Connected Solutions Real-World Experiences (MA - National Grid / EverSource)

[jsurpless]

Hey everyone

I was hoping that folks in Massachusetts could share their real-world experiences with Connected Solutions so far this year.

Asking because my mom lives in SE MA and has EverSource - her experience so far this year has been a bit disappointing. She's had overwhelming 3-hr events (18/20) with EverSource calling events almost every weekday for the last 3 weeks even when it was cool weather and/or cloudy out. This has resulted in only a 6.6 average kW discharge for the season which is a good deal lower than the relatively conservative estimates I'd made. Perhaps my estimates were too optimistic but also perhaps it has something to do with my estimates being based on National Grid events, as opposed to EverSource. Of course, they were also based on last summer so there's that possibility too.

So... could anyone share how their events are so far this year? I live in Bellingham and have National Grid - anyone out this way? I ask predominantly because I was counting on CS as a major offset to the cost of the PWs and this is weakening that offset.

Many thanks in advance!

 

[RHinCT]

Mine got down to 18%, not the 20% that it should have stopped at. And I just got a notice that it is "preparing for a grid event", even though the general rule was that we get notice the day before, which did not happen for today. I've got lightning everywhere around here. It is loosing power under such situations that is exactly why I paid all that money for 2 Powerwalls. In fact I'm surprised there hasn't been one of those emergency (not sure that's the word) calls when it would charge the PWs from the grid just in case the grid comes down. I've had a couple of those since my system went seven months ago.

 

[kb1ibt]

Mine got down to 18%, not the 20% that it should have stopped at. And I just got a notice that it is "preparing for a grid event", even though the general rule was that we get notice the day before, which did not happen for today. I've got lightning everywhere around here. It is loosing power under such situations that is exactly why I paid all that money for 2 Powerwalls. In fact I'm surprised there hasn't been one of those emergency (not sure that's the word) calls when it would charge the PWs from the grid just in case the grid comes down. I've had a couple of those since my system went seven months ago.

Storm Watch is the emergency calls you were referring to, as to the preparing… check the date, at least for me, it is preparing for tomorrow not tonight. Also the 18% is somewhat normal, there are times where it is draining faster than it can update the battery percentage numbers and once it settles down it is a percent or two below. Additionally there are times where in Storm Watch (most often seen in the winter) where the stored level slowly drops even when nothing is being pulled, and it will need to top itself off.

 

[jhn_]

Looking back at last year, the only times it wasn’t max rate (5kw per PW) was when they had some glitches at the beginning of the season.

That was my experience too. Our first year in the program, 2 years back, there were a couple events where the discharge seemed to be calculated to have the PWs discharge steadily through the whole event. There were also a few events shorter than 3 hours. They seem to have settled in on discharging at max rate for three hours if you can with more recent events.

 

[jhn_]

Mine got down to 18%, not the 20% that it should have stopped at. And I just got a notice that it is "preparing for a grid event", even though the general rule was that we get notice the day before, which did not happen for today. I've got lightning everywhere around here. It is loosing power under such situations that is exactly why I paid all that money for 2 Powerwalls. In fact I'm surprised there hasn't been one of those emergency (not sure that's the word) calls when it would charge the PWs from the grid just in case the grid comes down. I've had a couple of those since my system went seven months ago.

Either opt out of the events when you think you want backup or opt out of the program if backup is paramount to you.

 

[jhn_]

New event for July 5th and they’ve tweaked the details UI to now include when the Powerwalls will start reserving all their charge prior to discharge.

 

[appleguru]

Yesterday was a 3 hour event. I seem to recall the discharge rate was adjusted so the PW would be able to discharge over the 3 hours. I have 2 PW and at 10 kw they barely make it to 2 hours.

That’s the way it always works (except for one weird event last year)

 

[RHinCT]

as to the preparing… check the date, at least for me, it is preparing for tomorrow not tonight.

Yes, I missed that the date was the next day. Thanks for straightening me out!

 

[jhn_]

Event for July 6th is only two hours. Guess they finally did the math an realized that draining 80% of a 13.5kwh battery at a rate of 5kw only gets you 10.8kwh, about two hours worth.

 

[appleguru]

Event for July 6th is only two hours. Guess they finally did the math an realized that draining 80% of a 13.5kwh battery at a rate of 5kw only gets you 10.8kwh, about two hours worth.

I think they’ve understand that math perfectly well and do a mix of 2 and 3 hour events to limit their overall cost and also maximize the benefit to the grid based on estimated demand curves (after all, tesla PWs are not the only batteries in the program, and others may be better suited to 3 hour events)

 

[RHinCT]

On Wednesday they stopped draining mine around 7:00 PM, which was when my system had nothing left to give (down to 18%).

 

[RHinCT]

Also the 18% is somewhat normal, there are times where it is draining faster than it can update the battery percentage numbers and once it settles down it is a percent or two below.

Two percent doesn't sound like much, but 18 vs 20 is ten percent below what is promised.

 

[kb1ibt]

Two percent doesn't sound like much, but 18 vs 20 is ten percent below what is promised.

Don’t get me started about the difference between what the gateway sees and exposes to the API vs what the Tesla App shows, there is a weird set of math going on there that leads to a discrepancy of more than that.
But you can see from this graph from yesterday’s event (pulling data from the API and then converted to match the App values) that it does stop at what it believes is 20%, but then due to battery leveling over about 10 minutes it drops to 18%. But if you were to look at the raw data on the gateway (not displayed) it would be closer to stopping at 23.9% and then leveling down to 21.6%

 

[jgleigh]

There's a bottom buffer on the Powerwalls that's hidden in the app and it's not a straight percentage. It varies over the full battery range. I would venture they did this so that people could run their Powerwalls down to 0% but the batteries would still have some charge left so they weren't bricked.

 

[cwied]

There's a bottom buffer on the Powerwalls that's hidden in the app and it's not a straight percentage. It varies over the full battery range. I would venture they did this so that people could run their Powerwalls down to 0% but the batteries would still have some charge left so they weren't bricked.

Historical note: the original app did not do this adjustment. The 5% adjustment was added to the app later when they decided the built-in buffer wasn't enough. The app shows 0 when the battery is actually at 5. It shows 100 when the battery is at 100 . The adjustment is just applied linearly in between. app% = (battery% - 5)/95.

 

[Lmkwin]

So today's event.... Says event 5pm to 7pm. Drain starts at 5. Even get a count down clock as 7pm approaches. Event ends in 2 minutes. Event ends in 1158 milliseconds. Then event ends on the screen and it shows tomorrows scheduled event.

At 7:02 my batteries are still draining.


Continues to drain for 6 more minutes and then it goes to this


Now the Tesla App is showing NOTHING going on. Data still shows if you click on a source but all blanks on the screen. Went to check for an app update. There was one so installed it "minor bug fixes..." Still all blanks on the screen.

Update: Around 7:45 app went back to "normal" view.

 

[Lmkwin]

So let's say that MY battery is down after an event. An event is scheduled the next day. That day is cloudy or raining. Or let's say I notice that my batteries aren't going to be fully charged by the start of the scheduled event. Would it be better to Opt Out of the event as full discharge isn't going to happen on my side? Or go ahead with a less than full engagement? Does the NUMBER of events participated in factor into the final payment?

 

[kb1ibt]

So let's say that MY battery is down after an event. An event is scheduled the next day. That day is cloudy or raining. Or let's say I notice that my batteries aren't going to be fully charged by the start of the scheduled event. Would it be better to Opt Out of the event as full discharge isn't going to happen on my side? Or go ahead with a less than full engagement? Does the NUMBER of events participated in factor into the final payment?

Based on my experience from 2 years ago, I didn’t have PTO until the end of July, so I missed about 1/2 the events, and I got paid about 1/2 of what I did last year. So it is based on average of events for the whole season, not just the ones you participate in. Speculation, that opt-out button might be for the VPP in locations like Texas.

 

[jhn_]

Yeah we are still waiting for someone in Connected Solutions to click the opt out button to see if it works for us. Who is it gonna be?

 

[Lmkwin]

Based on my experience from 2 years ago, I didn’t have PTO until the end of July, so I missed about 1/2 the events, and I got paid about 1/2 of what I did last year. So it is based on average of events for the whole season, not just the ones you participate in. Speculation, that opt-out button might be for the VPP in locations like Texas.

I opted out of the 1st one. I'm in MA

 

[Metralla]

Two percent doesn't sound like much, but 18 vs 20 is ten percent below what is promised.

2% is the relevant number. The percentage of the percentage is meaningless.