pdx_m3s
Active Member
Well you could probably fit 8 more on the East, North-East roof plane. And it looks like you have some south-facing roof availability as well.
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Newbie: 4kw + 1powerwall in progress
- Thread starter Wannaretire
- Start date
Well you could probably fit 8 more on the East, North-East roof plane. And it looks like you have some south-facing roof availability as well.
As a part of the process, they will do an onsite survey and see what you have and what sort of rewiring they need to do. As I understand it, if they need to split the load you end up with second load center (breaker panel) with backed up load only.
Just to be clear, it’s not so much ‘avoiding’ high consuming devices during an outage, but instead they simply won’t work. The rewiring mentioned is done to add a separate panel for all the low power devices that will be backed up by your Powerwall. The other things, AC, electric range, electric drier, etc will be left in the existing panel and those things will lose power when the power fails.
Basically you will pick a subset of your circuits that you want to provide backup power to in an outage and they will move those circuits to a new panel that will be backed up by the Powerwall.
charlesj
Active Member
I have a system almost 4kw, perhaps 3.95, essentially the same, and been getting 6.+ mWh consistently with late afternoon shading. And, we have that coastal fog issue at house.
I would think if he doesn't have shading issues and perhaps no fog issues, he would get closer to 6.5 -7 mWh.
roblab
Active Member
I often over generate, and PG&E pays me for it at true up.
My feeling is that you can always add more as you feel it's worth it. I am now at 11 kw solar with 3 powerwalls, and I'm not sorry. My zip is 94508, also in Northern Cal. I don't find it worth while to try to charge my cars on the power walls, so I just feed back to the grid. But if you're like me, there are power outages several times per year, (sometimes per month, sometimes for days) and you just feel you gotta do something. I'm willing to pay the ten bucks or so for connection to PG&E for the convenience, as in charging my cars one day and letting the grid get power for the next three or four.
Got it thanks. I have my on-site visit scheduled next week. I'm wondering if I have 2 powerwalls does it make it a 'simpler install if I dont need a seperate panel as you mention above?
Thanks. We've been able to avoid the rolling blackouts my just a few miles. But we still see outages for a few hours a couple of times a year. We've been lucky with the outages, doesn't necessarily mean we'll be lucky going forward...
One question I have is, how 'easy' is it to add a powerwall later if you already have one? Permits needed again? Major, or minor, labor given all the wiring is setup?
Thanks
I have same size PV and PW as you and I am in Sacramento area. Yes, I over generate too in some months. The goal is to make your true up bill ~$0. If your annual NEM charges are negative, PG&E does not writte you a check for that. If you over produce in terms of generate more than you use for the entire year, PG&E only pays you $.03/kWh. That is not worth the cost of the over capacity
I got this advise on another forum.
I'm sure it's legit but I don't know how to interpret this and communicate what I want/need with Tesla next week. Any thoughts on this? Thanks
As a certified Tesla installer who has designed numerous Powerwall systems I would suggest that you request your installer use a Gateway 2. This Gateway has a 12 slot internal panelboard option that can hold 3 full size 2 pole breakers or 6 Eaton Quad breakers. It can be configured to be either a unbacked up heavy load panel or an essential load panel.
I'm sure it's legit but I don't know how to interpret this and communicate what I want/need with Tesla next week. Any thoughts on this? Thanks
As a certified Tesla installer who has designed numerous Powerwall systems I would suggest that you request your installer use a Gateway 2. This Gateway has a 12 slot internal panelboard option that can hold 3 full size 2 pole breakers or 6 Eaton Quad breakers. It can be configured to be either a unbacked up heavy load panel or an essential load panel.
The gateway 2 is a new device in the US for tesla. The "gateway" is the "computer brain / device" that does all the power load switching. It determines which direction your power is flowing (solar to home, solar to grid, solar to powerwalls, powerall to home etc). Its simply a newer version of that device, with some additional capabilities than the one most of us have.
In effect, that recommendation is just to ask for the newest computer, as it were. Tesla would likely be using it in your install anyway since you dont have it scheduled as of yet, but it wouldnt hurt to ask.
On your "how easy is it to add powerwalls later" comment, you could request that tesla wire it for adding a powerwall later, but in general I think you would pay for the price of the powerwall plus at least 1k ish of labor. It could be significantly more as well.'
If, for example you get 1 powerwall, you absolutely can not backup your whole home. As was stated earlier, its not you "deciding not to use an item during a power outage" its you, "being completely unable to turn something on whether you want to or not" during a power outage because it simply isnt wired that way. 1 powerwall can only provide up to a 30amp circuit, so they WILL rewire and move any backed up circuits to a new panel, and leave anything that isnt backed up in your old one.
This means in general, you might have the circuits for your fridge, and regular wall outlets backed up, but not much else. That may be fine with you, but if you then later (next year lets say) decide you want to add a second powerwall, and backup more circuits, or "I was told 2 powerwalls would let me backup my whole house, so lets just buy that second one in a year or two", it would basically moving the other circuits.
Translation, the second powerwall in that instance would cost likely the price of ordering just one now, including the labor, or the price of the powerwall and another 3k in labor.
The cheapest its ever going to get to get additional powerrwalls is right now, bundled with the first one.
Now, if you ordered two, and then had whole home backup already, but asked them to wire it in case you wanted a third one,... that third one would not likely cause any rewiring so it would likely be price of powerwall + 1k of labor or so to install... because it wouldnt require any circuit moving, etc.
The TL ; DR version of "how easy is it to install powerwalls later" is .... " it depends on what you start with, and how your original install is wired, but it will never be as cheap as it is to do it on the first install. It just depends whether its "moderately" more, or "the same price as installing 1 powerwall new", depending on how many powerwalls you start with and the complexity of your install."
There is another thread about the gateway 2 here. It was recently released and right now it seems to be kind of a limbo time where some installs are getting gateway 1’s and some are getting gateway 2’s. The gateway 2 does have the internal panel option, which in some cases can eliminate one electrical panel that needs to be installed. If you have just recently ordered a system and are just in the design phase now it’s likely that they will give you a gateway 2 anyway. If you are further along in the process and have been permitted and have your install scheduled, then you may wind up with a gateway 1
charlesj
Active Member
I had that dilemma at one point and told myself that one PW was just too expensive installed as you can see the 2nd one is only 5k.
By the way, is that the new price on a PW, 5k uninstalled? Haven't looked lately.
From what I can gather its roughly $5k installed to add the 2nd powerwall. (Cash price). Not factoring the 26% fed rebate...
tesla charges less installation fee when installing 2 vs installing 1. the price for 1 also includes the gateway, and the permitting costs dont change from 1 to 2 either.
So installing 1 is 6500 (pw) + 1100 (gateway) + 500 (permits) + 3000 (installation).
Installing 2 is adding the additional 6500 for the second powerwall, and reducing the price of installation from 3000 to 2500. thats if you are just getting powerwalls with existing solar. If you are getting solar, I believe there is a bundle price discount which basically wipes out the labor charge (since they are already there doing the solar). I havent looked too closely into the solar + powerwall bundle pricing right now because I have existing solar but I believe thats whats going on.
Ours had this bundling discount.
There had a $2500 charge for installing 2 Powerwalls, and a $2575 credit for bundling the Powerwalls with the SolarRoof.
That is exactly what we had. As a note, when we were pricing it with 1, it was $3k install and I believe $1500 credit. So, at least with the pricing at the time with a solar roof, the 2nd PW really did come in at $5k, before the ITC and any other credits.
Quick update. Talked to my rep who helped me add 3 panels to my design (total: 15 panels). Makes me more comfortable/future proof with my current annual use around 7200 kwh. They are working on an updated quote/contract. I also dropped the powerwall. One pw just doesn't seem worth it. 2 too much $. Hope we continue to be lucky with the rolling power outages from pge.
I will continue to consider batteries/backup as prices and options get better next few years.
Site plan for permit is trow AM. Anything I should double check? Should be pretty straightforward with only panels being installed....thanks
I will continue to consider batteries/backup as prices and options get better next few years.
Site plan for permit is trow AM. Anything I should double check? Should be pretty straightforward with only panels being installed....thanks
