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New Powerwall Advanced Options [Toggles for charging from and discharging to grid from powerwalls]

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TED5000 on the Model Y Wall connector circuit (which is outside of my PW's purview.
You can fix this: Have Tesla add a CT to this circuit and bundle it with the house CT.

I have it this way and the PWs will feed the charger too (only when grid connected). Ask me how I know. (because I screwed up the other day and forgot to reset my charger to timed charge after a trip. The car immediately started charging when I put the cable on and I did not notice. The damage was only about $7).
 
just noticed the grid charging option, but I'm SCE NEM2, so maybe I'm missing something here regarding arbitrage. I see folks mentioning getting $14k back from selling back power (though they seem to be PG&E)

It seems like SCE has it stacked against me utilizing grid charging to 'make money' (though I can get close to 'break even') because my off-peak $0.33/kWh, peak $0.52/kWh. So yes, if I suck power off-peak and push back power during peak, I 'seem' to gain $0.21/kWh. This is ignoring the not bypassable charge (NBC) of something like $0.03 for pulling from grid, so it's actually $0.18kWh of credit.

However, that's still not actually what I get, since at the end of the service year annual Tru-Up, they take all my credit away and give me around $0.02kWh back as a net producer (barely cancelling the NBC if I was importing to export)

So at most, grid-charging would let me maintain a closer-to-$0 but never 'make a killing' in the thousands of dollar range. (I only have 2 PW, and an 8.4kW system)

Oh, and this is not including the base $12/month charge of just being a customer that I have to pay up front.

So... am I missing something / some setting that would get me to keep the $400-odd overproduction fully?

Edit: to use the proper lingo.
Edit: FWIW, my first tru-up took my ~$400 credit from solar+PW and changed it to a $70 credit on my actual bill, which the $12/month draws from.
 
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I have it this way and the PWs will feed the charger too (only when grid connected)
When I was getting ready for the car (on a long, long waiting list), I went ahead and installed the car's Wall Connector. Then, the day before delivery, Musk announced a free year of Super Charging. Cool, but free was hard to pass up, so for a year I missed out on home charging, one of the biggest EV benefits, poor me.

But back then I was thinking of getting a second meter to charge the car one the cheaper still EV-B rate. Besides, charging the car off of the PW seems silly. So we connected the charger on the grid side of the PW. Then it turned out there are extra monthly fees for a second meter, and "aggregating" two meters messes up the NEM credits, big time.

In the end I am glad to have it where it is. If we ever do need to charge the car off of solar during a prolonged outage, PW of course can keep the solar running, and I can plug the car into the dryer outlet. And wait patiently.

Living as we do about a mile from, and on the wrong side of the Hayward Fault, we do think about these things. We also hung onto our little 2kW propane generator in case the big shake comes during winter weather.

SW
 
just noticed the grid charging option, but I'm SCE NEM2, so maybe I'm missing something here regarding arbitrage. I see folks mentioning getting $14k back from selling back power (though they seem to be PG&E)

It seems like SCE has it stacked against me utilizing grid charging to 'make money' (though I can get close to 'break even') because my off-peak $0.33/kWh, peak $0.52/kWh. So yes, if I suck power off-peak and push back power during peak, I 'seem' to gain $0.21/kWh. This is ignoring the not bypassable charge (NBC) of something like $0.03 for pulling from grid, so it's actually $0.18kWh of credit.

However, that's still not actually what I get, since at the end of the service year annual Tru-Up, they take all my credit away and give me around $0.02kWh back as a net producer (barely cancelling the NBC if I was importing to export)

So at most, grid-charging would let me maintain a closer-to-$0 but never 'make a killing' in the thousands of dollar range. (I only have 2 PW, and an 8.4kW system)

Oh, and this is not including the base $12/month charge of just being a customer that I have to pay up front.

So... am I missing something / some setting that would get me to keep the $400-odd overproduction fully?

Edit: to use the proper lingo.
Edit: FWIW, my first tru-up took my ~$400 credit from solar+PW and changed it to a $70 credit on my actual bill, which the $12/month draws from.
You have to be a net consumer of kWh and owe the utility money at true-up in order to make use of the TOU arbitrage credits. Since you said that they took away your $400 credit and replaced it with a $70 credit, you must be a net surplus generator. That's just how it works.

I really do save the money with arbitrage because I still owe PG&E $1,000+ at true-up.
 
West of the fault, between 580 and Skyline Blvd. further west is rugged land out to Dublin.

580 is pretty much on the fault, so when the fault rips, 580 underpasses will probably be impassible. Hiking out north, west and south are all problematic. So we may be stuck for days.

SW
Well, it seems like you have it all checked out. It looks like the actual shaking will be worse west of you, but for me, I do start by thinking of the distance to the fault, which really isn't the optimal way to think of it. Actually shake hazard, and escape routes are important factors.
If you want sleepless nights, here is the local hazard viewer, actually surprising how many faults can impact any one place;

All the best,

BG
 
West of the fault, between 580 and Skyline Blvd. further west is rugged land out to Dublin.

580 is pretty much on the fault, so when the fault rips, 580 underpasses will probably be impassible. Hiking out north, west and south are all problematic. So we may be stuck for days.

SW
Don't plan on going SE on 680 also. The Calaveras fault is there. It runs from Danville to Hollister.
 
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I haven’t seen answer on this yet. I received the federal investment tax credit for my Powerwall in 2017, which specified that it be charged 100% from my solar panels. Does anyone know what the legal/tax position is re grid charging 5 years later? The FITC documentation was rather light on details. Thanks!
 
I haven’t seen answer on this yet. I received the federal investment tax credit for my Powerwall in 2017, which specified that it be charged 100% from my solar panels. Does anyone know what the legal/tax position is re grid charging 5 years later? The FITC documentation was rather light on details. Thanks!
My understanding is that once you have reached the 5 years, you can charge from the grid now, this is not advice.

Check with a Tax professional before changing your charging behavior.
 
I haven’t seen answer on this yet. I received the federal investment tax credit for my Powerwall in 2017, which specified that it be charged 100% from my solar panels. Does anyone know what the legal/tax position is re grid charging 5 years later? The FITC documentation was rather light on details. Thanks!
WIth the caveat that I am not a lawyer so I can't be 100% certain this applies, Investment Tax Credits generally have a recapture period of 5 years (Instructions for Form 4255 (12/2018) | Internal Revenue Service, 26 U.S. Code § 50 - Other special rules). My assumption is that it's ok to charge from the grid after five years have elapsed given that the solar credit is an Investment Tax Credit.
 
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The concern with the above reference is that Section 50 refers to "investment credit property" which it defines as property eligible for a credit under this subpart. Section 50 is in subpart E, which deals with the business ITC. While the residential ITC is in section 25D, which is subpart A.

So it's not clear to me that the business ITC recapture rules would apply to the residential ITC.

Cheers, Wayne
 
Elsewhere on TMC someone is selling two Founders Powerwall 2s. He says he hasn't taken the ITC on these because he didn't know that was possible, so he's selling them saying the buyer can still take the ITC on these units. But are the ITCs based on specific units? I mean, say I had two powerwalls and took the ITC, then five years later sold them, couldn't the buyer then also take ITCs on the price they paid? Or does it really work like the one-time the tax credit for EVs -- only once per unit when sold as new?
 
The concern with the above reference is that Section 50 refers to "investment credit property" which it defines as property eligible for a credit under this subpart. Section 50 is in subpart E, which deals with the business ITC. While the residential ITC is in section 25D, which is subpart A.

So it's not clear to me that the business ITC recapture rules would apply to the residential ITC.

Cheers, Wayne
I think this is a valid concern. I wasn't able to find any reference to recapture with respect to personal credits, though. I think the three likely scenarios are either that personal recapture works the same as business, that there is no limit to the recapture period, or that there is no recapture. I'm choosing the middle ground between the two extremes. I suspect in practice this may not be settled unless they discover that a battery is being charged from the grid during an audit.
 
I think this is a valid concern.
FWIW, there's this private letter ruling regarding adding storage to residential PV: https://www.irs.gov/pub/irs-wd/201809003.pdf

It doesn't address recapture, but does apply a different standard to ESS for the residential ITC, vs the standard for business ITC: 100% solar charging vs a prorated ITC down to a 75% cliff, evaluated in each of the 5 years of the recapture period.

Cheers, Wayne
 
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FWIW, there's this private letter ruling regarding adding storage to residential PV: https://www.irs.gov/pub/irs-wd/201809003.pdf

It doesn't address recapture, but does apply a different standard to ESS for the residential ITC, vs the standard for business ITC: 100% solar charging vs a prorated ITC down to a 75% cliff, evaluated in each of the 5 years of the recapture period.

Cheers, Wayne
Yep. What I find interesting is how they try to infer intent from omission in the code:
Thus, the Congress purposefully chose to include a 50 percent usage requirement in the definition of “qualified solar water heating property”, but the Congress did not include such language in the definition of “qualified solar electric property.” This demonstrates that the Congress expects the energy used by a “qualified solar electric property expenditure” to be derived solely from the sun.
I wonder if similar logic could be used to say that because Congress included discussion of recapture related to business credits under § 50, but omitted it for personal credits, they did not intend to have a recapture mechanism for personal credits.

Bottom line, I think there's enough uncertainty that people should do their own due diligence on deciding what risks are acceptable with respect to the tax implications of turning on grid charging.
 
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Yep. What I find interesting is how they try to infer intent from omission in the code:

I wonder if similar logic could be used to say that because Congress included discussion of recapture related to business credits under § 50, but omitted it for personal credits, they did not intend to have a recapture mechanism for personal credits.

Bottom line, I think there's enough uncertainty that people should do their own due diligence on deciding what risks are acceptable with respect to the tax implications of turning on grid charging.
I put in 2 Powerwalls that I didn't take the ITC on but I put in a 3rd Powerwall that I plan on taking the ITC for. I'm going to assume that if I don't charge them using the grid any more than 66% of the capacity (you can't charge them separately) averaged over a year that I'm meeting the spirit of the requirement. I talked to a tax expert about this and I didn't get the feeling his guess was any better than my guess.