New Powerwall Advanced Options [Toggles for charging from and discharging to grid from powerwalls]

[swedge]

Today the Export (solar/everthing) option appeared on my app, so it is time to see what it does.

Of course, it did something unexpected. As usual, it sat at 100% state of charge (SOC) till 3pm when partial peak starts. Normaly, it then takes over the house load, letting full solar export at partial peak rate. But in Export Everything, it did not, instead just sat there at 100%. OK, it is saving it's charge for the upcoming higher peak price.

Peak period started at 4pm, while solar was still producing. I expected the PW to just add it's 3.3 kW to the solar export, but that is not what it did. Instead it discharged at a rate which made the total grid export 3.5 kW or so. As solar ramped down, discharge ramped up. Likewise, consumption changes resulted in matching discharge changes.

Later on, when solar had faded down to .1kW, PW is discharging ar 4.4kW, 1.4 for the house, and 3.2 for export. So it still seems to be adjusting it's discharge to keep the total grid export around 3kW. That is interesting, because my solar sometimes exports close to 5kW.

I'm not sure what optimum behavior would be, and am only starting to learn what PW's programed behavior is.

SW

 

[dailo]

Today the Export (solar/everthing) option appeared on my app, so it is time to see what it does.

Of course, it did something unexpected. As usual, it sat at 100% state of charge (SOC) till 3pm when partial peak starts. Normaly, it then takes over the house load, letting full solar export at partial peak rate. But in Export Everything, it did not, instead just sat there at 100%. OK, it is saving it's charge for the upcoming higher peak price.

Peak period started at 4pm, while solar was still producing. I expected the PW to just add it's 3.3 kW to the solar export, but that is not what it did. Instead it discharged at a rate which made the total grid export 3.5 kW or so. As solar ramped down, discharge ramped up. Likewise, consumption changes resulted in matching discharge changes.

Later on, when solar had faded down to .1kW, PW is discharging ar 4.4kW, 1.4 for the house, and 3.2 for export. So it still seems to be adjusting it's discharge to keep the total grid export around 3kW. That is interesting, because my solar sometimes exports close to 5kW.

I'm not sure what optimum behavior would be, and am only starting to learn what PW's programed behavior is.

SW

I saw the same thing with partial peak, but after a few days it started discharging from PW again.

 

[bryan995]

4kw sunpower PV + 8kw Tesla PV
2xPW2 (PW2+ & PW2).

I’ve been charging from the grid for a few weeks now.

Working well! Though now I am starting to build a bit of a NEM balance. Silly question and this may be SDGE specific, but is the true-up done per TOU category?

Ie right now I am banking a ton of off-peak, some peak, and using almost solely super-off peak. Is a total net $ amount first calculated across all 3 and then used to offset bill? Or does it happen per TOU category in isolation?

Don’t yet have the export to grid / advanced options. So I am unable to discharge PWs into the grid during peak. Though not sure I need that!

F150 Lighting SR should be arriving in 2-3 weeks, so I expect super-off-peak to increase even more. May likely be pulling almost 30kwh from midnight-3am to charge the MY, F150 and 2xPW2.

 

[aesculus]

There is a setting visible through the Tesla API called "min_site_meter_power_ac" that matches my output while exporting everything. I have a 6.3 kW PV system and my setting is -7.4. I'm not sure whether this value can be provisioned through the installer wizard or is set on the backend, but it definitely seems to be scaled to the PV size. Note that there is also a "max_site_meter_power_ac" setting, which might imply that the Powerwall software could peak shave as well.

A bit of searching and found this was referenced before here: New Powerwall Advanced Options [Toggle for charging from the grid that is not stormwatch mode!]

I tried this from the user side and could not find it. What API call is this and does it only work when logged in as an installer?

 

[jgleigh]

A bit of searching and found this was referenced before here: New Powerwall Advanced Options [Toggle for charging from the grid that is not stormwatch mode!]

I tried this from the user side and could not find it. What API call is this and does it only work when logged in as an installer?

/api/site_info​

Will give you the min_site_meter_power_ac information. API information only requires the Customer login.

 

[aesculus]

/api/site_info​

Will give you the min_site_meter_power_ac information. API information only requires the Customer login.

Must of totally overlooked it because the sample was much more complete (guessing from installer ID) and these are at the top.

So my system returns 9.9 kW and my system is set at:

nominal_system_power_kW: 10

 

[dailo]

/api/site_info​

Will give you the min_site_meter_power_ac information. API information only requires the Customer login.

I guess that explains why mine doesn't throttle at all. Mine is set to max_site_meter_power_ac': 1000000000, 'min_site_meter_power_ac': -1000000000

 

[swedge]

If solar generation kicks up (temporary sun light level increase) and (Solar-household) is greater than 3.3, grid charge goes to zero.

I think I may have misunderstood this. Perhaps you meant that the grid draw goes to zero and the PW continues to charge at 3.3 kW which is supplied by the solar. That is what mine does, anyway.

Mine seems to limit the charge to around 3.3 kW, solar or grid. The spec sheet (link) says it can charge at 5 kW (7 for 10 seconds), with a footnote saying "In Backup mode, grid charge power is limited to 3.3 kW." , though I thought Backup mode means the grid is down, i.e. zero grid charge power available.

So many mysteries!

SW

 

[cwied]

Must of totally overlooked it because the sample was much more complete (guessing from installer ID) and these are at the top.

So my system returns 9.9 kW and my system is set at:

I was actually pulling from the server API rather than from the local API. I've mostly switched to using the server API because it seems to get the Powerwalls to accept settings changes more reliably. As far as I know, the local API gives the same data whether you're logged in as installer or customer, but the customer API has mostly read-only calls.

 

[aesculus]

I was actually pulling from the server API rather than from the local API. I've mostly switched to using the server API because it seems to get the Powerwalls to accept settings changes more reliably. As far as I know, the local API gives the same data whether you're logged in as installer or customer, but the customer API has mostly read-only calls.

I'd like to throttle mine back to around 5 kW. My solar never sends more than about 7 kW to the grid so somewhere below or at that would probably be best.

Did we decide yet that this setting throttles both the solar give back and the PW export as a collection? (ie if mine was set to 10 and the solar was producing 6 then export would be limited to 4).

 

[miimura]

I guess that explains why mine doesn't throttle at all. Mine is set to max_site_meter_power_ac': 1000000000, 'min_site_meter_power_ac': -1000000000

Mine must be the similar. My Summary page says "Site Import Limit: 1000 GW".

 

[h2ofun]

Many, my setup is weird. Today, I looked at my 2 gateways. One that has 2 batteries, now had energy exports, which I guess only works in TBC, but no grid charging. My GW with 3 PW's has none of the advanced options.

 

[swedge]

Did we decide yet that this setting throttles both the solar give back and the PW export as a collection? (ie if mine was set to 10 and the solar was producing 6 then export would be limited to 4).

That does seem to be how mine is behaving.

SW

 

[Fruitcake]

Storm Watch definitely charges from the grid so anyone should be allowed. You just normally don't want to do it since it's not cost efficient.

Some time ago (several months, prior to this thread), I was having issues with my PV and as such, my Powerwalls wouldn't charge. Worse, their reserves would slowly dwindle over time (a phenomenon I now know to be called "self-discharge").

I called Tesla "support" and asked if there was any way I could charge my batteries off the grid, so as to keep them at full capacity in the event of an outage. They said they could not. They went further and blamed this limitation on my a--hole utility PS&G, essentially saying they were to blame for this policy limitation.

I asked if this could be done even temporarily, until I could get my PV repaired, but Tesla refused to budge on their position.

So... what changed? Did every utility in the US suddenly relent on this limitation? Was it even a limitation to begin with, and I was just being gaslighted by Tesla until they implemented this feature? Any explanation would be appreciated.

 

[jjrandorin]

Correct. I have the PW 2

I havent been following this thread closely, but, like @skepticcyclist , I am in SCE territory. I just looked in my app and I have the export solar / everthing switch (that I did not even know existed because I have not been following this thread), as well as as grid charging no / yes.

I have a Gateway V1, as well as 2 Powerwall 2s (not plus), installed by tesla.

I didnt get to the end of the thread before posting this so apologize if people already worked out if this is utility gated or gated by something else.

FWIW, my solar is actually on a PPA agreement with tesla (so I dont own it, so "loan / Own outright" is not a gate, obviously. I do own my Powerwall 2s outright though.

 

[aesculus]

I havent been following this thread closely, but, like @skepticcyclist , I am in SCE territory. I just looked in my app and I have the export solar / everthing switch (that I did not even know existed because I have not been following this thread), as well as as grid charging no / yes.

I have a Gateway V1, as well as 2 Powerwall 2s (not plus), installed by tesla.

I didnt get to the end of the thread before posting this so apologize if people already worked out if this is utility gated or gated by something else.

FWIW, my solar is actually on a PPA agreement with tesla (so I dont own it, so "loan / Own outright" is not a gate, obviously. I do own my Powerwall 2s outright though.

Timely. Just a few posts up:

New Powerwall Advanced Options [Toggles for charging from and discharging to grid from powerwalls]

Today the Export (solar/everthing) option appeared on my app, so it is time to see what it does. Of course, it did something unexpected. As usual, it sat at 100% state of charge (SOC) till 3pm when partial peak starts. Normaly, it then takes over the house load, letting full solar export at...

teslamotorsclub.com

And there is a bit more discussion a few posts later.

 

[cwied]

I'd like to throttle mine back to around 5 kW. My solar never sends more than about 7 kW to the grid so somewhere below or at that would probably be best.

Did we decide yet that this setting throttles both the solar give back and the PW export as a collection? (ie if mine was set to 10 and the solar was producing 6 then export would be limited to 4).

Unfortunately I have no idea how this value is set. My guess it's either set in the installation wizard or set in the backend based on the interconnection information from the utility. I also don't know what would happen if solar alone is producing more than the limit. The Powerwalls might switch to charging or try to curtail the output to keep the export under the allowed value.

Hopefully Tesla will eventually give more control over how the batteries discharge when the export setting is set to everything. A more gradual discharge would make sense. This setting doesn't seem to be intended for that purpose. It's more of an overall guardrail for how much the system is supposed to export to the grid.

 

[jgleigh]

I was actually pulling from the server API rather than from the local API. I've mostly switched to using the server API because it seems to get the Powerwalls to accept settings changes more reliably. As far as I know, the local API gives the same data whether you're logged in as installer or customer, but the customer API has mostly read-only calls.

Where is the info for pulling from the server API? Can you just access it from a URL or do you need some scripting?

 

[Fruitcake]

Some time ago (several months, prior to this thread), I was having issues with my PV and as such, my Powerwalls wouldn't charge. Worse, their reserves would slowly dwindle over time (a phenomenon I now know to be called "self-discharge").

I called Tesla "support" and asked if there was any way I could charge my batteries off the grid, so as to keep them at full capacity in the event of an outage. They said they could not. They went further and blamed this limitation on my a--hole utility PS&G, essentially saying they were to blame for this policy limitation.

I asked if this could be done even temporarily, until I could get my PV repaired, but Tesla refused to budge on their position.

So... what changed? Did every utility in the US suddenly relent on this limitation? Was it even a limitation to begin with, and I was just being gaslighted by Tesla until they implemented this feature? Any explanation would be appreciated.

Further confirming that this feature works as advertised. It's wonderful! It's like Christmas morning!

This is TRULY an enhancement to celebrate.

I have been highly critical of Tesla customer service on this forum and elsewhere. But this is an important example of Tesla engineering getting something spot-on right. This was a feature that was desperately needed - the ability to charge our home batteries using any available power source, especially in the expectation of inclement weather and/or power outages (or in my very specific case, a defective PV system unable to charge the Powerwalls as intended - and being made to wait weeks for onsite service).

So I say bravo to Tesla's engineers for getting something right, and for solving a longstanding circular dependency problem with how the Powerwalls are charged and how those levels of charge are maintained, especially in adverse conditions.

 

[aesculus]

Further confirming that this feature works as advertised. It's wonderful! It's like Christmas morning!

This is TRULY an enhancement to celebrate.

I have been highly critical of Tesla customer service on this forum and elsewhere. But this is an important example of Tesla engineering getting something spot-on right. This was a feature that was desperately needed - the ability to charge our home batteries using any available power source, especially in the expectation of inclement weather and/or power outages (or in my very specific case, a defective PV system unable to charge the Powerwalls as intended - and being made to wait weeks for onsite service).

So I say bravo to Tesla's engineers for getting something right, and for solving a longstanding circular dependency problem with how the Powerwalls are charged and how those levels of charge are maintained, especially in adverse conditions.

I suspect, but don't know for sure, that initially most installs were based on coupling with solar and in the US (taking the ITC) would prohibit you from charging from the grid. To make it simple for people to comply, without recording their solar storage activity, Tesla just defaulted to 100% solar storage only.

Somewhere they either changed their install base to a higher non solar makeup or decided they did not want to be the storage police any longer.