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Powerwall 2 without solar. Is it worth the cost?

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Through referrals I have the option of getting a Powerwall 2. Solar is not really an option for me. Lots of trees around house and minimal exposed roof with sun exposure. (Live in pacific north west) Does anyone have a Powerwall without solar? How has it helped you? How long does it last if the power goes out? How much did it cost you to install? Any input would be appreciated.
 
I have two Powerwalls without solar installed on Sept 13th.

(1) That really depends on how many Powerwalls you need. I went with whole home backup and my average consumption is 14, so I went with two Powerwalls. Using math alone, I can go almost 2 days of regular use with my setup.

(2) $13800 was my final cost for two Powerwalls + install. I did not need any electrical upgrades as my house was new with a 200 amp service, and a 200 main breaker.

(3) I do my own Time of Use Load Shifting right now because PowerwallOS 2.0 is still in development which will let me do it automatically. This means that I take my house off the grid at 6am and use the Powerwalls, and then put it on the grid at 11pm. the reason is that I charge my Powerwalls alone with my Model S and Model X between 11pm and 6am because electricity is nearly 4 times cheaper based on my rate plan (PG&E's EV-A Rate Plan). I use power from the Powerwall when rates are around $0.46.

Note: When Tesla comes onsite, they will help you engineer your solution based on your current electricity load. Note, you don't have to do Whole Home Backup, you can be selective if you want if you just want a single Powerwalls.
 
If you have the right to get a free PW2 installed, and you have ultra cheap "EV" off off peak electricity rates (say around 1/3 of peak rates) then you have every incentive to install your PW2 and set it to buy electricity in that off off peak rate, and discharge in more expensive periods.
And you still keep the ability to set a reserve power level so you still have electricity if the grid goes down. 2 or 3kWh can be enough to power your lights, a few fans and your electronics for several hours.
In the end it *might* save you the whole price of the PW2 while giving you the value of a house wide partial UPS.

Think about how many times you lost power over the last decade. How much would it be worth for you to have minimal electricity for 24 hours (if you set reserve levels a little higher) ?
 
Problem I perceive with this is that you need the power cut to start when the PowerWalls are fully charged ...

... most of our power cuts here are either momentary (lightning nearby and something upstream trips and almost immediately power is restored, but all electronic gear and all the clocks in the house "die" during that interval).

The other type is some twit in a mechanical digger going through a cable, or an elderly tree just decided today is the day to keel over ... that is all sorted out within a couple of hours, so even a largely discharged Powerwall would usually do me for that situation.

Beyond that is a once or twice a decade storm, and because we are rural it might be a day or two before we are back on. For that I have a generator, only large enough to power essential circuits, but if we had some sunshine (storms normally in Winter and not much PV power at this latitude in Winter), and a powerwall which I could recharge from generator, then running the generator 24/7 would mean that PowerWall gained some during the night when we had everything turned off, gained a bit more from PV during the day, and then I would have more than just generator on its own for evening lighting and TV etc.

But Powerwall not yet easily recharged from Generator, and not sure about from PV if the Grid is off. We do have isolator switch for the grid (so I can run the Generator without back-feeding the grid), and I believe that once the generator is running the PV will also work ... but not certain that everything will play well together.

I keep meaning to buy a bigger generator ... and we keep not having a once-a-decade storm ... although when we do it will catch me out of course :oops:

The one thing I wish I had done when we rewired the house was to put all the essential circuits on a single board, so we could easily isolate all the other power-hungry junk, and only consume survival electron-rations without all sorts of mucking about trying to figure out what ELSE was soaking up power and needed turning off.

Past storms have been "trail an extension lead through an open window to run the TV and a couple of lights" which is a long way short of ideal!
 
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