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

[swedge]

I have 3 PWs and NGOM

getakey,

Does your NGOM data show up on your black&white detailed bill? If so, does it show the monthly total solar production and limit your export credit to that number of kWh? Or does it somehow compare export to production on an hour by hour basis.

With only one PW, mine shows the estimated maximum production and limits the credited export to that amount.

I ask because some have suggested that a NGOM "interval" meter eliminates any benefit from exporting stored solar. But if they just use the monthly total production, export of stored solar during peak times could still be beneficial to both the customer and the utility.

Thanks,
SW

 

[swedge]

Nope

Sigh! I still have my fingers crossed for you.

I'm still waiting to see if tear two (intentional misspelling, I'm not really crying over this) is going to add the export option to mine. I did get grid charging, but export is missing from my app. As is the cost impact info. Like you said, configuration glitches.

SW

 

[getakey]

getakey,

Does your NGOM data show up on your black&white detailed bill? If so, does it show the monthly total solar production and limit your export credit to that number of kWh? Or does it somehow compare export to production on an hour by hour basis.

With only one PW, mine shows the estimated maximum production and limits the credited export to that amount.

I ask because some have suggested that a NGOM "interval" meter eliminates any benefit from exporting stored solar. But if they just use the monthly total production, export of stored solar during peak times could still be beneficial to both the customer and the utility.

Thanks,
SW

I'll have to look more carefully. I don't see anything obviously labelled as NGOM

 

[getakey]

I'll have to look more carefully. I don't see anything obviously labelled as NGOM

Actually there is a Table labelled "(E162_NEM PS) Metered Export Calculation"

It has:: Grid Usage, Exported to Grid, Metered Generation, Generation Eligible for Credit, Billed Usage

My exported is always less than the metered generation. There's a note that says:
Generation eligible for credit = The lesser of Exported to the Grid amounts and Metered Generation

 

[wwhitney]

Or does it somehow compare export to production on an hour by hour basis.

IIRC from reading the tariffs, it's supposed to do that. Whether the billing system actually does that, I don't know. I also think the tariff should be changed to only do it on a billing cycle basis, but that would require action by the CPUC.

Cheers, Wayne

 

[getakey]

There's only one row in the Metered Export Calculation so no way to know if they do it 15 minutes, hourly, or cumulative for the month

 

[h2ofun]

Sigh! I still have my fingers crossed for you.

I'm still waiting to see if tear two (intentional misspelling, I'm not really crying over this) is going to add the export option to mine. I did get grid charging, but export is missing from my app. As is the cost impact info. Like you said, configuration glitches.

SW

When I asked about the export option, was told it should be there when the grid shows up. I would call them

 

[aesculus]

I'm still waiting to see if tear two (intentional misspelling, I'm not really crying over this) is going to add the export option to mine. I did get grid charging, but export is missing from my app. As is the cost impact info. Like you said, configuration glitches.

When you crack this nut I will probably follow with your facts. Not worth my time until we find out what setting is missing, set wrong or understood wrong.

Thanks for taking one for the team to figure this out.

 

[swedge]

It has:: Grid Usage, Exported to Grid, Metered Generation, Generation Eligible for Credit, Billed Usage

Very interesting! Mine (again single PW) has the same columns, except instead of "Metered Generation" mine says "Estimated PV Generation". The calculation is right there on your bill, and the numbers are for the whole month. To do it hourly, there would need to be a column of "Interval Export in Excess of PG Generation" or some such. I could be wrong, but this pretty Cleary suggests that the limit on export>generation is done on a monthly basis not instantaneous.

(Caveat on this: if one opted not to have NGOM then non-export from storage is the rule.)

I think this means that folks with 3 PW and NGOM can, in fact, benefit from exporting surplus solar during peak times.

I don't recall seeing anything in the tariffs about an interval calculation, or about not exporting stored solar energy. My understanding is the what the utilities don't want is re-exporting exporting grid charged energy, and this is why they either estimate or measure solar production. For larger systems, the excess of the estimated production over actual production can be significant, hence the forced choice between NGOM or no-export at all. But every time I look at the tariffs I find some detail I didn't notice before.

But what the tariff says, what utilities do and what Tesla allows can all be quite different.

I do hope I'm right on this for all the 3+ PW owners.

SW

 

[swedge]

When you crack this nut I will probably follow with your facts.

It seems that different support agents inside Tesla have very different information on this. Perhaps one of us who does get Tesla Energy Support to enable their Grid Charging or Energy Export options could share the name of that support person who understood the issue and knew how to fix it. This could help us direct other support agents to someone inside who knows the answers. Think of it as helping Tesla manage it's inside training from the outside.

As for less informed agents, so I have spoken with Jennie Remind and Jean, neither of whom had a clue, though both opened cases and escalated to tier 2.

 

[h2ofun]

It seems that different support agents inside Tesla have very different information on this. Perhaps one of us who does get Tesla Energy Support to enable their Grid Charging or Energy Export options could share the name of that support person who understood the issue and knew how to fix it. This could help us direct other support agents to someone inside who knows the answers. Think of it as helping Tesla manage it's inside training from the outside.

As for less informed agents, so I have spoken with Jennie Remind and Jean, neither of whom had a clue, though both opened cases and escalated to tier 2.

Brandon Young is the one helping me

 

[Mark Purcell]

Had anyone outside the US received access to these advanced options?

I'm in Australia and manage to workaround grid charge/ discharge with some TOU settings, but it would be nice to have direct control.

My Powerwall2 is on version 22.9.1 bce98cad, and I'm on Android app Version 4.8.0-1025, which should be recent enough.

 

[clos000]

I love this feature! So can we use this to charge our powerwalls during offpeak or would this incur the wrath of PG&E?

 

[swedge]

So can we use this to charge our powerwalls during offpeak or would this incur the wrath of PG&E?

PG&E is completely fine with solar customers charging their batteries from the grid, as they are with non-solar battery systems. The one thing they do not like is charging from the grid during off peak, and then exporting during peak. To police this, they either estimate or measure your solar production, and limit NEM credit accordingly.

The NEM tariff says about storage systems (Special Condition 11, c, 2) :

"Note that the storage device is not required to be exclusively charged by the REGF. (renewable energy generation facility, i.e. the connected solar)".​

PG&E's web page on batteries (link) says:

"Potentially reduce your energy costs: If you’re on the Home Charging EV2A rate or a Time-of-Use rate, your battery can charge when electricity is cheaper and discharge for use in your home when electricity is more expensive."​

The one potential snag is not from PG&E or Tesla, but rather from the IRS. Batteries charged "exclusively" from solar are eligible for the same income tax credit (ICT) as the solar itself. So, if you take the tax credit IRS thinks you can not charge from the grid. No one seems to know if or why Storm Watch does not break this rule.

I, for one, did not take the ITC, and am very pleased that Tesla finally gave us that option to grid charge the Tesla App.

Tesla also added a feature to allow us to discharge and export excess stored solar to the grid during peak periods. My app does not yet have this option, but I have asked support to enable this.

Between these two features, we should be able to receive more credit for exported energy and less cost on low solar production days.

SW

 

[Dave EV]

Tesla also added a feature to allow us to discharge and export excess stored solar to the grid during peak periods. My app does not yet have this option, but I have asked support to enable this.

How long has this been possible? This is a game changer as it allows you to maximize the ROI on the Powerwall. Do you know what controls are available around that feature?

 

[dailo]

How long has this been possible? This is a game changer as it allows you to maximize the ROI on the Powerwall. Do you know what controls are available around that feature?

There is a link in the first post that goes over the options. I’ve been exporting about 40% of my PWs during peak daily, but maybe makes more sense to wait till summer rates start as the delta is larger between off peak and peak.

 

[swedge]

How long has this been possible?

It looks like Tesla released the new version of the app in April.

Skim through this thread, as several folks have described and posted screen shots of how the Cost Savings behaves with these features enabled.

For me, grid charging starts at the end of peak price period (midnight on PG&E's EV2-A), and charges at 3.3 kW. Mine slows down when it gets to 95% when grid or solar charging.

I'm still waiting to get the Export Everything option on mine, and the economic benefit from that may be significantly larger than grid charging.

SW

 

[sunwarriors]

For folks who are net exporters in general, it really doesn't make sense to force the PWs to export to the grid during on-peak since it will cycle/degrade your batteries faster I think.

You'll only be credited $0.02-$0.03 (since you're net exporting anyways) for all the extra. Are a lot of early adopters pretty balanced in terms of import/export?

 

[NathanielHrnblwr]

Based on this it looks like there may be some feature with vehicle charging coming out, maybe an automated way to use excess solar to charge.

If only. I've been waiting on this ever since they allowed this when the grid is down.

 

[holeydonut]

For folks who are net exporters in general, it really doesn't make sense to force the PWs to export to the grid during on-peak since it will cycle/degrade your batteries faster I think.

You'll only be credited $0.02-$0.03 (since you're net exporting anyways) for all the extra. Are a lot of early adopters pretty balanced in terms of import/export?

After a year of studying my NEM2-PS bill, it didn't quite work the way you said (at least, I don't experience it that way under NEM 2.0).

For example, in the previous annual true up cycle, my house took from PG&E 5,440 kWh. But I only exported 5,189 kWh. At first blush, I would have a NEM deficit and a true up bill right? Since my exports were less than imports?

However, I actually ended the year with a total combined generation + distribution NEM credit of about $150 (which PG&E just deletes when the NEM cycle resets). This is because for the annual kWh exported that is less than the annual kWh imported, they give me credit for the spot rate (peak, shoulder, off).

So when I export at noon, I get the off-peak rate. But if I export from 3pm to 4pm under EV2A, my NEM bank got the credit at the higher/shoulder rate. And for the rare peak 4pm to whenever exports, I got the peak EV2A rate.

So my understanding is that if I bank some solar in a Powerwall during off-peak, then export during peak... I get the higher rate (and even more credits) without actually generating more solar power. Basically I push my power out there when it's more valuable. I'll need to do this to charge my EVs without becoming a net NEM importer.

However, keep in mind these these credits vanish at the end of the NEM cycle. PG&E doesn't pay them out. If I export 5,000 kWh all at peak, and use 6,000 kWh from off-peak, I'd have like a $1,000 credit that gets reset with no cash payment or bill credit.

The $0.02-3 you speak of is the value of the kWh exported in excess of imports. This is actually paid out as cash or a bill credit.

At least, that's my understanding. Because PG&E blocked me from adding enough solar panels to be truly break-even on a NEM basis, I'll never know what it feels like to be h2ofun with lots of solar.