I was told by installer that if you have a battery with your solar you qualify. May want to give pge a call. Bec not benefiting from your battery on weekend or the whole of winter is
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Tesla Virtual Power Plant in CA
- Thread starter power.saver
- Start date
My 2 batteries have kept us going for 2 day long power outages. I bet your 5 PWs would do better!!!I personally would love to see the power go out, so I can give these batteries a try
I'm on E-TOU-C and I'm a net generator. IMHOt it will always beat E-TOU-D and will usually beat EV2A unless you have a very heavy usage from 12:00am-3:00pm.
With the summer off peak/Peak of EV2A at .25/.56 vs Tou-C at 34-43 / .40-.49 How does one get a better return with Tou C? The difference between off-peak and peak is so much greater with EV2A, so I was thinking of filling the PW at .25 and selling it at .56. Which sounds better than fill at .34 and sell at .49. I'm assuming that all the peak hours are being covered by the PW. I'll be the first to admit that this may be an oversimplification. I'm usually using about 18kWh between midnight and 3pm costing me $4.5 ev2a vs $6.12 tou-c then I sell to PGE at .56 ev2a vs .49 tou-c the rest of the time. Using more or less off peak doesn't seem to matter, since I will always be paying less during off peak and selling higher during peak. Again, this is assuming that I use only the powerwall from 3pm to midnight. The same would hold true for winter rates.
I'm always looking for ways to save. I just don't see how touc is better than ev2a in my situation. There must be a situation where it is better, otw why have it, I just can't figure out when that would be especially with the export everything button available.
Ok searched and found the answer here post #9 from you even
. thank you:
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When? Do you have an all electric house?
Summer, with lots of sun, thats one thing. Winter, little sun, and huge draw from my heat pumps, NO WAY!!!
If folks do not give the entire story, comments about what can happen mean nothing!
I was assuming you were talking about now since this a thread about VPP summertime operations. Sorry if I misunderstood your context.
We have a big fire near us last year, in like October. People had power out for like 2 weeks. Even though sun, their batteries died.
So, its the complete system. Meaning, you can have all the batteries in the world, but if you do not have enough solar panels to charge them, ...
Agreed. We could not get enough charge to keep the Powerwalls filled when we had those big fires in the hills 2 years ago. Hopefully, those will not become a regular occurrence.
aesculus
Still Trying to Figure This All Out
It will be interesting to see how it handles this three hour event today versus the two hour event yesterday. Yesterday it discharged at 10 kW (my PTO limit) for the entire two hours and go to 32%. My reserve is set for 20%.
Will it discharge at the max rate again today and probably get to the limit 45 minutes before the end of the event, or will it start throttling back? I wonder if they have some sort of algorithm in the back end that optimizes this or "just presses the peddle to the metal" and see what happens?
BTW I am going to have to increase my house temps more than I did yesterday I think to give back. Yesterday I increased them 2* above normal during peak and also for the hour after peak. Today I may need to go up to 4* or 5* to ensure I return a significant amount during the event period.
Will it discharge at the max rate again today and probably get to the limit 45 minutes before the end of the event, or will it start throttling back? I wonder if they have some sort of algorithm in the back end that optimizes this or "just presses the peddle to the metal" and see what happens?
BTW I am going to have to increase my house temps more than I did yesterday I think to give back. Yesterday I increased them 2* above normal during peak and also for the hour after peak. Today I may need to go up to 4* or 5* to ensure I return a significant amount during the event period.
I would say based on the data @Redhill_qik has posted (Tesla Virtual Power Plant in CA) that discharge is at max rate from the start of the event until the PWs reach their reserves. Note the significant drop towards the end of the event when a lot of PWs have been depleted. But what's the best way to do this? They should know what everyone's reserve is, and could discharge at a lower rate to cover the entire event, but seems they chose not to. Perhaps they have committed to an initial discharge amount based on the number of participants and need to satisfy that goal first.
There are a combination of factors. Your combined powerwall output limit, your site export limit configuration and your PTO export limit. The software cant adequately anticipate how your home loads are going to change, so going at max export until you hit reserve makes the most sense.
The main thing I have taken away from this series of events is that the capacity of storage for PW2 is undersized compared to the inverter capability when used in this grid assistance manner.
In my case we have 3 PW2 so the continuous output capability is 15 kW.
However my site export limit is 10.8 kW as configured in the gateway. This lower configured output is the only reason we are able to output for almost the entire 3 hour event window. (Usable capacity stated at 40.5 kWh and I keep a 5% reserve.)
BTW, My PTO says I can export the combined nameplate rating of my solar and ESS [~26 kW]. I dont know why the site export limit was configured for 10.8 but dont care to dig into it because it doesn’t seem useful to have it higher.
Idk if future generations will take this into consideration but I think that the storage capacity should be on the order of 3x to 4x the continuous output rating.
I think it is more a matter of the event duration. Regardless of the ESS capacity, discharging it at a rate higher than capacity/duration will cause it to run out of stored energy. The question I'm interested in is whether or not the grid operator expects a continuous supply during the event, or if the front-loading is better? I think that they would prefer a continuous supply over the entire event that they can use rather than an unknown drop-off towards the end.
I may opt out of this event. Our grid voltage sagged down to 200V and took the solar and Powerwall offline. The GW still kept us connected to the grid so I manually went off grid to get the solar back online. Unfortunately with the clouds and AC usage the solar is not quite covering home usage.
I have seen some variations in the sample data at the start which may be due to solar production still occurring which limits the amount the Powerwalls are allowed to discharge, so far the grid export limit isn't exceed. In general the Powerwalls are being discharge at the maximum rate allowed. In the three hour events you can see that some fleet homes are hitting there reserve limits and the discharging stops.
I was traveling yesterday and again today, so no 10 min sample charts from me for these events. My Powerwalls did discharge 17.8 kWh down to 31% yesterday, but didn't hit the 9% reserve that I set as it was only 2 hours. I'm back to 100% now and should go hit the 9% limit for the 3 hour event today.
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This is going to be interesting. Tomorrow's EEA Watch goes longer than the hours they said they would dispatch for the VPP. I wonder if they're going to do a four hour event tomorrow (5pm-9pm). I'm not sure I remember a Flex Alert going past 9pm before either.
If it's more than a three hour event, I suspect many Powerwalls are going to hit the reserve way before the end. If ever there were a day to curtail the output, this would be it. I suspect they don't have that level of control at this point.
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