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Tesla Solar/Powerwall for Tank/Home Backup (1 Viewer)

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saltyanimals

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I was able to do this last night with my SmartThings after you reminded me that I wanted to do this.. =) It's painless with SmartThings as well and literally took about 20 mins. Most of that 20 mins was figuring out I had to download an IOS app that would generate the authentication token from Tesla since these devices can't actually connect to my gateway 2 directly, but rather to Tesla's servers. The original reason I went with SmartThings 8+ years ago was how open the platform can be if you know what you're doing. I'm glad it also supports the Tesla now. I just learned of Hubitat when you mentioned it, but not ready/need to switch platforms just yet with my current ecosystem investment in it. Just FYI that SmartThings can be used as well if anyone is already on it.

Just installed last night and I quickly set up some automations to power down general home switches, but will def play with it more later and think through what I could power down in my tank. My T5s come to mind as they're power hungry. ACs can be powered down by simply raising the set temp so probably no need to physically switch it. Pool control is however slightly tricky with a Pi connected directly to the pool controller, but does work to power down pumps since you can't simply plug into a high amp controlled switch.

Glad to see another Tesla PW user out there. Now I know of 3 reefers here with a system.
 
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foos

foos

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I was able to do this last night with my SmartThings after you reminded me that I wanted to do this.. =) It's painless with SmartThings as well and literally took about 20 mins. Most of that 20 mins was figuring out I had to download an IOS app that would generate the authentication token from Tesla since these devices can't actually connect to my gateway 2 directly, but rather to Tesla's servers. The original reason I went with SmartThings 8+ years ago was how open the platform can be if you know what you're doing. I'm glad it also supports the Tesla now. I just learned of Hubitat when you mentioned it, but not ready/need to switch platforms just yet with my current ecosystem investment in it. Just FYI that SmartThings can be used as well if anyone is already on it.

Just installed last night and I quickly set up some automations to power down general home switches, but will def play with it more later and think through what I could power down in my tank. My T5s come to mind as they're power hungry. ACs can be powered down by simply raising the set temp so probably no need to physically switch it. Pool control is however slightly tricky with a Pi connected directly to the pool controller, but does work to power down pumps since you can't simply plug into a high amp controlled switch.

Glad to see another Tesla PW user out there. Now I know of 3 reefers here with a system.
If you dig more you may find a driver that does local access. The driver that guy made for the hubitat authenticates locally and polls the api. I try to keep stuff as local as possible. Used to have wink and got so annoyed when things took forever or just did not work due to internet or wink being down. I think the only thing I have right now that is not local is voice that I do not use, and the thermostat.

How would you automate shutting down tanks stuff? I think I have enough solar and battery to not need to, 3x powerwall, but it would be nice to have it automated for low reserve power to be sure. I suppose I could find a relay that the hubitat can control and use that for one of the switch inputs on the apex and have that in my programming for lights and what have you.

Also, since you have had solar longer, did you find that the yellow pollen knocked production enough to justify cleaning the panels? I know my windows get caked in the stuff and I'm going to have to clean them yearly if I want to be able to see out of them.
 

saltyanimals

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I looked at Hubitat for a few mins this morning and it looks like that's one of the main differentiators being local. Interesting and tempting, but I'm also lazy to spend the time to swap ecosystems with the large number of devices I have on SmartThings. I literally have almost all wall switches on it except some closets. lol. Thanks for the bug in my head! I may do one day if I'm ever impacted by the local vs web.

Re: Apex integration. I saw the SmartThings handler for it on the ST forum so may give it a whirl. I wouldn't say it's necessary if you have enough panels or PWs to drive your demand. It's more of a power fail situation when I'm drawing only from house battery would I want to power the T5s down. Outside of the hander, could do a managed switch ontop of your apex outlet. May be just over engineering as I have the larger consumers to think about such as the pool, but we're all here geeking out. lol. I found myself really monitoring consumption during our freeze looking at every kW used and the tank > 600w.

Re: panel cleaning. I'm in a new construction and area so no mature trees to have pollen issues, but I have read that it would be min impact to production unless you're caked on. Hard rain keeps my panels clean and I've yet to see degradation issues. I only have 2 PWs on a 12k system. This is typically beyond my consumption and able to fully charge 2 PW plus sell on a clear day, but these summer high AC demands is proving differently. I'm also on the energy independent mind set so really trying to minimize buying from grid when I have perfectly charged batteries, however those batteries just don't get fully charged with 2 large ACs running on these peak hot days. I'm just waiting for the Telsa solar to car connector to come to market! Imagine using the car as additional batteries. Game changer. That's one of the reasons I didn't do more than 2 PW... either that will come out.. or PW prices will drop was my hope.
 
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foos

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I meant to ask about the freeze. Did you lose power? I did and had to use a 2kW generator to keep things running. I'm pretty sure if I had solar and powerwalls at the time I would not have had any issues. At the very least I would not have been sitting in a cold garage at 3am siphoning gas from my car....

I have a 12.24kW system with 3 powerwalls. I wanted 3 so that I could run everything I might have going without the grid. I have an electric dryer so that and the a.c. can draw 11kW. Having 15kW continuous would let me finish a load, keep the a.c. on, and even run the microwave. Idea is that with that, the standard sub 4hr outage will be a none event for me. Hell, I checked and I was on backup for 7 minutes yesterday, never noticed.

If Tesla does not allow vehicle to house, someone will. I know Elon said it will never happen since powerwall is for backup. I partially agree, powerwall should be the core of the system that is always there always waiting. I think we should be able to get a powerwall boost feature though. Let the powerwall call for power from a car, and it just feed back 5kW like it is solar, and the powerwall can worry about balancing everything. Keeps the car simple that way. Thought about signing up for twitter to tweet at him asking for powerwall boost, say I can siphon gas for a generator, let me siphon electrons for a powerwall. Either way, all someone needs to do is make a charger that can check the powerwall api, and if grid down and powerwall below x%, act like a solar inverter.
 
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foos

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Apparently I can't edit really old posts, So the first reserved for numbers from a big storm is going to just sit there saying reserved, mocking me.

Solar generation from 12kW array
9/10 65 kWh
9/11 60.4 kWh
9/12 51.2 kWh
9/13 20.2 kWh
9/14 12.9 kWh
9/15 29.7 kWh
9/16 39.9 kWh
9/17 52.0 kWh
9/18 55.4 kWh

Yes it dipped for the storm, but that is still enough to run 500W 24x7 and my usage dipped due to less cooling needed. According to the apex my tank is using 7kWh a day, so a little over half the lowest day. With the 40.5 kWh of battery backup I have, I would have had no issues running the tank and a room a.c. or chiller as well as critical things for me like the fridge. My a.c. is old and garbage, so I probably would have had to bump the temp up a few degrees even though it ran less anyway.

If you look at your bill and the 13-15th add up to 90kWh usage, with a 12kW array you would have needed about 27kWh of storage to run everything. Granted, time of use and time of generation could cause a gap in coverage on the third day so it is not that easy or guaranteed. So, in the case of 90kWh of usage over those three days and a 12kW array that generates the same amount as mine, two batteries would have probably been enough but you may have needed to conserve a bit to be sure and three batteries would have had you covered.
 
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