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Questions about Solar+Powerwall3+Two Model Ys

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We rarely get outages…but when we do, it's for awhile. So the PW for me - a huge expense - was worth it because it gives me the backup I need, but also the ability to manipulate our power usage from the grid to help lower costs. If I didn't have TOU today, I'd consider it an investment for the future when they do add it.
 
We rarely get outages…but when we do, it's for awhile. So the PW for me - a huge expense - was worth it because it gives me the backup I need, but also the ability to manipulate our power usage from the grid to help lower costs. If I didn't have TOU today, I'd consider it an investment for the future when they do add it.
Makes sense. I will be very interested to see how everything winds up in my case. I know i need to temper my expectations a bit because at first I was thinking this will 100% cover my electrical usage, but in reality, I now don't think that will be the case. It's strange that I cannot find whether the net metering that my utility (Atlantic City Electric) says they do is 1:1 or some other ratio. It is not mentioned on any of their website pages or brochures.

 
Had my site assessment today. Main thing that came out of my discussion with the assessor is that 4 Powerwall 3s may be tricky in my case for a few reasons.
This is where my meter is, and you can see there are windows across the entire back of the house (full size and basement) as well as an egress well to the basement in the middle. I was told PW3s cannot be stacked front to back if ground mounting and need to be 3 feet from any door/window to a conditioned area. There would barely be space for one PW3 between the windows on the left and likely would be too high to have any on the right. Since this is where the meter is, their preferred location might not be possible.

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The deck spans the entire rear of the house so that's out (needs spring cleanup)
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The other side of the house may be more ideal but would require long runs of wiring to the opposite side of the house. He said it is possible that they may go this route, but didn't really know.
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Interestingly, he told me they are no longer installing in garages. I found this a bit hard to believe, but he told me the designers he works with all told him that it was something that came down from corporate to do no additional garage installs.

Wondering if anyone else here has any thoughts?
 

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Technically, the Powerwalls don’t have to be attached to your existing structure. You could pour a concrete slab to support a concrete stub wall just taller than the Powerwalls and mount all 4, two on one side and two on the back side of the concrete wall. Short underground conduit tun to the meter area where the Gateway will be mounted. I have never heard of Tesla doing this kind of installation, but it has been done for larger custom installations.
 
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Technically, the Powerwalls don’t have to be attached to your existing structure. You could pour a concrete slab to support a concrete stub wall just taller than the Powerwalls and mount all 4, two on one side and two on the back side of the concrete wall. Short underground conduit tun to the meter area where the Gateway will be mounted. I have never heard of Tesla doing this kind of installation, but it has been done for larger custom installations.
Guess I should have mentioned that I have an HOA and this would definitely not fly. I’m very interested to see what the designers come up with.
 
Would the HOA approve a metal shed? Install the structure that I mentioned above and plop a prefab shed over it.
Possibly? It would need to be set back from the house and easements and all at proper distances though, so I'm not sure it would realistically work. The assessor did mention that I could potentially get a stand built and put trees around it. That would potentially fly, but it would likely come at a somewhat significant expense to me since it would need to sit on a concrete slab + stand price + trees. Was really hoping this would be a case where they install somewhere available at no extra cost. My house is not making that easy, though.
 
Interestingly, he told me they are no longer installing in garages. I found this a bit hard to believe, but he told me the designers he works with all told him that it was something that came down from corporate to do no additional garage installs.

Wondering if anyone else here has any thoughts?
Tesla Energy operates in markets, meaning that different rules fall in different markets. At least for ME in Colorado, I got mine in the garage. And yes, it was a long run - but I wanted it there. Most of the other installs I've seen in the past 2 months have also been in the garage here.
 
Even though it is a long length of wire, the space under the deck could also possibly be used. It appears to have enough height and would conceal the installation.
You can’t see it in the picture, but ground from the back of the deck to the house slopes upwards only leaving around 2-3 feet from the ground to the bottom of the deck at the house. From the end of the deck that you can see it’s about 8 feet tall, so it’s quite a slope downwards away from the house.
 
Tesla Energy operates in markets, meaning that different rules fall in different markets. At least for ME in Colorado, I got mine in the garage. And yes, it was a long run - but I wanted it there. Most of the other installs I've seen in the past 2 months have also been in the garage here.
I was told that 85%-90% of installs in the northeast are done outdoors and not in garage. It appears that the in my market specifically, there are very stringent code requirements for in-garage installs. That’s what the assessor said anyways. With that being said, I think with my home specifically, there may be no other choice. The assessor also told me if they have to install in a specific place due to no other choice, the cost associated with that install location that would normally be paid for choosing it would be waived. I’m sure extra labor/material cost will still apply though.
 
You can’t see it in the picture, but ground from the back of the deck to the house slopes upwards only leaving around 2-3 feet from the ground to the bottom of the deck at the house. From the end of the deck that you can see it’s about 8 feet tall, so it’s quite a slope downwards away from the house.
I could tell that was the situation from the picture. I stand by my assertion that it would be possible to put them there. Same idea as what I suggested earlier - pour a footing to support a concrete stub wall to support the Powerwalls. In this case, you would also want to put a retaining wall feature on the uphill side so that you don't get any runoff getting to the Powerwalls and the whole thing won't slide down the hill.
 
Got my detailed plan and plan set from Tesla today. One good thing is that they actually got me from 97% offset to 100% offset with less panels by shifting more panels onto the rear (southern facing) of the home's roof since their survey showed it was larger. They were able to remove 2 panels overall as part of this change. This was a win.

However, I was shocked to see they spec'd my system for 2 Powerwall+ and 2 Powerwall 2s with 2x 7.6kW AC inverters and 1x 5.7AC inverter.

This is contrary to what I was told a week ago the day of the site assessment where my project advisor and the site assessor both said at least 2 of my PW would be 3s and the remaining 2 would be either 3s or 2s. I asked at the time if PW3s and PW2s are compatible and project advisor said yes. The reason they gave at the time for it possibly being 2 PW3 and 2 PW2 was that some utilities do not allow the additional AC output of the disabled inverters of the 3rd and 4th PW3 to be removed from the total AC output consideration (even though they aren't used) and they have strict output limits for total AC output.

Based on our convo and design they came up with, It seems to me that PW3 are not actually compatible with PW2 or PW2+. I asked if my specific utility would not allow 4x PW3 and that's why they made them all 2s? He said no, that isn't the case with my utility and this decision right now is more-so because Tesla may not want to provide PW3s where inverters are not used for financial reasons. This makes no sense to me. Why would they allow config with 4x PW3 then since its very unlikely non VPP setups will need 46AC output (4x PW3 AC inverter).

The advisor also told me (incorrectly) that the only difference between PW3 and PW2 is that PW2 does not have same starting power for AC units etc. as PW3 but everything else is the same. Said it's not an issue for me since I will be having 4 PW2 (which is true) and they will have more than enough power to start the AC unit and any other item with high initial peak V needed. I explained that this was not the only difference (and not even the largest or even relevant in my case since I have 4 PW). The biggest difference for me is continuous kW output per PW where it is 5kwH for the PW2 and 11.5kWh for PW3. I explained this is a huge difference in terms of supply to my home! Just my 2 Model Ys would use 22+ kWh if they are both charging at full speed. Not sure if the advisor did not know this, or was ignorant to the facts, but considering the more than double continuous output per PW is a huge selling point of the PW3, its hard to believe he wouldn't know.
 

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