Discussion: "Powerwall +"

[JeremyWhaling]

Really chomping at the bit to know the price for one PW+ and ~4kW of solar. I already brought it up for our solar expansion project and got rejected by my better half. But if it had a better price than the current equivalents I might get somewhere...

With demand for PW2 the way it is, I can’t really see them reducing the cost all that much but I am hopeful.

 

[oholladay]

This is the answer I'm looking for: which (Tesla) components would I need to drive my AC, at night and without the grid? Before PW+, the Tesla configurator suggested 3 PW for my fully electric house, mainly to drive the AC units. Is this even possible with the PW+, given the 50A overcurrent protection limit? You mention SureStart as a way to mitigate the current spike when starting the compressor, and that it didn't work in your case. The Powerwall+ brochure says it includes an "integrated soft starter capable of powering motors and air conditioning units (supports devices up to 105 LRA)." Unfortunately, my AC lists 140 LRA (Locked Rotor Amps).

Do you know what kind of compressor you have? This Tesla website indicates that, if you have a scroll compressor, you can start an AC with 140 LRA with 3 Powerwalls. What Does Powerwall Back Up | Tesla Support

 

[wonder_bats]

The photo appears to show an electric meter adapter, which I assume would be a grid disconnect device (Microgrid Interconnect Device). Note that the meter shows two locking rings, one would be to lock the adapter to the all-in-one-panel, and one would be to lock the meter to the adapter. Plus there is the small flex conduit going from the top component of the Powerwall+ to the meter adapter.

So that would clarify the tweet about not having to change out main panels anymore. There's still the question of complying with the 120% rule, as the Powerwall+ appears to just be connected into the main panel. I suppose it is possible that they have CTs on the service conductors (edit: or are reading information from the smart meter) and can list the whole thing as a Power Control System so that the current going to the loads does not exceed the bus rating (or perhaps 120% of the bus rating).

Cheers, Wayne

this is a really dumb question, but are these microgrid interconnect devices a common thing? (i mean outside of transfer switches etc)

I ask because all the battery installers I talk to in my area want to install a sub-panel to isolate powerwalls from back feeding the main grid by placing the gateway in the middle.

if such a device could be easily (no idea how hard) be retrofitted over the meter input, shouldn't that be the way to go for everyone?
I also noticed some of the smart panels being advertised also come with a built in grid disconnect, but it's not clear to me if this is something available already.

 

[wwhitney]

@wwhitney would the NEC rules on taps allow a connection between the meter (meter isolation adapter) and main breaker panel if the PW also had a properly rated disconnect?

Yes, a meter adapter could implement a splice in the service conductors, so you'd effectively end up with two services.

A safer way to do it would be to put OCPD in the meter adapter (confining the second service to inside the meter adapter); then the cable coming out the side would be a feeder, and the only applicable limitations on how it is routed are those related to exposure to damage. Or the cable coming out could be service conductors, going to a disconnect right next to the existing main disconnect. That could either be a main breaker built into a PW+ or Gateway2, or a standalone disconnect, with a feeder to a possibly distant PW+ or Gateway2.

Not sure which approach existing meter adapters take (for renewable energy tie-in or for a generator transfer switch), whether they incorporate OCPD.

Cheers, Wayne

 

[wwhitney]

this is a really dumb question, but are these microgrid interconnect devices a common thing? (i mean outside of transfer switches etc)

I ask because all the battery installers I talk to in my area want to install a sub-panel to isolate powerwalls from back feeding the main grid by placing the gateway in the middle.

Currently the Gateway is the Microgrid Interconnect Device. So the Gateway has to be between the grid and anything you want on your microgrid - PWs, PV, loads.

Cheers, Wayne

 

[wwhitney]

That's my concern -- it might take a long time to get it approved by PG&E and the local AHJ.

Well, it's worth mentioning that there are currently generator transfer switch meter adapters, and a Microgrid Interconnect Device is simpler. The former is effectively a DPDT Center Off switch, while the latter is just a DPST switch. Hopefully that means there's an established listing standard and it won't take long for Tesla to get it UL listed. As to getting POCO approval, I don't know how that works.

Cheers, Wayne

 

[Yonki]

If you were able to take the main breaker and redirect that feed to the gateway and use the main panel as a sub, this whole thing would make sense and you could have multiple Powerwalls. The box on the top of the Powerwall + would just be a combined Gateway 2 and Tesla Solar Inverter in one enclosure. The problem is that it's not legal to do that with a lot of main panel designs. It would work great with my panel, but there are a lot of panels out there that don't work that way.

I've been looking for a panel that supports that - can you tell me what panel you have that does? Thx

 

[wonder_bats]

Currently the Gateway is the Microgrid Interconnect Device. So the Gateway has to be between the grid and anything you want on your microgrid - PWs, PV, loads.

Cheers, Wayne

right i understand what.

What i meant is that the photo seems to show some kind of connection from the powerwall+ back to the integrated meter / panel.
If as you say this is a disconnect adapter, i wasn't aware something like that existed that would retrofit directly on the meter.

 

[wonder_bats]

right i understand what.

What i meant is that the photo seems to show some kind of connection from the powerwall+ back to the integrated meter / panel.
If as you say this is a disconnect adapter, i wasn't aware something like that existed that would retrofit directly on the meter.

o i just noticed in an earlier reply you already said you're not aware of something like this commercially available.
oops! sorry!

 

[wonder_bats]

I've been looking for a panel that supports that - can you tell me what panel you have that does? Thx

from what i'm reading (i don't personally know anyone who has done this), the SPAN smart panel has a built-in grid disconnect switch. The idea I think is that it would allow you to do what you're describing. In the event of an outage, the panel itself would disengage from the grid, and the main panel would effectively act like a subpanel powered by a battery.

However, I don't think this company has any collaborative relationship with Tesla, and I'm fairly certain there is overlap functionality in both offerings.

 

[tfan2018]

I placed an order but it hasn't been installed yet, not for another month+. Will it be powerwall+ or powerwall 2?

 

[h2ofun]

I placed an order but it hasn't been installed yet, not for another month+. Will it be powerwall+ or powerwall 2?

for all practical purposes, completely different products

 

[tfan2018]

for all practical purposes, completely different products

how so? isn't pw+ the newer version / next gen of pw2?

 

[mongo]

how so? isn't pw+ the newer version / next gen of pw2?

There is the PW+ battery unit with higher output power, and there is also the solar PW2 which combines the PW+ battery unit with a separate-but-connected top solar module.

 

[MP3Mike]

how so? isn't pw+ the newer version / next gen of pw2?

No. Different product intended for simplifying solar installs that have a Powerwall.

 

[sunbear]

This week I'm having a 15.12kW solar + 3 Powerwall system installed at my home in NJ by an tesla-certified 3rd party installer (not Tesla themselves). Since the PWs are backordered, the installer will be coming back to install the PWs when they are available around August 2021. The current design includes a 200A Generation Panel with 30A breakers for each PW, but the spec of the PW+ indicates that now 50A breakers are required to take full advantage of the increased peak current of the PW+. I'm thinking that I should request that they install 50A breakers now so that they don't have to change things come august (most likely I'm going to get PW+ since it's so long after the November 2020 manufacture date when Tesla switched from PW to PW+).
What do people think?

 

[miimura]

This week I'm having a 15.12kW solar + 3 Powerwall system installed at my home in NJ by an tesla-certified 3rd party installer (not Tesla themselves). Since the PWs are backordered, the installer will be coming back to install the PWs when they are available around August 2021. The current design includes a 200A Generation Panel with 30A breakers for each PW, but the spec of the PW+ indicates that now 50A breakers are required to take full advantage of the increased peak current of the PW+. I'm thinking that I should request that they install 50A breakers now so that they don't have to change things come august (most likely I'm going to get PW+ since it's so long after the November 2020 manufacture date when Tesla switched from PW to PW+).
What do people think?

Discuss it with the installer before they do the work. They should be able to contact the right people at Tesla to make sure the design is correct for the system going forward. However, it may require modifying your permit.

 

[mongo]

This week I'm having a 15.12kW solar + 3 Powerwall system installed at my home in NJ by an tesla-certified 3rd party installer (not Tesla themselves). Since the PWs are backordered, the installer will be coming back to install the PWs when they are available around August 2021. The current design includes a 200A Generation Panel with 30A breakers for each PW, but the spec of the PW+ indicates that now 50A breakers are required to take full advantage of the increased peak current of the PW+. I'm thinking that I should request that they install 50A breakers now so that they don't have to change things come august (most likely I'm going to get PW+ since it's so long after the November 2020 manufacture date when Tesla switched from PW to PW+).
What do people think?

Critical factor is if the panel can support the 50A breakers/ powerwalls. If so, they could wait to install the breakers themselves when they put in the PW.

 

[MP3Mike]

This week I'm having a 15.12kW solar + 3 Powerwall system installed at my home in NJ by an tesla-certified 3rd party installer (not Tesla themselves). Since the PWs are backordered, the installer will be coming back to install the PWs when they are available around August 2021. The current design includes a 200A Generation Panel with 30A breakers for each PW, but the spec of the PW+ indicates that now 50A breakers are required to take full advantage of the increased peak current of the PW+. I'm thinking that I should request that they install 50A breakers now so that they don't have to change things come august (most likely I'm going to get PW+ since it's so long after the November 2020 manufacture date when Tesla switched from PW to PW+).
What do people think?

You won't be getting a Powerwall+. The Powerwall+ is an integrated system for the Solar/Gateway/Powerwall all-in-one. So if your Powerwalls aren't being installed at the same time as your solar you aren't getting a Powerwall+.

 

[mongo]

You won't be getting a Powerwall+. The Powerwall+ is an integrated system for the Solar/Gateway/Powerwall all-in-one. So if your Powerwalls aren't being installed at the same time as your solar you aren't getting a Powerwall+.

PW+ in terms of the post-Novemenber higher power handling, as opposed to the combined solar PW unit. Given Elon's update regarding high output capacity in mild temperatures, a new PW could potentially make use of the larger breaker.