powerwall2 behavior when paired with solar

[Mike90250]

5 full days, and the power is back in town. I never lost it, being off grid. did have to scramble a bit with the milk situation. with nightime temps in the upper 20's and no power, lots of folks with no heat, or hot water

[astroboy]

yes - sorry to hear that, mike... it's a terrible experience. psychologically all of this is really hard. hopefully PGE is working on getting the power back on now that the winds have died down.

[JSchnee21]

Wow. Sorry to hear that Mike. Best wishes to you and the others impacted. We lost power for 10 days during Sandy. The lack of gasoline (no power to run stations, no power to run refinery, too many downed trees for delivery trucks and cars to reach stations) was by far the biggest issue. After a few days many folks just tried to leave and escape to PA, etc. But all of the downed trees, flooding, etc. made that difficult. Plus folks were afraid to drive too much and use up what gas they had for fear of not being able to get more.

[Mike90250]

For my town, the PSPS started Saturday 26th 5:30pm.
Gas stations and grocery stores are down. City water & sewer running on backup generators. All of Mendocino County is offline. Most of the cell towers are in remote locations and after today (72hours) may be getting ready to run out of fuel. A couple business had backup generators in place, but about 25% are now offline, mostly mechanical failure, and one was stolen and towed away. We are looking at Thursday 31st AM as the first reasonable expectation to start getting power back. That will be 120 hours (5 days) and well into a maintenance cycle for generators having been run 24/7
No refrigerated goods at all.
Safeway is selling dry goods off the shelf by flashlight and cash only.
Costco in Ukiah brought in a generator to run the gas pumps 24/7 to the general public, but it failed after 20 hours, and a replacement is in the works.

Late this afternoon, smoke started arriving, which will impact my solar harvest tomorrow.

[astroboy]

too many replies to quote them all but -
JSchnee21: same water heater; the controller is indeed very finicky. from reading scrambler's post i think maybe i just need to ground the inverter to the bolt, however, i'm not sure this inverter has a ground lug. i have a much higher quality one on order, so maybe that has the right connections. as for your other tips as it turns out i have everything you have mentioned. i did use my spare UPS to charge things during the night, and then i found out that it would not charge from the generator. this may have had to do with grounding as well. regardless we were able to charge our stuff during the day using the generator but it requires breaking decades-long habits ("oh i can charge this phone overnight...")

as for the house, if no one is home (like on vacation) with just the refrigerator running and a subset of the computers, the house uses ~10kwh per day. i'm sure we could reduce that further. in theory then a single powerwall could keep us going for a day. at the winter solstice, assuming there is sunlight, my PV system will produce about 13kwh. so in the absence of clouds the PW would keep us going indefinitely. in practice we'd probably crap out eventually. my plan was for 2 powerwalls to get more current, and hopefully these PSPS things only happen in autumn when the system makes about 20kwh per day.

i have all of my network on UPS backup and when the power went out comcast's head end failed immediately. it's still down 12+h after power was restored. my ancient DSL backup stayed up during the outage but my UPSs are not big enough to run for more than a couple of hours, so we had to use our cellphones for internet access. they did work throughout, maybe because just down the hill the power was on and so parts of the cell network were still operating normally. i did hear that up in marin after a couple days many cell towers started dropping out.

as far as tesla goes, i don't know if "affected by wildfires" means "affected by PSPS" but who knows, maybe they'll knock 1k off my order. i'm not expecting them to get to it until 1Q2020 or maybe later.

[scrambler]

How many kWh do you typically use per day? Can two or three PowerWall2 sized batteries (or similar) really cover you for 2 to 3 days? (I have no idea how long such a power cut would be expected to last -- I was surprised when you said 44hours!) Especially if only charged by the Sun? Can the AC coupled PW2 get charged by the Sun while the grid is down? Isn't you're solar inverter also offline?

When a Powerwall (and gateway) is installed with Solar, it will enable a regular inverter to stay on during an outage to recharge the battery.
That is one of the benefits of the Powerwall for retrofit installations.

[scrambler]

fresh off my first PSPS - 44 hours with no power.

i did manage to get an inverter connected to my bolt, but it wouldn't drive the only load i cared about inside the garage - the water heater. the heater controller gave a "reverse polarity" error but now that i'm thinking about it i wonder if it was unhappy that there was no earth ground, rather than the inverter not putting out the right waveform or voltage. i'll have to experiment now that the power is back and there's not as much stress involved.

I ran Two and an Half days off of our Chevy Volt Battery. I use a pure Sine wave 1500 / 3000 W inverter with a 100A breaker protection (you are not supposed to pull more than 1000W from the Volt through the 12 V battery). We were able to leave the Fridge, internet (as long as the service was up), the TV and some light on it the whole time, and recharging phones and laptop.


What I did learn was that my power strip would not work at first (it would only work directly connected to the inverter), then I realized I had not connected the Inverter Ground to the Car Ground. Once I did that, the power strip worked.

We were lucky to have a gas water heater that does not require any electricity.

[blueman2]

“Apologies to those waiting for Solar/Powerwall outside California, as we are prioritizing those affected by wildfires,” Musk tweeted today.

[JSchnee21]

How many kWh do you typically use per day? Can two or three PowerWall2 sized batteries (or similar) really cover you for 2 to 3 days? (I have no idea how long such a power cut would be expected to last -- I was surprised when you said 44hours!) Especially if only charged by the Sun? Can the AC coupled PW2 get charged by the Sun while the grid is down? Isn't you're solar inverter also offline?

IMHO, I think PS&G is just doing this for show to get the regulators and state to say "Uncle" and draft some sort of "Act of God" indemnity legislation for them. Seriously, their best solution is to turn off power when it's dry and windy? That's such BS.

Of course that's no comfort to those who were impacted.

[J.P.M.]

I just saw a note that Telsa is offering $1000 discount to those of us impacted by PGE PSPS. But I am sure they are already backed up 6+ months on installation.

I'd check and see if there was a price increase of $1K just before the discount appeared. It's just business.

[blueman2]

I just saw a note that Telsa is offering $1000 discount to those of us impacted by PGE PSPS. But I am sure they are already backed up 6+ months on installation.

[JSchnee21]

A few other suggestions:

1) Invest in several large USB battery packs and keep them charged for unplanned outages. Use these to charge phones, hotspots, USB lighting, etc.

Battery
https://www.amazon.com/Anker-PowerCore-20100mAh-Portable-Delivery/dp/B071WNWRNC/ref=sr_1_5?keywords=anker+battery+pd&qid=157234756 7&sr=8-5

https://www.amazon.com/Anker-PowerCore-Portable-Capacity-PowerPort/dp/B01K6TA748/ref=sr_1_14?keywords=anker+battery+pd&qid=1572347605&smid=A294P4X9EWVXLJ&sr=8-14

Lights -- these are amazing, really bright. Runs for >6 hours on 10,000 mAh

https://www.amazon.com/gp/product/B0198VDWMY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Flashlight

https://www.amazon.com/gp/product/B01KH2JP5G/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

2) Switch to a more reliable cellular operator -- AT&T or Verizon, or both which has UPS in place for emergency responders. Consider a dedicate cellular/Wifi hotspot for internet and phone access.

3) When Sandy hit, most people's home internet networks (Verizon FIOS and Comcast xFinity) were actually up and running. But folks couldn't use them as their house/Wifi had no power. Don't forget to run these off of your generator (or UPS) and check. This can be a real "lifesaver" if you have bored or scared kids with nothing to do (-: And iPad and a Cellular Hotspot or home internet will keep them out of your hair while you deal with real issues.

4) you probably won't have issues with water filtration. But lifestraws work wonders if you're concerned your local wasteplant was flooded or lost power

https://www.amazon.com/LifeStraw-Personal-Camping-Emergency-Preparedness/dp/B006QF3TW4/ref=sr_1_1_sspa?keywords=lifestraw&qid=1572347971&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyQURQQU9WTTcxVVlEJmVuY3J5cHRlZElkPUEwMDE3NDg4MVFTNzlTTVNKMEZVOSZlbmNyeXB0ZWRBZElkPUEwNTMyMDcwVFRDVVBPNlpSRUlEJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

[JSchnee21]

During hurricane Sandy, we discovered our hot water heater (AO Smith Power Vent w/Electronic Control Board and Electric Igniter) was equally fussy. It would run off of my neighbors older, smaller generator but not my larger, shiny new one (both portable). It turns out it needed to have floating ground (I think I'm remembering right -- I had to remove the bonding leg on mine) AND it needed to be non-GFI else when the electronic igniter would try to start the natural gas, it would trip the GFI. After "correcting" these issues it now works fine. Bonded vs. non-bonded is a common issue -- lots of detail on various forums. The OSHA's recent (at that time) mandate for GFI on generators was fairly new.

Rewiring the furnace and dishwasher to use a plugs was also a small headache at the time when you're in the midst of it. It would get cold at night in October here, and with two small infants we had a lot of dishes, laundry, etc.

But, if you have natural gas, I'd strongly recommend looking into an 1800rpm Nat Gas generator instead. It's cheaper (to purchase and install-- though not to operate), and will give you unlimited run time. But if you think a battery storage solution can give you the runtime you're need, by all means.

Or at least get an external, manual transfer panel for your portable generator and an Autotransformer to balance the legs. Purchasing, running, and storing enough extension cords is a huge headache, speaking from personal experience, not to mention the trip hazard, fire hazard, and trying to find a way to close/seal and secure up the door crack(s) they pass through from outside

[astroboy]

fresh off my first PSPS - 44 hours with no power.

it got real old setting up the generator each morning to run the fridge and freezer - didn't want to run it at night unattended. not being able to charge devices overnight was a hassle... and then trying to decipher whether or not PGE would get us up and running again before tuesday's new wind event was torture. i'm almost willing to pay whatever they are asking for a powerwall just to put this kind of crap behind me.

i did manage to get an inverter connected to my bolt, but it wouldn't drive the only load i cared about inside the garage - the water heater. the heater controller gave a "reverse polarity" error but now that i'm thinking about it i wonder if it was unhappy that there was no earth ground, rather than the inverter not putting out the right waveform or voltage. i'll have to experiment now that the power is back and there's not as much stress involved.

[Ampster]

........ Not sure why you find it hard to access battery terminals. I don't remember any special difficulty on my Tesla or other EV's I owned (Chevy Spark EV, Mercedes B250e). I have seen people setup permanent battery cables with Anderson connectors for quick connect/disconnect. The frunk is perfect space for a small inverter. I have natural gas generator so EV would not be a primary backup power source for me either. However, it's a good and easy option to have.

The 12V battery in the MX is under the Frunk and I watched a ranger do a battery swap and it was a lot of screws. I haven't had the Model 3 long enough but I just might hook up some Anderson connectors to have a backup. That would be a good way to boot the car if the 12V died. I do have one of those 12V Lithium Jump starters because three the EVs I have had I have had the 12 V battery go dead. (RAV4EV, SmartED. and Fiat 500e. Those were very accessable. Never had it happen in the Tesla's though. The 12V swap out was because they could see the 12V battery was going bad and they proactively replaced it. Gotta love the online diagnostics.