Mass Save Connected Solutions Incentive

[brianbsl]

Did finally get my rebate today for the Summer (Tesla sent an email on Wednesday saying they have been mailed). I got a little screwed by how I got enrolled prior to my installation, but that was something I had asked for to de-risk the program (as in, I was only willing to proceed with the installation if I got into this program). The math checks out based on that date.

Note this is the first official email I ever got from Tesla on the program (that they payment was mailed) - I did not actually get an email upon enrollment - although that was in the very early days of the program so perhaps they have fixed that by now.

 

[MCamber]

Yes, you can both export a CSV and inside the app see a graph and sum for each source/destination. So if I go to yesterday, and choose to graph only Powerwall data, it shows me 0.6kWh. Its one of the more well-done solar app implementations (better than Enphase or SolarEdge's app's) but its app-only, no website access, and I don't think they ever show you any per-panel data even if you have Tesla solar with SolarEdge optimizers. You do get solar data even if you add Powerwall to an existing solar install.

I wonder if you were to use a Sense (or something similar) would you be able to tease out each Powerwall? Or would it be muddled in the solar loads? That said, I have friends who have Sense boxes, and based on their experiences not sure that this would be a way to go. One has gas heat but the Sense thinks he has 4 electric heating zones.

 

[MCamber]

This answers your last question as well, but it's because Tesla is taking a 20% cut here. When you fill out the program application with Tesla you have to choose to have them send the incentive to Tesla. So your utility will send the $225/$50 to Tesla, but Telsa only then sends you $180/$40 (in theory, although they have not yet but are responsive when I ask for the status). They say this is to cover the costs of running the program. Its annoying, but in their defense:

1. At this small scale, I really do thing they are at best breaking even on the costs of running this. I think there are 1-2 people at Tesla who work on this close to full time, but only in the low hundreds of households enrolled. So optimistically they would decrease this cut as the program scales, but that also seems unlikely.
2. Powerwall is still much better break-even than any other battery solution on the market (most kWh/$), much more than 20% better.
3. If you are participating in SMART also, the way the DC-attached battery solutions work (SolarEdge, Sunrun which is still SolarEdge, and Pika), you end up not earning SMART generation credits for those kWh (unless they have fixed this) because the gen credits are done using an AC meter provided by the utility which is after the entire DC plant.
4. I believe Sunrun is doing it where the end user doesn't get any of the credits and it's all "baked in" on the Sunrun lease/PPA.

These details are really interesting! In looking at the Mass Save website, it's not apparent that there's a 20% fee that the battery companies shave off from your participation payment (even when I clicked through to the vendor websites it doesn't mention the fees. Of course, they have some hedging language like "you can earn up to $X". I'm not intending to throw shade at the program, I think it's a really interesting way to encourage households to install batteries.

But given the SunRun terms, where you just get a $150 gift card once a year, given how expensive these systems are, I wonder why people would participate?

 

[brianbsl]

I wonder if you were to use a Sense (or something similar) would you be able to tease out each Powerwall? Or would it be muddled in the solar loads? That said, I have friends who have Sense boxes, and based on their experiences not sure that this would be a way to go. One has gas heat but the Sense thinks he has 4 electric heating zones.

I do have a Sense but I don't think it would be able to figure this out. Its also on my "heavy load" panel which is not backed up by the PowerWall's. I basically never use it anymore. I use my Enphase monitoring for solar production and whole-home consumption (I actually have a google sheet that calls their API), and I only check the Tesla app for discharge events. At the end of the month I put my meter readings into the sheet, and that adjust for the loss to the battery, but its not that meaningful. The initial charging of the battery was basically "metered" at the install time so my consumption just went up by ~26kWh that month.

 

[MCamber]

I do have a Sense but I don't think it would be able to figure this out. Its also on my "heavy load" panel which is not backed up by the PowerWall's. I basically never use it anymore. I use my Enphase monitoring for solar production and whole-home consumption (I actually have a google sheet that calls their API), and I only check the Tesla app for discharge events. At the end of the month I put my meter readings into the sheet, and that adjust for the loss to the battery, but its not that meaningful. The initial charging of the battery was basically "metered" at the install time so my consumption just went up by ~26kWh that month.

Huh, I thought (take this with a grain of salt as I'm not a Sense owner and have never played with one myself) that the discharge of the Powerwall would be measured because the discharge would travel through the household breaker... but as I write that I realize it might look no different than delivered electricity.

Still, a moot point as your Sense is on a different panel!

That sounds like a lot of spreadsheet work you're doing. The solar, whole-home consumption, and the Tesla discharge rates... but when you say it's not very meaningful, I wonder what's missing? Forgive my ignorance, but this seems like a ton of information.

 

[brianbsl]

That sounds like a lot of spreadsheet work you're doing. The solar, whole-home consumption, and the Tesla discharge rates... but when you say it's not very meaningful, I wonder what's missing? Forgive my ignorance, but this seems like a ton of information.

Basically what I am saying is that the PowerWall discharge really doesn't matter in the grand scheme of things, other than calculating what Tesla owes you. So I just ignore that in my overall PV calculations.
The Sense would measure the PowerWall discharge, but it can't tell the difference between the PowerWall supplied power and the grid supplied power.

As far as the spreadsheet, it all updates automatically (it calls Google AppScript that calls the Enphase API), so its not really any work on my part.

 

[MCamber]

Basically what I am saying is that the PowerWall discharge really doesn't matter in the grand scheme of things, other than calculating what Tesla owes you. So I just ignore that in my overall PV calculations.
The Sense would measure the PowerWall discharge, but it can't tell the difference between the PowerWall supplied power and the grid supplied power.

As far as the spreadsheet, it all updates automatically (it calls Google AppScript that calls the Enphase API), so its not really any work on my part.

Ah - I see! How many discharges do you get paid for? I assume not all of them, because you're using some of the PowerWall stored power yourself?

 

[brianbsl]

Ah - I see! How many discharges do you get paid for? I assume not all of them, because you're using some of the PowerWall stored power yourself?

You get paid for the full discharge wattage of all called discharges ("grid service" events), even if you self-consume some of the power.
You don't get paid for discharges that you do yourself if you have it set for self-powered mode when you discharge daily for time-shifting PV production.

 

[Tdreamer]

Just got an e-mail from Eversource today confirming they're now accepting applications for PowerWall.

https://www.eversource.com/content/...nergy/battery-demand-response-application.pdf. The e-mail stated to send a filled out copy of the application to [email protected].

 

[jsurpless]

Wondering you experienced any events this past winter?

 

[TOCBoston]

I have 2 PWs and solar and just signed up for the PW program with national grid.

Although net metering might make the PWs seem less important for rate offsets and more geared towards backup power, there is value in circumstances where you have excess generation annually. If I understand correctly, any extra net metering kWh at end of year cam be allocated to another property or donated. You cannot get paid for them. However, if you have PW on Self Powered you’re pushing less excess into grid and will therefore be less likely to have unused end of year power.

in our case, we sized the system for primary usage of home although it is secondary for us. We will certainly generate massive net metering credits if we use PW in backup mode exclusively without access to them as primary property is n differently NG zone.

I might be way off in my thinking here and the amount might not end up being consequential. Additionally, I’m not considering any potential wear on the PW batteries due to daily charge / discharge cycle seem in self powered mode. This is more prevalent this time of year with short days.

 

[masam]

Wondering you experienced any events this past winter?

I have two Powerwalls and apparently experienced events last Winter (December '19). I say "apparently" because I had no idea/notification that the events occurred and the only indication was the check I got from Tesla early in 2020. Just got the email from Tesla that the Summer payment is on the way . So far, I'm happy with this program and more than happy with the uninterrupted power during 15 outages over the year.
Also, just to add to the discussion, I took advantage of the Mass Save 0% loan. It was a bit of a hassle, but it was last Fall, when the program had barely started and I had to go back and forth with Tesla and National Grid to get all the right forms filled out. But, again, can't beat 0% interest.

 

[masam]

Did finally get my rebate today for the Summer (Tesla sent an email on Wednesday saying they have been mailed). I got a little screwed by how I got enrolled prior to my installation, but that was something I had asked for to de-risk the program (as in, I was only willing to proceed with the installation if I got into this program). The math checks out based on that date.

Note this is the first official email I ever got from Tesla on the program (that they payment was mailed) - I did not actually get an email upon enrollment - although that was in the very early days of the program so perhaps they have fixed that by now.

I had a similar experience - There was no official email or document that said I was enrolled. I did email my Tesla Energy contact a couple of times and he confirmed that I was indeed enrolled. The real confirmation was the check from Tesla early this year.

 

[brianbsl]

I have 2 PWs and solar and just signed up for the PW program with national grid.

Although net metering might make the PWs seem less important for rate offsets and more geared towards backup power, there is value in circumstances where you have excess generation annually. If I understand correctly, any extra net metering kWh at end of year cam be allocated to another property or donated. You cannot get paid for them. However, if you have PW on Self Powered you’re pushing less excess into grid and will therefore be less likely to have unused end of year power.

in our case, we sized the system for primary usage of home although it is secondary for us. We will certainly generate massive net metering credits if we use PW in backup mode exclusively without access to them as primary property is n differently NG zone.

I might be way off in my thinking here and the amount might not end up being consequential. Additionally, I’m not considering any potential wear on the PW batteries due to daily charge / discharge cycle seem in self powered mode. This is more prevalent this time of year with short days.

I don't understand what the PW's get you in this situation. They only holding 27kWh of power, which basically only counts in your favor once, plus the recharge and efficiency losses. Your net meter is measured on a monthly basis, the daily powerwall cycling does not help you there other than that one-time 27kWh. So yes you push less into the grid at peak hours (you flatten it out) but the total across a full month is the same, other than the efficiency loss of the powerwall. It does help the grid though, so I'm sure they appreciate it, the only gamble is that if the ConnectedSolutions program calls for an event and you do not have enough time to recharge that day (partial solar day or whatever) you may not earn your full discharge credit - so I turn the cycling off during the program windows.
Yes you can reallocate your OBC's, I think you can change the target a couple times a year, I'm not sure if you can just do a one-off transfer or what though. Only within the same load zone.
They are designed for daily cycling so I would not really worry about the wear out of the batteries. If it was like recovered car cells that would be one thing but on new cells it should be fine.

I still think its worth doing for a subsidized backup system, and a backup system that does not have all the mechanical issues of a generator (oil, exhaust, fuel, etc) certainly makes a ton of sense for a secondary home where you are not there all the time.

 

[TOCBoston]

I don't understand what the PW's get you in this situation. They only holding 27kWh of power, which basically only counts in your favor once, plus the recharge and efficiency losses. Your net meter is measured on a monthly basis, the daily powerwall cycling does not help you there other than that one-time 27kWh. So yes you push less into the grid at peak hours (you flatten it out) but the total across a full month is the same, other than the efficiency loss of the powerwall. It does help the grid though, so I'm sure they appreciate it, the only gamble is that if the ConnectedSolutions program calls for an event and you do not have enough time to recharge that day (partial solar day or whatever) you may not earn your full discharge credit - so I turn the cycling off during the program windows.
Yes you can reallocate your OBC's, I think you can change the target a couple times a year, I'm not sure if you can just do a one-off transfer or what though. Only within the same load zone.
They are designed for daily cycling so I would not really worry about the wear out of the batteries. If it was like recovered car cells that would be one thing but on new cells it should be fine.

I still think its worth doing for a subsidized backup system, and a backup system that does not have all the mechanical issues of a generator (oil, exhaust, fuel, etc) certainly makes a ton of sense for a secondary home where you are not there all the time.

Hi -

This install was intended for a backup solution, primarily. We were at a point where a generator was being considered for 10-12K. PW's with subsidies definitely made sense for us personally.

Your point about the credits is totally valid, except we don't have anywhere within same load zone to actually assign them to other than friends, I guess. They're good cooks so it's a worthy exchange.

What I was saying earlier is that if I have no good destination to point the credits to, why create them? NGrid would just eat them up at some point I believe. Minimizing that creation via the PW is a way to avoid that. Keep in mind I was pointing this in response to an earlier post that suggested there was no real way to see fiscal value in a NM + PW solution. This is certainly not the reason we bought the PW's because I don't believe it's significant enough to matter in most cases. Even with this being a secondary home for us and therefore generating significant excess I'm not sure it would be a determining factor in buying PW. But its probably $500-$700 a year net benefit in our specific case. Over 10 years it puts a dent in the cost of system.

 

[brianbsl]

Received my summer 2020 incentive payment today. Was for $1565 for two powerwall's, I had calculated $1563 based on the data I had exported from the app, so based on some rounding errors (probably due to the 5 min data from the app), basically exactly the same. Pleased with the data matching and the incentive value.

 

[masam]

Received my summer 2020 incentive payment today. Was for $1565 for two powerwall's, I had calculated $1563 based on the data I had exported from the app, so based on some rounding errors (probably due to the 5 min data from the app), basically exactly the same. Pleased with the data matching and the incentive value.

Eerily close to what I received. Combined with the winter incentive, and an optimistic outlook, two powerwalls generate around $2k per year. Over 5 years, that adds up. Again, in my situation, this makes it a no brainer to have these as a heavily subsidized, whole-house backup solution with 0 maintenance (except maybe dusting theses things occasionally ).

 

[Santiago1109]

Correct PowerWall is an AC connected system, even if you do Tesla Solar (usually with a SolarEdge string inverter with optimizers), so that point does not apply. On a SMART (not SREC) PV install, the Solar inverter AC power will go through the AC generation meter before connecting to the PowerWall gateway.

Question for you, currently in the proceeds of getting 2 powerwalls. I moved into my current home that already has Tesla solar panels but under SREC and Tesla is taking those credits since last home owners paid for the panels outright. I know I will get connected solutions $1400-2000 seems to be the figure. But will I also be able to enroll in SMART as well just the batteries as the panels are under SREC ?

 

[Santiago1109]

Question for you, currently in the proceeds of getting 2 powerwalls. I moved into my current home that already has Tesla solar panels but under SREC and Tesla is taking those credits since last home owners paid for the panels outright. I know I will get connected solutions $1400-2000 seems to be the figure. But will I also be able to enroll in SMART as well just the batteries as the panels are under SREC ?

 

[Santiago1109]

Question for you, currently in the proceeds of getting 2 powerwalls. I moved into my current home that already has Tesla solar panels but under SREC and Tesla is taking those credits since last home owners paid for the panels outright. I know I will get connected solutions $1400-2000 seems to be the figure. But will I also be able to enroll in SMART as well just the batteries as the panels are under SREC ?