Good to know. I've just set my PW to 100% and drop it back down to the event. My PW always export at max so doesn't take very long to drain line.
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Tesla Virtual Power Plant in CA
- Thread starter power.saver
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Thanks for this info. This is the exact behavior I'm seeing.
I assume my PTO export is limited because of my line size. I looked at upgrading my panel from 150A but because my lines are underground and I live in a flag lot, the cost of trenching and replacing was prohibitive.
It is more about accounting than a physical limitation, so upgrading your PG&E service won't change your export limit. The value is set from your solar invertor and then entered into the grid database to ensure that local transformers aren't overloaded and damaged. Say you have 10 neighbors on 50kW transformer. Your system can send back 6.2kW which then leaves 43.8kW available for your neighbors to install solar. Another neighbor installs a system capable of 11kW and that leaves 32.8kW for the other 8 neighbors and so forth. Eventually PG&E would tell one of your neighbors that can install solar or only so much solar unless they wanted to pay for a transformer upgrade.
Really good info... thanks.
I'm wondering if sizing of my system had something to do with it -- you mention size of the inverter, and the 5.2kW limit is slightly higher than my solar setup.
These extreme hot days has been pretty interesting. It was cloudy yesterday as well so with heavy A/C demand, seems like a bad situation if one were to lose power and the grid is down if one wanted A/C on (not a surprise and we all knew how far batteries will really last (like not long at all)). Does anyone know how long a decently sized home generator can run for and is anyone thinking of solutions/ways of dealing with extreme heat, off grid, longer term grid outage?
I remember reading about datacenters using special A/Cs that freeze ice during the day and have air blown over ice for cooling when the sun doesn't shine anymore. There are whole house fans, but those are less useful when it's still 80 out at night. Are variable, multi stage A/Cs a lot more energy efficient? I notice my single stage AC pulls like 3.5-4kW normally and I don't have enough roof space to really put more panels at this point.
I'm not on VPP (being on Enphase batteries) and I can't even get through peak currently with the high heat and still have a decently reserve. I'd probably hit my reserve in an hour if I were on it.
I was micromanaging my reserve yesterday and was pulling from the grid all day (set reserve at 100%) so I can be at full (from the mixed sun) before 4pm. My consumption hit an all time high (for me) of 75kWh+ yesterday when we are 15-20kWh in the winter (maybe ~35kWh normally in summer pre-solar).
Just curious if more folks are thinking of other things in the toolbox like hybrid water heaters or have other things they can share/thinking about. I assume this type of weather will be the norm for a long while.
I remember reading about datacenters using special A/Cs that freeze ice during the day and have air blown over ice for cooling when the sun doesn't shine anymore. There are whole house fans, but those are less useful when it's still 80 out at night. Are variable, multi stage A/Cs a lot more energy efficient? I notice my single stage AC pulls like 3.5-4kW normally and I don't have enough roof space to really put more panels at this point.
I'm not on VPP (being on Enphase batteries) and I can't even get through peak currently with the high heat and still have a decently reserve. I'd probably hit my reserve in an hour if I were on it.
I was micromanaging my reserve yesterday and was pulling from the grid all day (set reserve at 100%) so I can be at full (from the mixed sun) before 4pm. My consumption hit an all time high (for me) of 75kWh+ yesterday when we are 15-20kWh in the winter (maybe ~35kWh normally in summer pre-solar).
Just curious if more folks are thinking of other things in the toolbox like hybrid water heaters or have other things they can share/thinking about. I assume this type of weather will be the norm for a long while.
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After my install my home has gone fully electric with hybrid water heater and induction cooktop.
Surprisingly my energy usage was fairly stable yesterday despite the near record heat, I think it just speaks to how efficient mini splits are. I had mine installed recently.
I love my mini splits. I have a whole bunch running set at 70 and 68 degrees. Heat wave, what heat wave?
feelin' bad about it but i've set my reserve to 100% today. i feel like either today or tomorrow the grid could go down. ISO is predicting 48GW peak today and 51GW peak tomorrow. those have got to be records? maybe it will be OK but if too many people think like me that (admittedly small) VPP buffer won't be as big today.
If you have batteries like Powerwalls, you can elect to take EV2-A without an EV.
This is the EV2 Tariff. The battery eligibility has been in effect since July 1, 2019.
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51GW would definitely be a new record. I can't remember if any of these highs caused rolling blackouts, but I'm on a block 50 which theoretically wouldn't be impacted.
Yeah I think overloading a transformer or something is always a possibility, that's why I've also been debating if risking my PW capacity is worth the money. Having never had a long outage makes me usually lean to setting my reserve lower.
My PW don't back up my AC, so may as well discharge and support the grid. If outage happens then I don't need much for just my fridges
My recommendation would be to add a mini-split or a window air conditioner in the rooms that are most important to you. Perhaps the master bedroom and the living room? That way you can still have a comfortable place without having to run the central air conditioner(s).
I'm not in California, but I figured it might be worth sharing what I do in our 1,200 square foot 3-bed home in Northern Virginia. I'm on a time-of-use plan with demand charges (Dominion Schedule 1S). Hot water, cooking and heat are natural gas. I cool the house to 67F overnight during off-peak hours using our 2-ton central air conditioner. During peak, I only run an 8,000 BTU window air conditioner that's in the center of our home (open plan dining, kitchen and living room). This keeps our main living area comfortable and keeps the bedrooms from getting too hot. The back bedroom usually gets up to 77F by the end of the peak period, which is a couple of hours before we go to bed. Peak runs from 11am - 10pm during the summer.
Right now, in California, I see recommendations to "pre-cool" your house to 72F during off-peak and solar hours. It would be far more effective to cool your house to below 70F - basically as cool as you can stand it - during peak solar production. The important thing is to cool the core of the house - the furniture, the interior walls, etc., so they can act as thermal batteries to carry you through peak time. Give it a shot tonight and tomorrow and see how it goes. Tomorrow looks pretty rough on the CAISO forecast.
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