Tesla Virtual Power Plant in CA

[wwhitney]

IMHO, the goal is to have the Powerwalls discharge as much as possible during the event period and to the extent possible to minimize the discharge during high likelihood event hours in the baseline days before.

The latter part is economically optimal to the extent it can be achieved while still maximizing total Peak discharge during non-VPP days. If a normal Peak discharge kWh is worth, say, $0.50, and a VPP enhanced Peak discharge is worth $2.50 total, then unless the VPP events occur more often than 1 out of 5 days, it's not worth skipping a Peak discharge kWh just to lower the VPP baseline.

If you meant 2kW/Powerwall and 4kW total that seems unusual and must mean that your solar invertor/PTO is only rated for 4kW. Have you looked at any of your baseline numbers to see if this is even worth it to you?

See the earlier post in this thread: Tesla Virtual Power Plant in CA

Cheers, Wayne

 

[Redhill_qik]

The latter part is economically optimal to the extent it can be achieved while still maximizing total Peak discharge during non-VPP days. If a normal Peak discharge kWh is worth, say, $0.50, and a VPP enhanced Peak discharge is worth $2.50 total, then unless the VPP events occur more often than 1 out of 5 days, it's not worth skipping a Peak discharge kWh just to lower the VPP baseline.

In this case it is YMMV, I am a net generator and would end up with a NEM 2.0 credit without any use of Powerwalls to reduce my Peak consumption. if you are a net consumer as you likely then the equation is different.

See the earlier post in this thread: Tesla Virtual Power Plant in CA

> But upon joining Tesla bumped it up (in magnitude) to -4.0. Which is fine as my PTO allows both PWs to export, or -12.7.
Very confused by this, but if your two Powerwalls combined are only putting out 4kW then the Tesla software thinks otherwise. Is the 12.7 from the interconnect agreement document or is it from logging into the Tesla gateway and looking at the Summary tab?

Cheers, Wayne

I see this and think this

 

[wwhitney]

Very confused by this, but if your two Powerwalls combined are only putting out 4kW then the Tesla software thinks otherwise.

Why would it think otherwise? It used to throttle net export (jointly) to 2.7 kW (my old PV AC size, approximately) and now it throttles to 4 kW, and that's the behavior I'm seeing, per the app. I'm sure I could change the export limit higher if desired, either myself or via PW technical support, but I don't see any upside.

The 12.7 I thought was from my Interconnection agreement, which I filed myself (self-SGIP). Except looking at the application, I don't actually seeing anything definitive on PW export (the older 2017 form doesn't have some of the fields I've seen here on more recent forms). The PTO does say "Total Effective Inverter Nameplate Rating: 12.446 kW Inverter" so I think that covers me.

Cheers, Wayne

 

[Redhill_qik]

Why would it think otherwise? It used to throttle net export (jointly) to 2.7 kW (my old PV AC size, approximately) and now it throttles to 4 kW, and that's the behavior I'm seeing, per the app. I'm sure I could change the export limit higher if desired, either myself or via PW technical support, but I don't see any upside.

The 12.7 I thought was from my Interconnection agreement, which I filed myself (self-SGIP). Except looking at the application, I don't actually seeing anything definitive on PW export (the older 2017 form doesn't have some of the fields I've seen here on more recent forms). The PTO does say "Total Effective Inverter Nameplate Rating: 12.446 kW Inverter" so I think that covers me.

My confusion is from you saying that you can export up to 12.7kW, but Tesla only allowing up 4kW are you happy with the throttling to 4kW?

If your system ever falls under NEM 3.0 with a Grid Participation Charge that is tied to the AC rated specification it would be really bad if PG&E is using 12.446kW versus your solar invertor maximum of 4.0kW as you are looking at $99.57/month vs $32.00/month at $8/kW.

 

[wwhitney]

My confusion is from you saying that you can export up to 12.7kW, but Tesla only allowing up 4kW are you happy with the throttling to 4kW?

Well, until half a year ago, it wasn't possible to net export from the PWs at all (the feature was only 3.5 years late for me). And until this week, I was limited to 2.7 kW site net export, but I always hit my reserve level before the end of Peak, given my small PV size. And I can always change the parameter via the Installer interface if I feel like it (or ask Tesla to do it for me if I wish to play nicely). So I am not really concerned about enabling something that wouldn't provide any benefit.

As for NEM 3.0, I'll worry about that if/when it ever happens and impacts me. And to provide a sense of scale, my non-EV non-heat pump daily usage is around 10 kWh.

Cheers, Wayne

 

[Redhill_qik]

Here is the PG&E VPP Fleet Home data that I collected for the 9/9 event at 10 minute intervals. At 4:00pm when charging stopped it was at 1270 kW which is the highest so far, might be the later charging start or maybe it was a cloudier day for some sites. The peak discharge was at 5:50pm at 24,659 kW which deviates from past events as the peak was not within the first 20 mins and was lower than other days with more homes. This change is very likely due to the earlier start time with more solar production that is curtailing the amount that the Powerwalls can discharge while staying below the site export limits. Overall there was an estimated 50.7 MWh delivered during the event with 3,657 homes which are both new records.

 

[Redhill_qik]

We might be done with VPP events for the year at this point, but I am probably done with collecting data. Here is the aggregate data that I collected for the events except for the 2 hour event on 9/3 and the 3 hour event on 9/4 that I wasn't about to log due to travel on those days. There is also the lastbulb.com Tesla VPP site that has data for both PG&E and SCE.

	8/17​	8/31​	9/1​	9/5​	9/6​	9/7​	9/8​	9/9​
Total kWh	34,966​	41,809​	20,422​	48,555​	46,288​	49,390​	50,350​	50,689​
Fleet Homes	2,341​	2,792​	2,858​	3,464​	3,514​	3,592​	3,630​	3,657​
Avg kWh/Home	14.94​	14.97​	7.15​	14.02​	13.17​	13.75​	13.87​	13.86​
Hours	3​	3​	1​	3​	3​	3​	3​	3​
Peak Discharge	16,610​	18,867​	20,853​	24,711​	23,801​	25,279​	25,897​	24,659​
Peak/Home	7.10​	6.76​	7.30​	7.13​	6.77​	7.04​	7.13​	6.74​
Est Avg PWs/Home	1.45​	1.38​	1.49​	1.46​	1.38​	1.44​	1.46​	1.38​

This table is interesting to me as the average home discharge dropped after the first two events. It isn't clear why this happened, maybe the first events had more diehard discharge mindset homes with a 5-10% reserve level and maybe over time more homes became concerned about outages and raised their reserve levels.

 

[power.saver]

We might be done with VPP events for the year at this point, but I am probably done with collecting data. Here is the aggregate data that I collected for the events except for the 2 hour event on 9/3 and the 3 hour event on 9/4 that I wasn't about to log due to travel on those days. There is also the lastbulb.com Tesla VPP site that has data for both PG&E and SCE.

View attachment 851021

	8/17​	8/31​	9/1​	9/5​	9/6​	9/7​	9/8​	9/9​
Total kWh	34,966​	41,809​	20,422​	48,555​	46,288​	49,390​	50,350​	50,689​
Fleet Homes	2,341​	2,792​	2,858​	3,464​	3,514​	3,592​	3,630​	3,657​
Avg kWh/Home	14.94​	14.97​	7.15​	14.02​	13.17​	13.75​	13.87​	13.86​
Hours	3​	3​	1​	3​	3​	3​	3​	3​
Peak Discharge	16,610​	18,867​	20,853​	24,711​	23,801​	25,279​	25,897​	24,659​
Peak/Home	7.10​	6.76​	7.30​	7.13​	6.77​	7.04​	7.13​	6.74​
Est Avg PWs/Home	1.45​	1.38​	1.49​	1.46​	1.38​	1.44​	1.46​	1.38​

This table is interesting to me as the average home discharge dropped after the first two events. It isn't clear why this happened, maybe the first events had more diehard discharge mindset homes with a 5-10% reserve level and maybe over time more homes became concerned about outages and raised their reserve levels.

Nicely done @Redhill_qik

I think your right that some upped the reserve after the first few events. I know we've seen talk of that here too.

 

[Redhill_qik]

One last data dump on the compensation side. This of course is just my individual data, but I am attaching my Excel file that can be used to calculate your own. In order to do that you will need to delete all of the data in the "Data" sheet then from the Powerwall tab in the Tesla app download the daily data from 8/4 through 9/9, send it yourself (I recommend selecting Gmail and the getting it from your Draft folder), and finally copy it in to the "Data" sheet.

Day​	Date​	Period​	Hours​	Discharge​	Baseline​	ILR​	VPP​
Wed​	8/17/2022​	6:00-9:00pm​	3​	22.97​	6.07​	16.90​	$33.80​
Wed​	8/31/2022​	5:00-8:00pm​	3​	23.48​	5.66​	17.82​	$35.64​
Thu​	9/1/2022​	6:00-7:00pm​	1​	8.38​	2.20​	6.18​	$12.36​
Sat​	9/3/2022​	6:00-8:00pm​	2​	17.88​	1.50​	16.38​	$32.76​
Sun​	9/4/2022​	5:00-8:00pm​	3​	24.23​	3.93​	20.30​	$40.60​
Mon/Holiday​	9/5/2022​	6:00-9:00pm​	3​	24.88​	1.50​	23.37​	$46.75​
Tue​	9/6/2022​	6:00-9:00pm​	3​	19.89​	2.84​	17.05​	$34.10​
Wed​	9/7/2022​	6:00-9:00pm​	3​	3.93​	2.84​	1.09​	$2.18​
Thu​	9/8/2022​	6:00-9:00pm​	3​	23.23​	2.84​	20.38​	$40.77​
Thu​	9/9/2022​	5:00-8:00pm​	3​	24.29​	5.52​	18.77​	$37.55​
		Total​	27​	193.16​	34.91​	158.25​	$278.95​

Note: I had a grid outage for the 9/7 event which is why it is so low.

 

[aesculus]

Avg kWh/Home

14.94​

14.97​

7.15​

14.02​

13.17​

13.75​

13.87​

13.86​

I find this interesting. While I left my reserve at 20% with 2 PWs I output at 10 kW. That meant I should have put in 20 kWh but of course I used energy to cool my home so I was probably more like 12-13 kWh. This fits this average. It surely indicates that most users had two or more PWs and probably left some energy on the table. Clearly those who were around for the 3rd hour had three or more PWs or a really low export value.

 

[Redhill_qik]

I find this interesting. While I left my reserve at 20% with 2 PWs I output at 10 kW. That meant I should have put in 20 kWh but of course I used energy to cool my home so I was probably more like 12-13 kWh. This fits this average. It surely indicates that most users had two or more PWs and probably left some energy on the table. Clearly those who were around for the 3rd hour had three or more PWs or a really low export value.

These numbers are just what the Powerwalls are doing and the house load is not a factor. In your case you would have discharged 20kWh with your two Powerwalls, but the average home appears to be ~1.45 PWs, so 20 * 1.45 / 2 = 14.5 kWh which is close to the first two events.

 

[astrorob]

One last data dump on the compensation side. This of course is just my individual data, but I am attaching my Excel file that can be used to calculate your own. In order to do that you will need to delete all of the data in the "Data" sheet then from the Powerwall tab in the Tesla app download the daily data from 8/4 through 9/9, send it yourself (I recommend selecting Gmail and the getting it from your Draft folder), and finally copy it in to the "Data" sheet.

Note: I had a grid outage for the 9/7 event which is why it is so low.

turns out on iphone/mac it's easier to use airdrop to send the daily files. still a pain in the butt.

on a couple of VPP event days i chickened out and didn't export much and so the spreadsheet calculated a negative value for the VPP value. i just hacked those cells to return zero if the amount would be negative.

due to my EE down to 20% every day my baselines were pretty huge and according to the spreadsheet i only made $41.36. predictably i made the most on days where the event lasted till 9PM since normally my PWs hit the reserve by around 8PM.

thanks for sharing your spreadsheet, it is very useful. i had been wondering just how much $ i made in these events.

 

[Redhill_qik]

turns out on iphone/mac it's easier to use airdrop to send the daily files. still a pain in the butt.

on a couple of VPP event days i chickened out and didn't export much and so the spreadsheet calculated a negative value for the VPP value. i just hacked those cells to return zero if the amount would be negative.

due to my EE down to 20% every day my baselines were pretty huge and according to the spreadsheet i only made $41.36. predictably i made the most on days where the event lasted till 9PM since normally my PWs hit the reserve by around 8PM.

thanks for sharing your spreadsheet, it is very useful. i had been wondering just how much $ i made in these events.

Cool, I'm glad someone found it useful. Thanks for sharing your results as an Export Everything site.

 

[MY2021f]

Anyone gotten paid yet or or found how to check what you've made?

 

[Redhill_qik]

Anyone gotten paid yet or or found how to check what you've made?

Payment isn't until March 2023. There is no known way to check officially how much you have made, but there is the spreadsheet that I created that can estimate for you if you download all of the daily data from 8/4 through 9/9.

 

[MY2021f]

Interesting, thanks.

 

[charlesj]

Interesting, thanks.

When this program went on a test run there were several members here who participated and gotten paid but not at the end of the test but some time afterwards.

 

[KHYE]

i joined the last 5 VPP events and with the heat wave is returning, I'm expecting there will be VPP. During the last VPP, I think my only 1 PW exported about 2-3kw on avg to the grid. Is it possible to maximize the VPP export and how? Thanks.

 

[Redhill_qik]

i joined the last 5 VPP events and with the heat wave is returning, I'm expecting there will be VPP. During the last VPP, I think my only 1 PW exported about 2-3kw on avg to the grid. Is it possible to maximize the VPP export and how? Thanks.

Lower your reserve level to the minimum level that you feel comfortable with, because that is the level of will discharge to.

 

[KHYE]

Lower your reserve level to the minimum level that you feel comfortable with, because that is the level of will discharge to.

Mine is almost at the lowest, 5%