My 11.2kW Tesla Solar Project - Portland, OR

[LadyLion]

@LadyLion, the question of turning off your PWs while you wait for PTO so as not to drain them has come up before on the forum. Here's a response from @Vines who works for a solar installation company and installs PWs.

Powerwall discharging before system turns on

I
Thank you for that. I am confused as it is the opposite of what the inspection fellow told me (see above post) and I specifically asked. He said the switches shouldn't be used.
Others please give your advice on turning off PWs: use the switches on side of PW or the PW breakers in the Gateway2??
@jboy210 @BrettS @Vines

 

[jboy210]

I
Thank you for that. I am confused as it is the opposite of what the inspection fellow told me (see above post) and I specifically asked. He said the switches shouldn't be used.
Others please give your advice on turning off PWs: use the switches on side of PW or the PW breakers in the Gateway2??
@jboy210 @BrettS @Vines

I don't have GW2 so cannot comment on that. However, I do have a generation panel that connects inverters and Powerwall to Gateway. Our instruction was not to use the PowerWall switches unless you need to reboot the PowerWall for some reason.

 

[BrettS]

I
Thank you for that. I am confused as it is the opposite of what the inspection fellow told me (see above post) and I specifically asked. He said the switches shouldn't be used.
Others please give your advice on turning off PWs: use the switches on side of PW or the PW breakers in the Gateway2??
@jboy210 @BrettS @Vines

Once your system is up and running, under normal circumstances I don’t believe that there is any need to turn off the powerwall with the breakers or the switch on the powerwall. However, if you want to turn off the powerwalls to conserve their battery before the system is turned on then I believe that turning them off with the switch on the powerwalls would be the better option. Turning off the breaker just stops power from going to or coming from the powerwalls.

That said, if your powerwalls have enough of a battery charge that you don’t think they are in danger of running out of power and/or you are periodically activating the system to charge the powerwalls then I wouldn’t worry about turning them off at all and just leave the powerwall switches and the breakers on all the time.

 

[LadyLion]

Once your system is up and running, under normal circumstances I don’t believe that there is any need to turn off the powerwall with the breakers or the switch on the powerwall. However, if you want to turn off the powerwalls to conserve their battery before the system is turned on then I believe that turning them off with the switch on the powerwalls would be the better option. Turning off the breaker just stops power from going to or coming from the powerwalls.

That said, if your powerwalls have enough of a battery charge that you don’t think they are in danger of running out of power and/or you are periodically activating the system to charge the powerwalls then I wouldn’t worry about turning them off at all and just leave the powerwall switches and the breakers on all the time.

I was also thinking of an extended power outage period( 3 days or more like last fall fire season). What if I wanted to draw nothing all night long. The refrigerator (can sleep off overnight with no entry), built in light timers, surge power strips throughout the house, etc altogether seem to draw .5 to .7 kW overnight. That would save me approx 5 kW to use for the extended outage. I have 3PWs but I lose approx 20% of my storage overnight.
If you do turn them off at the breakers do they still use some portion of their stored power for the fan or heater to take care of themselves as they are placed outdoors. I thought I had read somewhere not to use the switches but haven’t found it. Maybe it was as @jboy120 said above re. only use the switches for rebooting.
The other option would be to set the battery level reserve very high at night so it would not be available to draw down? So everything in the house would go dark/off. Is that better?

 

[BrettS]

I was also thinking of an extended power outage period. What if I wanted to draw nothing all night long. The refrigerator (can sleep off overnight with no entry), built in light timers, surge power strips throughout the house, etc altogether seem to draw .5 to .7 kW overnight. That would save me approx 5 kW to use for the extended outage. I have 3PWs but I lose approx 20% of my storage overnight.
If you do turn them off at the breakers do they still use some portion of their stored power for the fan or heater to take care of themselves as they are placed outdoors. I thought I had read somewhere not to use the switches but haven’t found it.

I don’t know that you really want to be turning the powerwalls off during an extended outage. If the powerwalls are manually turned off during an outage it won’t be easy to restart them and you’ll need to use a 12V battery to “jump start” the TEG. If you really wanted to conserve power like that what I would suggest doing is turning off the circuit breakers going to your fridge and your other branch circuits, but leave the powerwalls up and running.

If you turn off the powerwall breakers the powerwalls will still use their own internal power to condition their batteries, which is something that you would normally want them to do. I don’t believe that they will do that if you turn off the switch on the side of the powerwalls (which is why I suggested using that switch before PTO if they are about to run out of power and you want to maintain what little power they have left).

However, just to be clear, using the breakers or the switch on the side of the powerwalls to shut them off during an outage will result in them not restarting until the power comes back on or you jump start the TEG.

 

[wjgjr]

I don’t know that you really want to be turning the powerwalls off during an extended outage. If the powerwalls are manually turned off during an outage it won’t be easy to restart them and you’ll need to use a 12V battery to “jump start” the TEG. If you really wanted to conserve power like that what I would suggest doing is turning off the circuit breakers going to your fridge and your other branch circuits, but leave the powerwalls up and running.

If you turn off the powerwall breakers the powerwalls will still use their own internal power to condition their batteries, which is something that you would normally want them to do. I don’t believe that they will do that if you turn off the switch on the side of the powerwalls (which is why I suggested using that switch before PTO if they are about to run out of power and you want to maintain what little power they have left).

However, just to be clear, using the breakers or the switch on the side of the powerwalls to shut them off during an outage will result in them not restarting until the power comes back on or you jump start the TEG.

I would agree that it is much better to turn off breakers than the PWs, but I'm not sure even that is really a good idea for the fridge. Refrigerators/freezers are designed to run all the time, and turning them off for a few hours really won't save energy - it will just shift the load to later when it has to cool back down. And in the mean time, even if it is not long enough to be a health hazard, it can possibly cause food to spoil more quickly. I've also had issues with our water line freezing when we had an outage - apparently our fridge automatically circulates the water some to avoid this, but it can't do so if power is out.

Faced with an extended outage, I think I would be more likely to turn things off at the outlet - turn off power strips and/or unplug electronics that are not in use, rather than flip breakers.

 

[jboy210]

I was also thinking of an extended power outage period( 3 days or more like last fall fire season). What if I wanted to draw nothing all night long. The refrigerator (can sleep off overnight with no entry), built in light timers, surge power strips throughout the house, etc altogether seem to draw .5 to .7 kW overnight. That would save me approx 5 kW to use for the extended outage. I have 3PWs but I lose approx 20% of my storage overnight.
If you do turn them off at the breakers do they still use some portion of their stored power for the fan or heater to take care of themselves as they are placed outdoors. I thought I had read somewhere not to use the switches but haven’t found it. Maybe it was as @jboy120 said above re. only use the switches for rebooting.
The other option would be to set the battery level reserve very high at night so it would not be available to draw down? So everything in the house would go dark/off. Is that better?

Saving 20% is useful by shedding, but is it necessary? Based on my experience over these last fire periods I am pretty sure we could have survived several days of outages even if the power initially cut off at the most inopportune time such as at dusk. Going into these periods my 2 Powerwalls we fully charged from solar and from the grid because of StormWatch being on. I might have paid a bit more, but I knew that I would power in the morning. And hopefully, I would get enough power from solar to recharge for the next day.

 

[LadyLion]

I would agree that it is much better to turn off breakers than the PWs, but I'm not sure even that is really a good idea for the fridge. Refrigerators/freezers are designed to run all the time, and turning them off for a few hours really won't save energy - it will just shift the load to later when it has to cool back down. And in the mean time, even if it is not long enough to be a health hazard, it can possibly cause food to spoil more quickly. I've also had issues with our water line freezing when we had an outage - apparently our fridge automatically circulates the water some to avoid this, but it can't do so if power is out.

Faced with an extended outage, I think I would be more likely to turn things off at the outlet - turn off power strips and/or unplug electronics that are not in use, rather than flip breakers.

The reason I thought I would turn off the subzero overnight without issue is that last October we rented a Honda 2200 portable generator during the PSPS outage. It runs on gasoline. We turned it off overnight (noisy plus needs to be refilled with gas), and we didn’t need the electricity. Everything in the refrigerator was fine overnight and the temperature hardly changed.
We don’t have our own generator so when the PWs are depleted we will be without power if this happens again.

I am trying to make a strategy for an extended PSPS. The separate breakers in the house panel is a good idea. We analyzed how to get down to six only when we were considering a manual transfer box that only allows a limited number of breakers to be live when connected to a medium size portable generator. After a lot of investigation and considering the work of gasoline filling and bringing the generator out of storage to set it up, and noise etc, we decided on our Tesla solar system and 3 powerwalls.

 

[LadyLion]

Saving 20% is useful by shedding, but is it necessary? Based on my experience over these last fire periods I am pretty sure we could have survived several days of outages even if the power initially cut off at the most inopportune time such as at dusk. Going into these periods my 2 Powerwalls we fully charged from solar and from the grid because of StormWatch being on. I might have paid a bit more, but I knew that I would power in the morning. And hopefully, I would get enough power from solar to recharge for the next day.

That’s a great point. My concern is the smoke cover we are having today which has dropped our production significantly from a typical 7-8 kW at noontime to only 4.6 max today earlier to 2.8 now at 2pm.

 

[pdx_m3s]

I wrote a small novel...

 

[jboy210]

That’s a great point. My concern is the smoke cover we are having today which has dropped our production significantly from a typical 7-8 kW at noontime to only 5 earlier to 2.8 now at 2pm.

Agree, this smoke cover is an issue for us also. I guess we are "lucky" that StormWatch is activated. So we can charge the PowerWalls from the grid if we want.

The bad thing about Stormwatch is that it went on at 4 AM so we did not shut it off. And now the roof is generating 4 kW. So we have full powerwalls we paid PG&E retail to charge, but are also sending power to PG&E and getting only wholesale prices back. First world problems. And way better than last year when we had a total of 4 days without power.

 

[LadyLion]

Agree, this smoke cover is an issue for us also. I guess we are "lucky" that StormWatch is activated. So we can charge the PowerWalls from the grid if we want.

The bad thing about Stormwatch is that it went on at 4 AM so we did not shut it off. And now the roof is generating 4 kW. So we have full powerwalls we paid PG&E retail to charge, but are also sending power to PG&E and getting only wholesale prices back. First world problems. And way better than last year when we had a total of 4 days without power.

Strange, here on the other side of the Bay SW is not active, it is on Standby and toggled on.
Luckily I am at 94% and they are getting 1.4from solar panels, house is drawing 1.0, for total of 2.4 kW at this time, 3pm.

 

[LadyLion]

If you have Storm Watch toggled on, how do you know that Tesla has activated it? Do you have to keep checking the app? Where does the notification appear on a tablet ?, or is there an email option when it is active?

 

[gpez]

The reason I thought I would turn off the subzero overnight without issue is that last October we rented a Honda 2200 portable generator during the PSPS outage. It runs on gasoline. We turned it off overnight (noisy plus needs to be refilled with gas), and we didn’t need the electricity. Everything in the refrigerator was fine overnight and the temperature hardly changed.
We don’t have our own generator so when the PWs are depleted we will be without power if this happens again.

I am trying to make a strategy for an extended PSPS. The separate breakers in the house panel is a good idea. We analyzed how to get down to six only when we were considering a manual transfer box that only allows a limited number of breakers to be live when connected to a medium size portable generator. After a lot of investigation and considering the work of gasoline filling and bringing the generator out of storage to set it up, and noise etc, we decided on our Tesla solar system and 3 powerwalls.

Being in an earthquake zone and having only 1 Powerwall I've thought about this pretty extensively and have not yet (thank goodness) had to put this plan in to action.

Our average house consumption is about 24kWh with no conservation but also no EV or AC. Of course the ~12kWh Powerwall won't last overnight if we keep that up. So if we were to lose power for an extended period of time we'd work to conserve (limit lights and microwave, shut down non essential electronics) which would bring us down to 12kWh/day. Absolute minimum usage would be to run the refrigerator and kitchen freezer, a little bit of lights, and run the gas tankless hot water heater at about 6kWh/day.

In an extreme case where we're getting little or no solar the 12kWh Powerwall would last 2 days at a maximum, which obviously wouldn't be great. The other risk is that if the Powerwall is drained all the way down getting it back online can be challenging with the grid out even when there is full sun. That's why I invested in load shedding to my EV - simply a 1250w pure sine inverter I can hook up to my Volt and use it to power the fridge and freezer. If it ever gets to that I'd open the breaker to my backup panel (to stop any Powerwall draw) and run extension cords from the garage to the freezer and fridge. Crappy and manual but my back of the napkin math says I can get over 100kWh usable out of it with a full charge and full tank of gas.

 

[pdx_m3s]

Is payment due after inspection or PTO? My account has the "Inspection Passed" checkbox, but nothing about payment yet.

 

[jboy210]

If you have Storm Watch toggled on, how do you know that Tesla has activated it? Do you have to keep checking the app? Where does the notification appear on a tablet ?, or is there an email option when it is active?

It shows right on the front screen of the Energy part of the app. This is the screen with that the image of the powerwall and the percentage of charge. Right of the above that image is says "Storm Watch" in Orange. See below

 

[SMAlset]

Is payment due after inspection or PTO? My account has the "Inspection Passed" checkbox, but nothing about payment yet.

Yesterday we passed inspection and called about payment. Were told they were super busy with remitting invoices for installs and that there might be a slight delay in receiving ours depending where we were in the system. So I'm sure they are coming! We also have the checked Inspection Passed so were curious when we didn't see an invoice. Given the amount thought it would be there the moment we passed . Only anxious to receive as I know it means the PTO request to PG&E gets generated after payment is received and anxious to get that "turn on" message.

 

[jboy210]

Yesterday we passed inspection and called about payment. Were told they were super busy with remitting invoices for installs and that there might be a slight delay in receiving ours depending where we were in the system. So I'm sure they are coming! We also have the checked Inspection Passed so were curious when we didn't see an invoice. Given the amount thought it would be there the moment we passed . Only anxious to receive as I know it means the PTO request to PG&E gets generated after payment is received and anxious to get that "turn on" message.

After the Q3 push, the billing department may be taking the weekend off.

 

[LadyLion]

I would agree that it is much better to turn off breakers than the PWs, but I'm not sure even that is really a good idea for the fridge. Refrigerators/freezers are designed to run all the time, and turning them off for a few hours really won't save energy - it will just shift the load to later when it has to cool back down. And in the mean time, even if it is not long enough to be a health hazard, it can possibly cause food to spoil more quickly. I've also had issues with our water line freezing when we had an outage - apparently our fridge automatically circulates the water some to avoid this, but it can't do so if power is out.

Faced with an extended outage, I think I would be more likely to turn things off at the outlet - turn off power strips and/or unplug electronics that are not in use, rather than flip breakers.

In light of the above issues I could avoid turning off house or PV breakers or PW switches by instead setting the Powerwall “reserve to 100% “ overnight on the app.. Wouldn’t this be the same as having all power shutdown to the house at night when solar was not producing? Then there would be no reset/reboot issues. I realize this may not be ideal for the refrigerator but if I really need to conserve it could be a better option. @BrettS @jboy210 @gpez @SMAlset

 

[jjrandorin]

I am not any of the people you tagged, but those percentage backup settings are ignored in an outage situation. If you are thinking about shedding home loads during an outage, you would want to plan to do that at the devices individual breaker, if its a device that has its own circuit (microwave, pool pump etc) or, at the individual plug in outlet.

You would not be shedding any loads by cycling the powerwall off, or changing any settings in the app during an outage.