I see. For some reason (because I have solar I think) I'm not allowed to export the battery to grid, except for VPP events. So yeah, typically during the VPP hours I'm discharging to the home because I have it set on TOU so it's exporting all my solar and minimizing my home use during peak times by running off the Powerwall. When I do the calculation, the incentive is $0 for me and if I take my backup reserve close to 0%, it's like $4.50.
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Tesla Virtual Power Plant in CA
- Thread starter power.saver
- Start date
One thing to note is that on event days you will draw from the grid during peak until the event hours, so even if you're using the same amount of energy from the Powerwalls, concentrating them in the event hours may give you a small benefit.
So from this comment, if someone is self powering their loads and discharging their PWs after 4pm normally outside of an event, that stuff is added to the baseline calculation in terms of payment so it's reduced?
I was under the impression that it's all gravy and they only looked at PW export to grid (which in hindsight, doesn't make much sense) so everyone would get their $2/kWh * amount discharged - $0 (since none was exported to the grid). I suppose someone can just keep paying max Peak rates and keep PWs at 100% so it's neither discharged or exported, but that's 10 days worth.
GenSao
Member
I believe the information is included. For now the peak power of 25.3 MW from the Tesla VPP is much smaller than the 3,360 MW of peak power provided by batteries to the grid (from the day prior).
Thats how I understand the information presented from both @Redhill_qik and @cwied.
If "normally" (as in the past X days) you discharge 5kWh of energy from your batteries "somewhere" (doesnt matter where, grid or home), during the target VPP time, and during the VPP time you discharge 9kWh of energy, you would get compensated for 4kWh, is what it sounds like to me.
In simple terms it appears that they are compensating for contributing "more than you normally do", not just "contributing".
Not really, but also a sort-of. You have a battery because you have solar and as part of the original interconnect agreement to get PTO you agreed to only allow the solar inverter(s) maximum AC rated amount to be exported to the grid and battery export was not allowed as that in combination with the solar export would exceed your maximum amount. Between then an 2021 some meeting of the minds has occurred between the California IOUs, the CPUC and Tesla that the maximum amount exported to the grid can be controlled reliably through software and we got the 2021 pilot program, the 2022 VPP demonstration program and the 2022 Export Everything feature. Well some of us got the Export Everything and some of us have not had it active in the app, but if you call Tesla they sometimes waffle a bit, say that it can't be done and then magically appears in the app.
If you are/were using Export Everything regularly and it extended into the VPP event hours then that becomes a very large baseline. If your EE was basically done by 6:00pm with all/most of it discharged from 4:00-6:00pm then your baseline for most of the event hours of 6:00-9:00pm is zero, so you would compensated for all of the discharge during the event.
skepticcyclist
Member
I just hope we never get to a point where it is no longer optional, but instead required, for all homes with battery backup to be part of the virtual grid.
I would participate if I had at least one more battery.
I would participate if I had at least one more battery.
To clarify, that is one option (the most common?) for how the interconnection agreement can be filled out. It's also possible to have an interconnection agreement that allows a higher export rate than just the solar inverter size. Also, I believe that with PV plus ESS NEM in CA you are always allowed to export from the ESS if it was charged from PV and your net grid export stays below your PV inverter size. [Not sure if that's "the interconnection agreements always allow that" or "you are always allowed to have an interconnection agreement that would allow that."]
Which, if you are on NEM1, is an (undesirable) incentive to stick with equal Peak import/export prices in the PW configuration, as that will dump everything as quickly as possible at the start of Peak. Versus setting the export price slightly less than the import price (as it is on NEM2) to smooth out the Export Everything behavior.
Cheers, Wayne
For self purchased ESS I think it would be a big stretch to make this a requirement, but conceivably there could be a requirement for NEM 4.0 that in order to get credits you need to have ESS and you must allow discharging down to 35-50%.
The other side where it would be a much easier requirement is for the SGIP program. If you want the SGIP rebate then you must allow discharging down to 35-50%. The Vermont Green Mount Power utility does this already Small Vermont utility quietly builds fleet of 4,000 Tesla Powerwalls
Exactly. The second factor is that Tesla has opted to do "sub-metering," meaning only the Powerwall output is measured, not anything past it. This is nice because it means you don't get penalized for increased AC usage during the event. There's a more complicated adjustment for direct participants in the ELRP that attempts to do the same thing by looking at a baseline of hours prior to the event and comparing it to the event day.
I made sense to me that it's all gravy. I mean, PG&E didn't have this extra energy before and now they do and should pay a premium for it since it's during an emergency.
Here is the PG&E VPP Fleet Home data that I collected for the 9/7 event at 10 minute intervals. At 4:00pm when charging stopped it was at 941 kW, so not all Powerwalls were at 100% and more than all but the 9/1 event. The peak discharge was at 6:10pm at 25,897 kW with an estimated 50.4 MWh delivered during the event with 3,630 homes which are the new records.
aesculus
Still Trying to Figure This All Out
I wonder why so short? That seems inconsequential. I prepared for a much larger event so I will probably need to adjust my strategy a bit.
EDIT: Does anyone know if I can opt out of the event and have my PWs run in Cost Savings mode today, but then right before the event I can opt back in? That way I don't take a bigger hit from 2-5 using peak power (we are socked in with smoke and don't think solar will offset my draw then). I'll have plenty of power to do both I suspect.
Not sure what will happen on the back side since for every event so far I got to my reserve before the event even ended. Hopefully for this event I will have enough left to run from the PWs afterwards.
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My guess it is the predicted evening cooling that is making the event short. When I looked at the temps by the hour here in Pleasanton it looks like they are dropping quickly this evening.
FWIW I joined VPP recently. Prior to it my "min_site_meter_power_kW" (maximum export) was set at -2.7, which is the size of my (10 year old) PV inverters. 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.
Cheers, Wayne
Cheers, Wayne
Do we know that the VPP behavior does not make the obvious optimization of only reserving (|min_site_meter_power_kW| * VPP export duration) of PW available capacity (current capacity - reserve) and allowing the rest to still be used during Peak as normal?
Seems like if we don't have data on that, it would be a good test to leave the settings alone and see what you system does.
Cheers, Wayne
In the 6:00-7:00pm event on 9/1 when the event was over the normal Powerwall behavior returned and mine continue to discharge down to the reserve level that I had set. So for today's during the 4:00-5:00pm we should expect no Powerwall discharge, max allowed discharge from 5:00-6:00pm, and then normal behavior covering house loads from 6:00-9:00pm to the reserve level that you have set.
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