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Yes, that is what makes my system work even though I do not have the true Southern exposure and not a big solar system. Right now my peak is 1 to 7pm and of course the power company is slowly changing that and moving peak to later in the day. If I lose that afternoon peak my bill will increase which is what they want.
 
Exactly. My "peak" is not a real "peak" according to one powerwall person I talked to. Whatever. I'm thrilled with them so far. The idea of exporting all solar to grid during peak makes no sense. I'm guessing in CA maybe you make a lot of money for exported power during peak time?

Yep, in California (PG&E, EV-A) peak price is almost 4x the price of off-peak. By exporting all solar production during peak, you get plenty of credits to cover grid usage during off-peak and even partial-peak.
 
The idea of exporting all solar to grid during peak makes no sense. I'm guessing in CA maybe you make a lot of money for exported power during peak time?

To expand on @gnumeric's comment: with Net Energy Metering (NEM), you can use credits you earn for exporting to offset your bill. If you export at $.40 and use at $.13, you can use 3 kWh for every kWh you export. This is how an 80% offset in kWh ends up as a 100% offset in dollars out here. This means you want to export whatever you can during peak.
 
Wow! Well here in TX there are no rewards for exporting solar to the grid. I used to get .07 cents/kwh, but no more. There are other plans but the free nights deal is the best I can do. Why don't they want us to charge our batteries at night? If everyone had batteries, and everyone charged them at night, they'd have no "peak" load in the day. They could totally smooth out their production and save tons of money. I guess somehow they'd lose money, not being able to charge peak rates if there were no peak. Whatever the answer, it has to do with the utilities making money. But it sure seems like the best scenario is all homes have batteries and use it during the day to run their AC, and let the utility have flat demand (more flat, anyway).
 
Why don't they want us to charge our batteries at night? If everyone had batteries, and everyone charged them at night, they'd have no "peak" load in the day. They could totally smooth out their production and save tons of money.
Utilities and regulators tend to be usually behind the curve. Primary reasons given is they don't want people arbitraging night-time rates into daytime.

I think that's BS especially if export-restrictions are adhered to and easily checked (albeit with more Utility work). Other large battery OEMs (LG Chem, Sonnen, etc) don't have such restrictions on grid-charging in their standard installations, Some even advertise they can also grid-export.

Other reasons is grid-charging is extra-load on the grid Utilities are not prepared for, or other related reasons. All BS if they're supporting EV charging.
 
I see - now. I didn't before because in TX we don't get big money for exported solar. That's fascinating that other battery companies don't restrict grid charging.

Why, if you know, does Tesla not give me a simple way to tell my own batteries when they are allowed to discharge, or not discharge? I'm mystified why my powerwall will sometimes just discharge a few kwh to the grid for no reason, in the middle of the night or in the middle of the day. It happens when the battery is not full, so its not because there is no where else to put my solar. Its just bizarre. I just don't get it. I have the feeling if Tesla told me I'd be angry, as I think its to fulfill some "higher purpose" at my expense. The energy stored in my batteries came at great cost to me financially. It sure seems like I'd get the choice when I use it.
 
I see - now. I didn't before because in TX we don't get big money for exported solar. That's fascinating that other battery companies don't restrict grid charging.

Why, if you know, does Tesla not give me a simple way to tell my own batteries when they are allowed to discharge, or not discharge? I'm mystified why my powerwall will sometimes just discharge a few kwh to the grid for no reason, in the middle of the night or in the middle of the day. It happens when the battery is not full, so its not because there is no where else to put my solar. Its just bizarre. I just don't get it. I have the feeling if Tesla told me I'd be angry, as I think its to fulfill some "higher purpose" at my expense. The energy stored in my batteries came at great cost to me financially. It sure seems like I'd get the choice when I use it.

How much, in kWh, is exported by the PW to the Grid without your consent - and how do you know/capture the event?

I thought that PW in the US are not allowed to export to the Grid.

Edit:

I guess PW export to grid is allowed in some states: Tesla Just Enabled a Clean Energy ‘Virtual Power Plant’ in 2 States | Inverse
 
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How much, in kWh, is exported by the PW to the Grid without your consent - and how do you know/capture the event?

I thought that PW in the US are not allowed to export to the Grid.

Edit:

I guess PW export to grid is allowed in some states: Tesla Just Enabled a Clean Energy ‘Virtual Power Plant’ in 2 States | Inverse


How much is export by the PW - answer is very little. Its just weird that it happens at all. I can tell by looking at my phone app. It shows how much my house is using, how much is coming out of the powerwall, how much from solar, and how much from the grid. If the powerwall is discharging 3kw for example, and the house is using 600 watts (about my resting rate without AC or anything big running), then that power is going to the grid. The grid line in the app shows power going to the grid, instead of coming from the grid. I looked and right now the app shows no power exported from the pw to the grid today or yesterday. But for the last 3 days it has rained hard in Houston, with very little sun. At this moment my PWs are flat, sitting at the reserve % of 6% where I have it set.

Even when it happens, its just a kwh or so. Its not like it ever completely discharged itself to the grid. I'm just surprised it does it at all. And I don't like it and am not happy about it, even though its a small amount. That's very expensive energy. I bought the PWs specifically to take advantage of my solar panels and keep the solar they produce for my own use, since I get nothing for it from the utility (thanks Texas).

The next time we get some sun and my PWs do their export to the grid trick, I'll screen shot it and post.
 
If it's like my system, I think it's just the nature of the PW's inverter lagging the actual house demand changes. So if the house load suddenly increases, some grid energy is used as the Powerwall(s) ramp-up their output, and similarly if the house load suddenly decreases, some energy goes back out to the grid until the PWs ramp-down. So the grid basically acts as the shock-absorber for the quick house fluctuations, even if they're tiny. It likely all averages-out in the end, though on my system at least the "average" isn't truly 0 but around 20W drawn from the grid, so over the course of a day there's still ~0.2kWh seen by my meter overnight even though my PW banks all the energy my house needs for a night. But the Gateway UI sometimes shows some power going to or coming from the grid, and the REST API that I poll every ~2s constantly shows some positive or negative grid power value, I think the UI only lights up the grid path when this value is above a certain number (~0.1kW I think). In my case none of it is big enough to register visually on the Tesla app, though it does show the ~0.2kWh grid consumption every day.
 
OK, I see the same thing happen too. My house load draws some from the grid, or the Powerwall exports to the grid - briefly, when there is surge in demand. Never a sustained export from PW to grid.

Just like what Woferry describes, I see this rare short export to the grid when there is sudden change in home demand - like when I start charging my EV while two AC compressors are on, but one of the compressor turns off.

I guess its a way to stabilize the system.
 
The sky is still overcast in Houston today, but I'm getting a little power from my panels, and guess what!!??? I'm exporting it to the grid, despite my powerwalls being at 6%, the reserve level I set. Pisses me off. But it only lasts a short time. I do not buy the shock absorber theory, just because it lasts too long. There's no reason it should take more than a few seconds at most for the powerwall to switch to banking the power in my battery rather than spitting it out to the grid. Here's a pic for the doubting thomas's...
exporting.PNG
 
I'm very happy with the powerwalls, in case I've confused anybody with my complaints. Just because I want changes to the app and user controls doesn't mean I don't love them. Here's a video just for fun.

(sorry, I said they used 8 ga wire but I looked at a pic I took during install and it was 10 ga)

 
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If it's like my system, I think it's just the nature of the PW's inverter lagging the actual house demand changes. So if the house load suddenly increases, some grid energy is used as the Powerwall(s) ramp-up their output, and similarly if the house load suddenly decreases, some energy goes back out to the grid until the PWs ramp-down. So the grid basically acts as the shock-absorber for the quick house fluctuations, even if they're tiny. It likely all averages-out in the end, though on my system at least the "average" isn't truly 0 but around 20W drawn from the grid, so over the course of a day there's still ~0.2kWh seen by my meter overnight even though my PW banks all the energy my house needs for a night. But the Gateway UI sometimes shows some power going to or coming from the grid, and the REST API that I poll every ~2s constantly shows some positive or negative grid power value, I think the UI only lights up the grid path when this value is above a certain number (~0.1kW I think). In my case none of it is big enough to register visually on the Tesla app, though it does show the ~0.2kWh grid consumption every day.

I started a thread here a few days ago regarding this very "issue" (not sure if it is even an issue):

Odd, Persistant Grid Draws in Self Powered Mode.

My setup is still new, but I do see persistent .1 kW to .3 kW draws from the grid throughout the day, even though solar/PW is supplying more than enough juice for the house. There is a little draw to the grid, but the daily average total is around 1.5 kWh draw and .3 kWh output to grid. This seems excessive, at least for my setup. I am waiting for Tesla's tier 2 support to get back to me regarding this.

IMG_3080.PNG
 
The sky is still overcast in Houston today, but I'm getting a little power from my panels, and guess what!!??? I'm exporting it to the grid, despite my powerwalls being at 6%, the reserve level I set. Pisses me off. But it only lasts a short time. I do not buy the shock absorber theory, just because it lasts too long. There's no reason it should take more than a few seconds at most for the powerwall to switch to banking the power in my battery rather than spitting it out to the grid. Here's a pic for the doubting thomas's... View attachment 424976
You're still TBC all-day-peak right?

Try switching to Self-Powered.
 
If I use Self-Powered, it will discharge at night after 9pm if there's any charge left in the battery by that time. I do not want that. Right now TBC is working, with the small issue of randomly discharging from the powerwall to the grid. But its only discharging a small amount of power, nothing to worry about other than its inexplicable and frustrating.
 
If I use Self-Powered, it will discharge at night after 9pm if there's any charge left in the battery by that time. I do not want that. Right now TBC is working, with the small issue of randomly discharging from the powerwall to the grid. But its only discharging a small amount of power, nothing to worry about other than its inexplicable and frustrating.
No, I'm posing a test where you manage when you're on self-powered vs TBC, inception.

If self-powered behaves better for your solar hours than TBC's, there's something wrong with TBC. Then, you could try managing the mode yourself (via the app at certain times of the day) while you report the issue to Tesla.

I'm currently test-using the "owner-api vs install-api" to automate (via my app) switching between self-powered and automated -- inception -- because self-consumption has less weird blips, for me, than automated while trying to match home-usage vs solar.
 
If I use Self-Powered, it will discharge at night after 9pm if there's any charge left in the battery by that time. I do not want that. Right now TBC is working, with the small issue of randomly discharging from the powerwall to the grid. But its only discharging a small amount of power, nothing to worry about other than its inexplicable and frustrating.

Totally with you on that frustration. On days when my Solar/PW more than makes up for home consumption, I'm still show 94% "self powered". There is no reason why it shouldn't be 100%. Still waiting for my call back.