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Software versions for Powerwall 2?

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Okay, I don't think we need to battle over TOU implementation details on this Tesla forum, but PW "reserve" == Sonnen "backup-buffer". Discharging during TOU when no solar is available (or enough to cover loads) is the correct and more economical behavior no?

Sorry if it seems like I'm battling, that is not my intent. The point mainly was that Tesla may need a different agreement with the power company than Sonnen has as they're trying to be more aggressive with their TOU implementation.

Presuming net metering, the most economical behavior from a TOU perspective is to ignore solar and cover the highest tariff loads irrespective of whether solar is available to cover it or not. This would result in a higher net metering credit as more solar would get exported.
 
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Okay, I don't think we need to battle over TOU implementation details on this Tesla forum, but PW "reserve" == Sonnen "backup-buffer". Discharging during TOU when no solar is available (or enough to cover loads) is the correct and more economical behavior no?
For people with net metering agreements, the most economical solution is to offset all of the house usage during Peak Rate TOU (regardless of solar production) and send all the solar produced to the grid. That maximizes the credits generated from solar and should not require any new export agreement with the power company. from the power companies point of view, it is the same as turning off everything in the house during the peak rate period.
 
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For people with net metering agreements, the most economical solution is to offset all of the house usage during Peak Rate TOU (regardless of solar production) and send all the solar produced to the grid.
You can do a little bit better if the energy storage system is sufficiently configurable: You can also time shift all your solar production to export to the grid during Peak Rate TOU.

Cheers, Wayne
 
You can do a little bit better if the energy storage system is sufficiently configurable: You can also time shift all your solar production to export to the grid during Peak Rate TOU.

Cheers, Wayne
For SDG&E, and I think most other California Utilities, the Net metering agreement only allows for excess solar production to be push onto the grid. I doubt they would interpret that the same as pushing to the grid from the batteries (even if the energy in the battery was from solar originally).

If time shifting solar is allowed by the utilities, then it would be the best setup by far.
 
It looks like the PG&E interconnect agreement calls the Powerwall a "Non-NEM Eligible Energy Storage System." I think this effectively means that the export at any time cannot exceed what the PV system is generating or it would be deemed not to be NEM-eligible.
 
My statement is based on reading the PG&E NEM 1.0 tariff, which has a section on having a Renewable Generator (solar panels) paired with an Energy Storage System, section 11 I think. It states that their billing software may use a model of your solar panels to determine an estimate of how much production your system makes each year, and they may check that your total export to the grid for the year does not exceed their estimate. I took that to mean that any behavior satisfying that restriction is OK, meaning that solar production time shifting using batteries is OK.

BTW, in speaking with a few people at PG&E on other matters, I asked if they could confirm that their billing software has implemented the above algorithm, and no one knew one way or the other.

Cheers, Wayne
 
It looks like the PG&E interconnect agreement calls the Powerwall a "Non-NEM Eligible Energy Storage System." I think this effectively means that the export at any time cannot exceed what the PV system is generating or it would be deemed not to be NEM-eligible.

Where do you see that? All of the CPUC-regulated utilities have language about "NEM-paired storage". "Large NEM-paired storage" (more than 10 kW) must be 150% or less of the solar generation maximum output. But a single Powerwall 2 is 5 kW.
 
Where do you see that? All of the CPUC-regulated utilities have language about "NEM-paired storage". "Large NEM-paired storage" (more than 10 kW) must be 150% or less of the solar generation maximum output. But a single Powerwall 2 is 5 kW.

It's specifically from the Interconnection agreement that Tesla submitted to PG&E for my installation. I don't know if it was a choice not to include it in NEM or a requirement, though.

Edit: it appears the form doesn't allow for adding storage that is included in NEM.
 

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Hmm.. I would certainly question Tesla on why it's not considered NEM-eligible.
After doing a couple more Internet searches, I don't think it's Tesla's issue. It's just how PG&E allows the interconnection. You can see the sample for 79-1193 here: https://www.pge.com/tariffs/assets/pdf/adviceletter/ELEC_5140-E.pdf

It's possible that other utilities have different policies, but PG&E doesn't seem to allow the batteries to be included in NEM when paired with solar.
 
the most economical solution is to offset all of the house usage during Peak Rate TOU (regardless of solar production)
You can do a little bit better if the energy storage system is sufficiently configurable: You can also time shift all your solar production to export to the grid during Peak Rate TOU.

In Australia the first quote is the best for us - the second quote doesn't apply here - the Feed-In-Tarrif is the same all day long.
 
For those of us on PG&E NEM 1.0, I believe the controlling document is Electric Schedule NEM.

If you look at the advice letter I linked above, it has both NEM 1.0 and NEM 2.0 versions of the interconnection agreement. I suspect it matters when you signed the interconnection agreement. Those who signed before September 2017 might be able to get paid according to the original document. I suspect those of us who signed more recently got the new version will be more limited in our options.
 
It's not spelled out, but the storage system is listed under "non-NEM eligible storage system." My interpretation is that because I signed one of these agreements, my storage system is not NEM eligible, while the PV system is. I'm guessing those who signed an earlier interconnect agreement probably would be allowed to export according to the orginal NEM document.
 
In this case I think there's a change over time. The original document is from 2016. In September 2017, they added the interconnect form with the "non-eligible". In December 2017, they added a paragraph about smart inverters.
 

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The setup wizard. It’s accessible from the web interface.

Wow, lots of interchange on this since I asked the question just four days ago! And thanks to that interchange between you and gregsapphire, I've gotten to the wizard!

It turns out that my installer set up cellular for the Backup Gateway Internet connection. I saw the TEG-xxx in my WiFi list after seeing someone else mention it in another forum/thread. I was able to connect to that network and get into the Powerwall UI using the IP address of 192.168.91.1, which is apparently the default IP address for the cellular connection based on what I've seen others mention. I was able to log in using the serial number of the Backup Gateway, although that was a little confusing because my installer also appended an "S" to the front of the serial number. Also, one of the digits/characters is actually an upper case "I" (eye), not a "1" (one) or a lower-case "l" (ell). So my password is ST17I0008xxx, where xxx is the last 3 digits of my Backup Gateway serial number.

After logging in to the UI I was able to run the wizard. I noticed the warning that running the wizard will shut down the Powerwall and that apparently the only way to start it up again was through the UI, so I was really hoping that this was going to work! I went out to the garage and saw that the green lights on the two Powerwalls were both flashing, so that's apparently what they do when they're shut down. Screen 1/11 allowed me to change the Internet connection to WiFi, so I selected that. Just for the heck of it I also went through all of the screens and changed the name of my installation to a more personalized one. Then I reconnected to my local WiFi network, looked in my router's DHCP Client Table and found the IP address that the Powerwall was using. For good measure, I also went into the router DHCP Reservation Table and reserved that IP address and gave it a more friendly name (Tesla-PW2 instead of 1118431-00-G--T17I0008xxx).

Then I browsed to the IP address of the Powerwall on my local network and was again at the Powerwall UI! Success! I started the Powerwall, went to the garage and heard some clicking and then the Powerwalls started humming and went into their glow sequence, so they came up again with no problem.

The reason that I wanted to access the wizard and get it on my local network was to be able to set up data aggragation using PVOutput.org as documented on the MikesGear.com site: Monitoring Tesla’s Powerwall2 on PVOutput.org. So my next project is to get that up and running. It needs an always-on PC however, and I saw somewhere that someone set his up using a Raspberry Pi, so that's another task to get it up and running on that.

While I was mucking around in my router I noticed that the firmware was outdated so I took the opportunity to upgrade it. After the router rebooted I discovered that the Backup Gateway had reverted back to the cellular connection, so I had to go back in and change it back to WiFi. We have a long trip coming up and that got me to wondering what would happen with the Powerwall Internet connection if my network went down while I was gone. Apparently, Tesla has that covered.

Something interesting that I noticed was that when I looked in my router's outgoing traffic log, the Powerwall IP connected to 69.89.207.99, which I assumed was Tesla. Imagine my surprise when i got a standard Apache2 Ubuntu Default Page! Not sure what my Powerwall was doing at that page and how Tesla is getting the data, but it makes me wonder how secure their data collection setup is if they didn't even bother to change the default page.

Many thanks for your help and the interchange between you and gregsapphire!
 
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