Learn from my mistakes... lookback at my botched installation (NorCal PG&E Territory)

[jboy210]

Yeah, but we did the dishes and laundry during the evening peak. Bottom line, nobody had to pause and think "what time is it" before doing a chore. When people talk about ROI of a system; it's literally priceless to be able to keep this mindset of just doing what you need to do when you need to do it instead of looking at the clock.

When it gets hot enough to run air conditioning... I'm going to set the damn thing to 74 and not give a thought about pre-cooling the house or doing some energy rush-hour BS.

Try it out a few times before you give up things like pre-cooling for the evening. When the summer sun is out we can keep the house cool or even cold, charge the Powerwalls to 100%, and not have to buy any power. But if we run the A/C in the evening or night, with no solar production and no power from the grid, we can deplete our 2 Powerwalls pretty quickly. The same thing happens if we run the dryer that uses 7 kW (over 1/2 a powerwall) per hour.

 

[holeydonut]

Try it out a few times before you give up things like pre-cooling for the evening. When the summer sun is out we can keep the house cool or even cold, charge the Powerwalls to 100%, and not have to buy any power. But if we run the A/C in the evening or night, with no solar production, we can deplete our 2 Powerwalls pretty quickly. The same thing happens if we run the dryer that uses 7 kW (over 1/2 a powerwall) per hour.

Nah... we tried that pre-cooling malarkey before on some rush-hour integration with the Nest thermostats. Everybody hated it since it got too cold, then too hot. We intervened on the rush hour every time it kicked on since the baby starts crying and nobody's having a good time.

PS. That's why I got the third Powerwall under the large-scale SGIP program. And now the SGIP folks are telling me I didn't size the system properly. Potentially going to cost me $8,700. Ugh.

 

[Webeevdrivers]

What does PTO mean.

 

[TEG]

What does PTO mean.

Guessing: Power-Turn-On (system fully 'live') ? [ Edit: OK, I had the right idea but wrong words. ]

Not to be confused with Paid-Time-Off

Also, FWIW, TEG are my initials... I have nothing to do with Tesla-Energy-Gateway
( Someone from Tesla asked me about that once ! )


BTW, I hear Elon doesn't like when people overuse acronyms...

 

[jboy210]

What does PTO mean.

Permission to Operate. It is when the power company grants you permission to push any excess power you generate to their grid.

 

[jboy210]

Nah... we tried that pre-cooling malarkey before on some rush-hour integration with the Nest thermostats. Everybody hated it since it got too cold, then too hot. We intervened on the rush hour every time it kicked on since the baby starts crying and nobody's having a good time.

PS. That's why I got the third Powerwall under the large-scale SGIP program. And now the SGIP folks are telling me I didn't size the system properly. Potentially going to cost me $8,700. Ugh.

Is the $8,700 for a 4th Powerwall?

 

[holeydonut]

It stands for permission to operate. Without batteries the excess solar needs to go back to pg&e’s grid. But with batteries the excess just gets stored and PG&E sees nothing. On most days PG&E is the backup and I’m kind of operating off-grid in a way.

The cash ROI on this is a no brainer. 40 kWh usually costs me $15 bucks. So since PG&E now drags their feet on granting PTO, I’d be out many hundreds of dollars if I just sat on an idle system.

 

[holeydonut]

Is the $8,700 for a 4th Powerwall?

no, the large scale sgip was $8,700 to go from two Powerwalls to three Powerwalls. The third powerwall was essentially subsidized.

But PG&E now changed how they assess whether you need a 3rd powerwall. They’re telling it’s unlikely Id run my dryer and electric oven at the same time so my “peak” demand is only 10kW.

and as you said... a dryer alone is 7kW.

 

[h2ofun]

no, the large scale sgip was $8,700 to go from two Powerwalls to three Powerwalls. The third powerwall was essentially subsidized.

But PG&E now changed how they assess whether you need a 3rd powerwall. They’re telling it’s unlikely Id run my dryer and electric oven at the same time so my “peak” demand is only 10kW.

and as you said... a dryer alone is 7kW.

So are you saying they are challenging the green button data now?

 

[holeydonut]

So are you saying they are challenging the green button data now?

I don't think they're challenging the Greenbutton data - they're just telling me that based on what they see in my application I don't qualify. Basically they're implying I should have done what you did by just cramming 60 minutes of absurd load levels to drive up my "peak" usage.

I feel this is absurd on their part because they're basically penalizing me for not gaming the system.

I can point to the loads in my home for the NEC calc; and real data collected by energy monitoring devices. Running my dryer and oven at the same time (not something that is out of the ordinary) plus some lights/TV's will pull 15kW (60 Amps @ 240 volts). This is easy to prove and see.

Throw in just one of my AC condensing units and I'm well above 15kW.

But for now, SGIP says I should have plugged an EV into my house to just force the demand up. It's my fault for not gaming the data.

 

[Webeevdrivers]

Permission to Operate. It is when the power company grants you permission to push any excess power you generate to their grid.

Thankyou.

 

[h2ofun]

I don't think they're challenging the Greenbutton data - they're just telling me that based on what they see in my application I don't qualify. Basically they're implying I should have done what you did by just cramming 60 minutes of absurd load levels to drive up my "peak" usage.

I feel this is absurd on their part because they're basically penalizing me for not gaming the system.

I can point to the loads in my home for the NEC calc; and real data collected by energy monitoring devices. Running my dryer and oven at the same time (not something that is out of the ordinary) plus some lights/TV's will pull 15kW (60 Amps @ 240 volts). This is easy to prove and see.

Throw in just one of my AC condensing units and I'm well above 15kW.

But for now, SGIP says I should have plugged an EV into my house to just force the demand up. It's my fault for not gaming the data.

I would not call if gaming the system. It is just following the rules

 

[holeydonut]

I would not call if gaming the system. It is just following the rules

PG&E's Director of ESS said to me that going around creating loads for 60 minutes that weren't normal behavior was 100% gaming the system. But he also admitted a homeowner would have to do that for the sizing reporting to come in the homeowner's favor.

Regardless what PG&E thinks; my point is 4x Powerwalls is 83A of continuous load at 240v. And 3x Powerwalls is 62.5A. It makes more sense to prove a home has the reasonable expectation to consume that level; and that proof shouldn't come from some BS "greenbutton".

The NEC has ways to indicate likely continuous demand. The IREC provided a completely reasonable/realistic calculation of "demand" that would be sized to the generating facility.

 

[Vines]

PG&E's Director of ESS said to me that going around creating loads for 60 minutes that weren't normal behavior was 100% gaming the system. But he also admitted a homeowner would have to do that for the sizing reporting to come in the homeowner's favor.

Regardless what PG&E thinks; my point is 4x Powerwalls is 83A of continuous load at 240v. And 4x Powerwalls is 62.5A. It stands to reason that it makes more sense to prove a home has the reasonable expectation to consume that level; and that proof shouldn't come from some BS "greenbutton".

The NEC has ways to indicate likely continuous demand. The IREC provided a completely reasonable/realistic calculation of "demand" that would be sized to the generating facility.

I think rather than looking at it as gaming the system, think of it as a stress test. Next holiday, you will have your family over, and they or you or both have an EV. You will be cooking dinner using both the oven and the range and using the washer and dryer at the same time. Since you are using so much hot water, the HW heater also needs to come on and since there are 25 or more bodies inside plus cooking the AC needs to come on as well.

This is not gaming the system, its just planning for your eventual use case. Run all those loads for an hour, while cooking a fancy dinner, and doing laundry.

 

[holeydonut]

I think rather than looking at it as gaming the system, think of it as a stress test. Next holiday, you will have your family over, and they or you or both have an EV. You will be cooking dinner using both the oven and the range and using the washer and dryer at the same time. Since you are using so much hot water, the HW heater also needs to come on and since there are 25 or more bodies inside plus cooking the AC needs to come on as well.

This is not gaming the system, its just planning for your eventual use case. Run all those loads for an hour, while cooking a fancy dinner, and doing laundry.

Do you think I can generate a data point worth 60 minutes in the next few weeks and re-apply my SGIP application?

SGIP made it sound like a one and done rejection.

 

[Vines]

EDIT:
I think you can resubmit with 60 minute green button data, just have to wait again in SGIP purgatory.

Edit because I am not the SGIP guru.

 

[jboy210]

no, the large scale sgip was $8,700 to go from two Powerwalls to three Powerwalls. The third powerwall was essentially subsidized.

But PG&E now changed how they assess whether you need a 3rd powerwall. They’re telling it’s unlikely Id run my dryer and electric oven at the same time so my “peak” demand is only 10kW.

and as you said... a dryer alone is 7kW.

Thanks. Do you know if you can add a 3rd powerwall just because you think you need it if you are not on a subsidy? I have been thinking about adding one. Not sure if I will do it right away. I assume a PW3 will be appearing in a couple of years using the battery chemistry they talked about on Battery Day.

 

[holeydonut]

Thanks. Do you know if you can add a 3rd powerwall just because you think you need it if you are not on a subsidy? I have been thinking about adding one. Not sure if I will do it right away. I assume a PW3 will be appearing in a couple of years using the battery chemistry they talked about on Battery Day.

Adding the 3rd battery was because of many factors:


1) I looked at my actual home usage (like as a human being; not some Greenbutton pushing dolt), and determined 3 Powerwalls was in my best interest. Problem was I couldn't afford 3x Powerwalls.


2) I needed the 3rd Powerwall to be able to start an air conditioner when the utility was offline. The LRA of my Lennox units was deemed too high to even have one AC on the backup side with only 2x Powerwalls.


So my first plans (without the large-scale SGIP) was 2x Powerwalls as partial home backup.


3) If you look at that spreadsheet/picture I posted to start this thread, you'll see in the 4th week of November that: "PG&E planning identifies they are not comfortable with partial home backup solution since it would require two 125A breakers in the 200A main panel." Basically, PG&E was stopping my PV+ESS project because they didn't like Sunrun's partial home backup design.

PG&E and Sunrun never really did grasp the concept of a partial home backup where CT's metered loads upstream of the Gateway. As a result, Sunrun's designers actually relied in input from @Vines (he has been super helpful since I joined TMC asking questions). Unfortunately, Sunrun's designers drew this up really weird on their line diagram, and had some wonky OCPD placement on the MPU. Plus, Sunrun confusingly labeled the air conditioners as "facility loads" which PG&E thought was like another house or ADU. Anyway PG&E hated this design and straight up rejected my second attempt to get a disconnect date without a new design being produced.

I leveraged adding the 3rd Powerwall to do the whole home backup. This got PG&E off my back after we resolved the 120 percent rule BS, and I was finally able to proceed on budget.


Bottom line, PG&E wanted me to abandon my PV+ESS as partial home backup. So, the only way to proceed with PV+ESS was to apply for the large scale SGIP and get that 3rd battery. And now they're telling me my home is "sized wrong" SCREW THESE #@%$%*@ERS

 

[holeydonut]

Another update...

PG&E set someone in one of their blue trucks to my house so they could confirm the system was indeed installed as described in the line diagram provided in the NEM2-MT interconnection agreement. This line diagram also matches what the county inspected and approved back in December on the latest permit.

I think (because I can't get straight answers from anyone) is that almost 90 days have passed since the County inspected, they want to make sure I haven't done something to upgrade the system between the inspection and granting PTO. Of course the only reason it's been 90 days since inspection without PTO is because PG&E is super slowwwwwwww.

Anyway; just a heads up to anyone... don't monkey with your system between inspection and PTO since there very well could be a final-final look-over from PG&E.

 

[h2ofun]

Another update...

PG&E set someone in one of their blue trucks to my house so they could confirm the system was indeed installed as described in the line diagram provided in the NEM2-MT interconnection agreement. This line diagram also matches what the county inspected and approved back in December on the latest permit.

I think (because I can't get straight answers from anyone) is that almost 90 days have passed since the County inspected, they want to make sure I haven't done something to upgrade the system between the inspection and granting PTO. Of course the only reason it's been 90 days since inspection without PTO is because PG&E is super slowwwwwwww.

Anyway; just a heads up to anyone... don't monkey with your system between inspection and PTO since there very well could be a final-final look-over from PG&E.

I have my installer coming today to take pictures of my system for the loan company. She told me we need a final from county. Then that info gets sent to PGE for approval. Then PTO. What if the world could/would someone modify in the system?