I forgot I ordered Powerwalls

[NathanielHrnblwr]

Until Tesla called today about my order after about 2 months since last contact.

The news was my 2 A/C units cannot be backed up. Sure start not an option. This isn't a huge deal as I don't use them often - maybe 4-6 weeks a year.

They can back up the HPWC for my Tesla. I wanted an option to charge the Tesla in the event of an extended outage besides a standard wall outlet. After further thought, I'm thinking backing up the HPWC isn't desirable. What if the power goes out during the night while the car is plugged into the HPWC and attempts to charge? Assuming the PW had power, it would likely shutdown due to load. Perhaps a separate 14-50 on the critical loads panel to use if necessary and leave the HPWC on the main panel?

In the back of my mind I'm still wondering of 2 is enough for my 9.9kWp. I forgot why I decided it was or if I just wanted to avoid the NGOM hassle. Now I have to remember again.

The financials don't pencil out with battery and I still have 2 more years left with 11a-6p peak TOU during summer making those sweet NEM credits. Too bad the power doesn't go out more to help convince me PW's are a good idea.

 

[aesculus]

MY heat pumps cannot be isolated from the backup panel so it's up to me to cycle them off. Looking at an automated way to do this when I am not at home.

I did not backup my HPWC for just the reason you stated. I can always get to a SC that never goes down about 15 miles away and is also not affected by the PSPS program so I did not feel the need to have the car charger backed up. Also it would drain my two PWs.

 

[jjrandorin]

OP, I just had my 2 powerwalls installed Jan 6th. I did NOT backup my HPWC for the exact reason you stated. I also am having a 14-50 put on the backup side for the reason you specified (to be able to provide a "little power" to my car if I wanted to, enough to get to a local super charger if I had to, in an outage situation).

I expect to never need that 14-50 but want it there on the backup side "as a backup".

I live in temecula actually, and work in Oceanside. Right now (as I type this) my powerwall is under day 2 of "stormwatch" mode due to high wind advisories in my area from yesterday to friday. I cant even describe how incredibly "comforting" it is to know that, even if the wind takes down a powerline, that I will still have power (and I didnt have to do anything other than having toggled the stormwatch mode on when it appeared in the app, 2-3 days after install.

I am on a regular tiered plan, so the more I use, the higher the price (one of the old school plans, that have a small tier 1, then tier 2 then tier 3, at 19 cents, 28 cents, and like 42 cents or something. So, for me, I need to reduce overall usage, not time of use. Because I am under NEM 1 they pay me 19 cents for my solar as far as NEM credits go, and most of the charges can be zeroed out as long as I am a net consumer insteed of net producer.

Switching to any time of use plan increases my costs so it doesnt pencil out that way for me. I still bought them though, and really happy I did.

My AC units are backed up as well, and as you likely know, we need AC more here in Temecula than you do in Oceanside.. summers are hot here, relative to you.

 

[jboy210]

MY heat pumps cannot be isolated from the backup panel so it's up to me to cycle them off. Looking at an automated way to do this when I am not at home.

I did not backup my HPWC for just the reason you stated. I can always get to a SC that never goes down about 15 miles away and is also not affected by the PSPS program so I did not feel the need to have the car charger backed up. Also it would drain my two PWs.

I feel the same way. We have 2 Teslas and if we need to charge them during an outage we have 5 Superchargers within 15 miles. However, the house can only be powered during an outage by the PowerWalls. So the house is the priority for the PowerWalls.

And unfortunately we are hit by PGE PSPS. We got 4 warnings and 2 actual shutdowns this fall for a total of 3 days without power. I assume until they bury the power lines we can look forward to this each late fall.

 

[Dan123]

I think 2 is enough if you don't have AC backed up. Frankly, even 1 might be enough, depending on your home's baseline usage.


As for HPWC - yes, it is possible that if the power goes off while the car is charging, the PWs will be drained fast. How likely is that to happen? And if it does happen, you will need to unplug your car, and the power will come back on when the sun is out.

 

[aesculus]

And unfortunately we are hit by PGE PSPS.

Just to be clear our house is too. It's the SC 15 miles away that aren't hit in my case.

 

[jboy210]

Just to be clear our house is too. It's the SC 15 miles away that aren't hit in my case.

Understand. Also, I don't know about your neighbors, but thanks to the PSPS, many of mine are interested in PowerWalls and the SolarGlass roof.

 

[Dave EV]

Perhaps a separate 14-50 on the critical loads panel to use if necessary and leave the HPWC on the main panel?

This is a good idea, and what I plan on doing when/should I get Powerwalls.

 

[NathanielHrnblwr]

I think 2 is enough if you don't have AC backed up. Frankly, even 1 might be enough, depending on your home's baseline usage.


As for HPWC - yes, it is possible that if the power goes off while the car is charging, the PWs will be drained fast. How likely is that to happen? And if it does happen, you will need to unplug your car, and the power will come back on when the sun is out.

Average weekday usage with car charging is 50kWh with about 10kWh self consumption from solar. If the car doesn't move for the day, it's about 30kWh, so figured 2 would provide enough power between sunset and sunrise if the outage was that long. Thinking ahead to when I'm forced to 4a-9p peak TOU, one should be sufficient to cover peak with the 2nd able to be sufficiently charged for backup in case of a short outage.

 

[NathanielHrnblwr]

OP, I just had my 2 powerwalls installed Jan 6th. I did NOT backup my HPWC for the exact reason you stated. I also am having a 14-50 put on the backup side for the reason you specified (to be able to provide a "little power" to my car if I wanted to, enough to get to a local super charger if I had to, in an outage situation).

I expect to never need that 14-50 but want it there on the backup side "as a backup".

I live in temecula actually, and work in Oceanside. Right now (as I type this) my powerwall is under day 2 of "stormwatch" mode due to high wind advisories in my area from yesterday to friday. I cant even describe how incredibly "comforting" it is to know that, even if the wind takes down a powerline, that I will still have power (and I didnt have to do anything other than having toggled the stormwatch mode on when it appeared in the app, 2-3 days after install.

I am on a regular tiered plan, so the more I use, the higher the price (one of the old school plans, that have a small tier 1, then tier 2 then tier 3, at 19 cents, 28 cents, and like 42 cents or something. So, for me, I need to reduce overall usage, not time of use. Because I am under NEM 1 they pay me 19 cents for my solar as far as NEM credits go, and most of the charges can be zeroed out as long as I am a net consumer insteed of net producer.

Switching to any time of use plan increases my costs so it doesnt pencil out that way for me. I still bought them though, and really happy I did.

My AC units are backed up as well, and as you likely know, we need AC more here in Temecula than you do in Oceanside.. summers are hot here, relative to you.

Stormwatch for winds? Interesting. Does it charge it up at night at low rates or is it random?

 

[jjrandorin]

Stormwatch for winds? Interesting. Does it charge it up at night at low rates or is it random?

When stormwatch triggers, it just starts charging. I am sure the thought behind that is, "we are ensuring your powerwalls are full or as full as we can make them due to a weather event. If you didnt want this to happen, you would turn off the stormwatch setting. If you have the storm watch setting on, then you likely dont care about the cost and would rather have the powerwalls full".

We have a high wind advisory going on right now, with warnings that there could be downed power lines etc for my area (reported in weather apps like the weather app, and dark sky). I am actually happy to see stormwatch triggered in such a scenario because I otherwise run in self powered mode with a 30% reserve.

 

[d21mike]

One of the YouTube channels I watch after putting in a very large system in Colorado (I believe) had the problem with power outage causing the power walls to be drained by the cars over night. He posted that to Elon asking for an option to say do not do scheduled charging during a power outage. Which should be easy to do in the API. Elon agreed with a post but nothing has happened yet. I have whole home backup so hope it happens. They had a problem getting sure start to work on my AC. Twice failed then they brought in a guy with more experience and got it working in < 15 minutes. If you do not have a HWPC then get GEN3 because it has Wi-Fi for better control. Maybe there will be more options with it. Just came out recently.

 

[gpez]

I don't have a Tesla (or an HPWC) but I did have the installer put in a 14-50 outlet in my garage as part of the PV + Powerwall install however since a) I only have one Powerwall and b) if there is a grid outage I don't want my EV charging off the Powerwall I opted to put it on the non backed up side. I do have plenty of 15a 120v outlets that are backed up so in a pinch I can just plug my EV in there.

 

[NathanielHrnblwr]

Thanks for the feedback. Tesla says they can't install the 14-50 so I'll have to handle that on my own.

 

[d21mike]

Thanks for the feedback. Tesla says they can't install the 14-50 so I'll have to handle that on my own.

When I got my first Tesla I had a 14-50 installed and it worked fine. After I got my second Tesla I had Tesla install 2x HPWC gen2 which replaced the 14-50 while installing solar/Powerwalls. I prefer this setup. I recommend you consider the HPWC gen3 which has more features including Wi-Fi. I put mine on 1 60amp circuit using load balancing. Works great. Like me you may have more Tesla’s in you future.

 

[jjrandorin]

When I got my first Tesla I had a 14-50 installed and it worked fine. After I got my second Tesla I had Tesla install 2x HPWC gen2 which replaced the 14-50 while installing solar/Powerwalls. I prefer this setup. I recommend you consider the HPWC gen3 which has more features including Wi-Fi. I put mine on 1 60amp circuit using load balancing. Works great. Like me you may have more Tesla’s in you future.

OP is talking about tesla not being able to install the 14-50 while doing his powerwalls, on the backup side. They wont do it unless its part of the scope of work laid out in the beginning (he has solar already and is adding powerwalls).

 

[NathanielHrnblwr]

The 14-50 outlets I ordered arrived. I went for the Cooper (now Eaton) higher quality outlets. Found them pretty cheap online for $13. Great! Oh, $5 fee for orders less than $20 or something, fine. I'll order 2 - can always give one away or use elsewhere. Website can't calculate shipping but option to preapprove them to add whatever it is to the order and bill it. Sure, why not. How much can UPS ground for 2 outlets cost that weigh less than a pound cost?

$20! lol

seriously. $45 for two outlets. So much for that deal!