, so blowing it will need a visit from the electricity company $$$), a 3 phase connection will be 3x25A for the same fixed cost. Anything more, like the 3x40A from the OP or the 3x63A from a house a few doors down without a natural gas connection, will be more coslty in fixed yearly costs.
End result is that I will keep searching for a solution and will keep an eye out for the Tesla solution. But also the PowerEdge solutions, as I might increase my PV to ~10kWp and if so, I will add poweroptimisers and a 10kW 3 phase PowerEdge inverter.
*It is still not clear, but this is how it might be, now and after 2020:
Say you use 4000kWh is a year and supply 3000kWh back into the grid. A kWh is 25cents. You can subtract the 3000kW you supplied into the grid from the 4000kWh you used (btw: my old Ferraris meter does this automatically, so no surprise the electricity want to get rid of these meters!). So NET usage is 1000kWh times 25cents = 250euro (plus whatever fixed cost for the metering, connection, extra-cost-for-3x40A-connection, etc).
Now we are in 2021: You used 4000kWh and supplied back 3000kWh. Say 1000kW was actually made by your solarpanels and immediately used in your own house, so never reached your new meter which can read used and grid-supplied electricity separately.
So the meter actually registered 3000kWh usage times 25cents = 750euro. You also supplied back 2000kWh but you can no longer erase this against your usage, so you get payed for it by the electricity company. But now they obviously don't pay you the full price (25cents of which 2/3 is government tax..., but ony the ~1/3rd which is the bare price per kWh, say 8cents). So the powercompany "pays" you 2000kWh times 8cents = 160euro.
So 2019: you pay 250euro
And 2021: you pay 750 minus 160 = 590euro
And since you will always have extra use in winter which you cannot supply with solar (right now I am happy with 3kWh on a sunny day vs. 30kWh in summer), only part of this difference can be solved with Powerwalls. But still, it may be enough to warrant an investment in them.
While it might not be practical for everyone I suggest looking into increased optimization of solar resources...ie move to Spain 
. Or to California. Low winter energy use and plenty of sun for AC in summer? Better food...and well maybe pot is not legal but I don't like it anyway.
Seriously this is a very interesting thread and very useful to me as I am building out a farm with some heavy equipment that is 3phase. Appreciate all the insight!
. Or to California. Low winter energy use and plenty of sun for AC in summer? Better food...and well maybe pot is not legal but I don't like it anyway. Seriously this is a very interesting thread and very useful to me as I am building out a farm with some heavy equipment that is 3phase. Appreciate all the insight!
That is the new Backup Gateway 2. If you look at the "Backup" section, it says "Backup of Split-phase or of a selected single phase; Automatic disconnect of all phases."
For 3-phase users, that sounds disappointing to me. Most likely it means that they don't have a 3-phase inverter for the Powerwall 2 and don't have a way to maintain 3-phase relationship between 3 single phase Powerwalls when in Backup mode.
As pointed out in another thread, it's limited to 80A split phase. That is a huge step backward for North American users compared to the existing Backup Gateway 1, which has a 200A automatic switch inside.
Has anyone been able to verify this? I am looking at expanding my PV and storage (2x 5kW PV + 1xPW1), I would like to use a 3Phase solar inverter for my upgraded system and if at all possible add the storage to the DC side of it. I can't seem to find devices that support this and now notice that even PW2 doesn't really support 3Phase homes.
Also, I'm afraid in Belgium the inverters in the PW2 will add to the limit of 10-25kW you can have on your connection. In theory they could provide max power at the same time as the solar inverter, meaning in theory I could be sending more than 10-25kW to the grid.
I hope this won't be the case (my Powerwall 1 was exempt from this but we were talking about 3,2kW max. If you go 3Phase with PW2 you could send an extra 15-21kW to the grid if I'm not mistaken.
I look forward to hearing some thoughts on this. Thanks!
Powerwall 2 is AC coupled only, so your comment about "add the storage to the DC side of it" can't be done.
Each Powerwall is 5kW continuous, 7kW peak, so I don't see why you can't have one, even if it does count toward your allowed inverters on your grid connection, unless you are capped at only 10kW.
Thanks @JohanM for the hint regarding the SMA Sunny Island inverters.
It seems that since the beginning of this year 2019 there can be configured in conjunction with the LG Chem RESU 13 some quite interesting topologies. For example, - theoretically it should be possible to set up the following 3-phase 400VAC concept:
- 3x Sunny Island 4.4M
- 2x LG Resu 13
- 1x LG Resu Plus
This will give:
- 26kWh capacity
- 10kW charging- / load capability
One bad thing is that such a system is currently NOT officially allowed by LG Chem, - they support at the moment only one inverter at their 48V products. And it seems that this is also Europe-only and not available in the US.
However, the LG Chem RESU 13 is really a cost-effective solution and can be absolutely compared with the Powerwall 2. It also offers out of the box a backup functionality. And the best thing is that it is DC- not AC-coupled.
More information can be found at this German thread:
LG Chem Resu 13 - Erfahrungsaustausch - Photovoltaikforum
It seems that since the beginning of this year 2019 there can be configured in conjunction with the LG Chem RESU 13 some quite interesting topologies. For example, - theoretically it should be possible to set up the following 3-phase 400VAC concept:
- 3x Sunny Island 4.4M
- 2x LG Resu 13
- 1x LG Resu Plus
This will give:
- 26kWh capacity
- 10kW charging- / load capability
One bad thing is that such a system is currently NOT officially allowed by LG Chem, - they support at the moment only one inverter at their 48V products.
And it seems that this is also Europe-only and not available in the US.However, the LG Chem RESU 13 is really a cost-effective solution and can be absolutely compared with the Powerwall 2. It also offers out of the box a backup functionality. And the best thing is that it is DC- not AC-coupled.
More information can be found at this German thread:
LG Chem Resu 13 - Erfahrungsaustausch - Photovoltaikforum
The new Gateway 2 available in Europe and Australia supports three phase grid, but can only back up one of the phases. If you have 3-phase solar, I don't see how it can charge the Powerwall(s) when the grid is down. It seems like a half-baked solution to me. If you only need the refrigerator and lights backed up, I suppose it's workable.
If the 3-phase solar is configured as 3 L-N inverters, and the Powerwall backups up one of the L-N phases, then one of the three solar inverters could sync. If the 3-phase solar is configured as 3 L-L inverters, or 1 3-phase inverter, then none of the inverters would sync.
Which way inverters are typically connected may be stated in earlier in this thread, but I've forgotten already. : - )
Cheers, Wayne
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Without any actual experience with such a device, I assumed that a grid tied 3-phase solar inverter would shut down in a fault state if the grid was not normal on all 3 phases. Certainly it is conceivable to design an inverter to work in a more agile fashion, but I would not expect that to be desirable in many cases.If the 3-phase solar is configured as 3 L-N inverters, and the Powerwall backups up one of the L-N phases, then one of the three solar inverters could sync. If the 3-phase solar is configured as 3 L-L inverters, or 1 3-phase inverter, then none of the inverters would sync.
Which way inverters are typically connected maye be stated in earlier in this thread, but I've forgotten already.
Cheers, Wayne
Three phase power is surprisingly common in AU (I guess like split phase is in US) but of course the vast majority of loads are single phase. Three phase is typically only required for large AC.
Solar, historically, is almost always single phase even when the home has three phase power.
Powerwalls are being sold into AU to be added to homes that already have Solar - not part of a solar and powerwall simultaneous install.
So, if you have a house that has three phase power (really only needed for the AC), and already has single phase solar, then gateway 2 is a pretty good fit; you have a single phase that is backed up, and as part of install you move critical loads to that phase. PV keeps running in this scenario, and although AC doesn't, it wouldn't have run without the PW2 anyway.
I thought the idea behind 3-phase service to the home was to balance the phases. That means that the single phase circuits should be split up and balanced across the 3 phases on your (what do you call it?) consumer unit. If you move all your critical loads to one phase, won't it be inherently imbalanced? On the other hand, I suppose if you're getting a Powerwall in AU you're very likely to be using it in Self Powered Mode so that phase will probably end up having less grid load on it than the others. Does the grid operator tell your installer which phase to put the Powerwall(s) on so they can balance the neighborhood?
I have actually never seen a single family residential service in the USA that was not split phase. 120VAC is just insufficient, so the opposite 120V is necessary to make 240V any high power loads. I suppose a small apartment would be only 120V and all on the same phase, but the other units would be on the other phase or other two phases in a 3-phase service to the building. 3-phase for residential apartments or condos and small commercial is 120Y208V service.
I have actually never seen a single family residential service in the USA that was not split phase. 120VAC is just insufficient, so the opposite 120V is necessary to make 240V any high power loads. I suppose a small apartment would be only 120V and all on the same phase, but the other units would be on the other phase or other two phases in a 3-phase service to the building. 3-phase for residential apartments or condos and small commercial is 120Y208V service.
3-phase solar is very common in EU (Netherlands in my case). Anything above ~5kW solar needs to be connected to three phase.
The house I'm building right now will get 11kWp of solar and thus will be connected 3-phase.
I could live with just backup on one phase so I can run my:
- Fridge
- Ventilation system
- Critical lights
- WiFi router and access points
- CCTV system
Other things which won't work:
- AC/Heat pump
- Warm water
- Car chargers
The idea is indeed to balance phases.
Not all appliances are three phase, but once they become big they'll be three phase. My AC/Heatpump for example can draw up to 10kW 400V 3-phase. Same goes for both our Model S which can draw 17 ~ 22kW from 3-phase 400V.
The voltage between L-N is 230V and L-L is 400V.
Other appliances like ovens and boilers are usually 2 ~ 3kW, but you spread them over the phases to keep them balanced.
Again, I could live with 1-phase power backup, just need to know it works.
