New Powerwall Advanced Options [Toggles for charging from and discharging to grid from powerwalls]

[swedge]

Tesla also requires adding more solar to my existing 4 kw system

A few thoughts:

Third party installers can retrofit PW to existing solar. Semper Solaris added PW to my 3.8 kW solar, and did all the SGIP paperwork. Tesla had maxed out on their SGIP allocation, and for me that was disqualifying.

When working out ROI, income tax credit can help a bit. Also check for rebates, though I think SGIP may be all wait-list now.

The main benefit, power outage backup, is hard to quantify economically, but zero is the wrong number. Furthermore, complexities in utility pricing and PW features make NEM benefits difficult to estimate.

It helps a lot if you have a year of your consumption and solar history data and some time to kill. I did an hour by hour spread sheet (8,760 lines) to help me chose the best rate plan. But that turned out moot because SGIP allowed only EV2-A, which was the best option for me anyway.

During the first PSPS shutdown with our PW, several neighbors wondered how I kept our driveway lights on, and some came over to borrow internet access. Now several have had PW's installed.

My advice would be to go for it if you can afford it, get the best price/rebate/discount/tax credit you can, and figure out how to best use it as you go along. After installation, the hard part is waiting for an actual power outage, at which point you'll know you did the right thing. Once you've spent the $, you'll make adjustments to minimize your true-up, but you won't worry about ROI again.

SW

 

[sunwarriors]

waiting for an actual power outage

I'm waiting for this still...

The way I look at batteries is less ROI, but more it's $$ I can't waste some other way. With how expensive Tesla cars are (Model S/X or any Lux brand), a few batteries doesn't seem that costly at the end of the day compared to spending $20k on some other toy (assuming you have the $$).

I think there is a certain piece of mind too that grid goes down: What, Me Worry?

 

[h2ofun]

I'm waiting for this still...

The way I look at batteries is less ROI, but more it's $$ I can't waste some other way. With how expensive Tesla cars are (Model S/X or any Lux brand), a few batteries doesn't seem that costly at the end of the day compared to spending $20k on some other toy (assuming you have the $$).

I think there is a certain piece of mind too that grid goes down: What, Me Worry?

My thoughts are first, just get AS MUCH solar on your roof, period. Does not matter direction! This is the return.

My next thought is I would not buy batteries. I am looking at the first EV that will support v2h. Much better return. Ford 150? Leaf? I just told a person today, IMO, batteries are a waste of money. They have done nothing for me to save money. I save because I have tons of solar. I have not had a power outage for like what 3 years.

 

[bmah]

My thoughts are first, just get AS MUCH solar on your roof, period. Does not matter direction! This is the return.

My next thought is I would not buy batteries. I am looking at the first EV that will support v2h. Much better return. Ford 150? Leaf? I just told a person today, IMO, batteries are a waste of money. They have done nothing for me to save money. I save because I have tons of solar. I have not had a power outage for like what 3 years.

This is where peoples' different situations affect their power system designs. Congrats on zero power outages (I mean that really).

Here in the wilds (?!?) of Lafayette, we had multi-day power outages in 2019 and 2020, and hours-long outages in 2021 and 2022. Thanks to Powerwalls and solar we were lights-on the entire time. Like @swedge pointed out in a post earlier, the benefit of keeping the electricity on in your house is hard to quantify but definitely non-zero. V2H is a wonderful idea but it isn't widely available yet, and fixed batteries have done great for me thus far these past few years.

(I do wish I had more solar too, but back in 2010 even getting the 5.8kW system we have seemed like a radical idea.)

Bruce.

 

[h2ofun]

This is where peoples' different situations affect their power system designs. Congrats on zero power outages (I mean that really).

Here in the wilds (?!?) of Lafayette, we had multi-day power outages in 2019 and 2020, and hours-long outages in 2021 and 2022. Thanks to Powerwalls and solar we were lights-on the entire time. Like @swedge pointed out in a post earlier, the benefit of keeping the electricity on in your house is hard to quantify but definitely non-zero. V2H is a wonderful idea but it isn't widely available yet, and fixed batteries have done great for me thus far these past few years.

(I do wish I had more solar too, but back in 2010 even getting the 5.8kW system we have seemed like a radical idea.)

Bruce.

If you have the money get them all. But adding solar after a first install is just about impossible!!

How long were your lights out for? IMO, is hours longs worth tens of thousands of dollars? The issues with batteries? Is a tesla worth the money to me, nope, but if I could get one free.

 

[swedge]

Oddly enough, I have the Grid Charge feature, but not the Export Everything

I am in the same boat, Export options are missing. Tesla Energy Support got it up to Tier 2 who looked at my account with the app and said it was there! But they do this not by logging in not with my email and password, but rather using an authentication bypass they call "masquerade". I had an earlier, similar problem like this, an option missing from the app, and once they understood that they were not seeing what I was seeing, they were able to fix it. Hopefully that'll happen again soon. I'll try to get a description of what they do, or the name of someone who knows the solution so I can pass that along for others.

In the mean time, if anyone does get Support to turn on the Export feature, please share the name of the agent.

SW

 

[bmah]

If you have the money get them all. But adding solar after a first install is just about impossible!!

How long were your lights out for? IMO, is hours longs worth tens of thousands of dollars? The issues with batteries? Is a tesla worth the money to me, nope, but if I could get one free.

We had no particular issues getting Powerwalls added to our existing solar, except for delays in getting PTO (during which the Powerwalls were operating normally). According to the statistics in the mobile app, we've had a total of 8 days of outage, so a little under 200 hours of outage since commissioning. The longest outage event was 3 days. You seem to imply that the only benefit we got from having Powerwalls was backup protection, but we bought ours originally for cost savings. They continue to perform in that role every day.

I'm quite happy with my investment in battery storage. As I wrote earlier, everyone's needs are different, so I would not claim that this approach is good for everyone.

(And I'm conscious of the fact that this is deviating somewhat from the thread topic, apologies for contributing to that topic drift.)

Bruce.

 

[sunwarriors]

My thoughts are first, just get AS MUCH solar on your roof, period. Does not matter direction! This is the return.

My next thought is I would not buy batteries. I am looking at the first EV that will support v2h. Much better return. Ford 150? Leaf? I just told a person today, IMO, batteries are a waste of money. They have done nothing for me to save money. I save because I have tons of solar. I have not had a power outage for like what 3 years.

Yeah, I already stuck as much solar panels as possible outside of putting panels on the north or east facing sides. I didn't want the hassle of trying to get a future installer to deal with the old install which seems like a headache and 2 systems.

We have very stable power here, but I think the long term non-care of whatever the IOUs can charge is nice piece of mind. They can jack up rates to $1.00 in the middle of the night from 7pm - 6am and since we use zero from them at night, it wouldn't affect us, but folks without batteries could be taken advantage of.

Some folks like that control/power vs. missing the $20k or so (more/less depending on SGIP and tax credits). At the end of the day, I think the tens of thousands just end up being a number in a bank account...You won't miss it much, but 1 massive power event will make some folks feel it was all worth it (I'm still waiting for my 1 outage ).

 

[h2ofun]

Yeah, I already stuck as much solar panels as possible outside of putting panels on the north or east facing sides. I didn't want the hassle of trying to get a future installer to deal with the old install which seems like a headache and 2 systems.

We have very stable power here, but I think the long term non-care of whatever the IOUs can charge is nice piece of mind. They can jack up rates to $1.00 in the middle of the night from 7pm - 6am and since we zero at night, it wouldn't affect us, but folks without batteries would be taken advantage of.

Some folks like that control/power vs. missing the $20k or so (more/less depending on SGIP and tax credits).

I put a ton on my north facing. They kick butt 8 months of the year.

I am not saying batteries at not cool, but I see so many not putting the first set of money to max out the panels they can get approved, including north and east facing, depending on any shading. I have a east side I did not put panels on since my house shaded it most of the time.

 

[BruceHulkBanne]

I have 2 Tesla Powerwalls and Tesla Solar Panels as well. I have set my Tesla app on time based control, this allows me to use the Powerwall during peak hours.
I leave a reserve of 40% in my Powerwall, for emergency purposes. From late April to September we get plenty of sunshine, so the Solar panels are able to charge the Powerwalls and also power my home in the day.

My question is, should I set the Powerwall to charge from the grid as well? I can't decide if this would make financial sense for me. PG&E buys back electricity at $0.04 kwh, which is peanuts, this their peak rates are $0.54, and off peak at $0.11.

If I do not charge the Powerwall from the grid, then if power goes out, I have a minimum of 40% of Powerwall to get me through the night, until the sun rises.
But if I set the Powerwall to charge from the grid, the Powerwall starting charging at 11PM (off peak start) and completed by 1AM.

 

[jjrandorin]

I have 2 Tesla Powerwalls and Tesla Solar Panels as well. I have set my Tesla app on time based control, this allows me to use the Powerwall during peak hours.
I leave a reserve of 40% in my Powerwall, for emergency purposes. From late April to September we get plenty of sunshine, so the Solar panels are able to charge the Powerwalls and also power my home in the day.

My question is, should I set the Powerwall to charge from the grid as well? I can't decide if this would make financial sense for me. PG&E buys back electricity at $0.04 kwh, which is peanuts, this their peak rates are $0.54, and off peak at $0.11.

If I do not charge the Powerwall from the grid, then if power goes out, I have a minimum of 40% of Powerwall to get me through the night, until the sun rises.
But if I set the Powerwall to charge from the grid, the Powerwall starting charging at 11PM (off peak start) and completed by 1AM.

That "PGE buys back electricity at .04kwh" is only true at true up, meaning that is what happens at the end of the 12 month period. You get credit for it at the rate in force when its generated. You only get PAID 4 cents a kWh at the end of the 12 month period, if you happen to be a net generator at the end of that 12 month period.

 

[Kcarver]

Are you with SRP, or APS? SRP doesn't have the free nights plan.

I’m on SRP and turned the Grid Charging to “Yes” with reserved set greater than my PW SOC. I saw that PW did start charging from grid. So this feature is working in AZ.

 

[Shwood]

I still have the Grid Charging Option available…. I haven't tried since I did take the ITC.

Sorry to backtrack but, having read through 16 pages of thread, the ITC issue has been danced around but the elephant-in-the-room question doesn’t seem to have been answered (at least not in a manner I understand):

For a net user of energy that simply wants to grid charge the PW during off hours for use during peak hours (not export everything), does the utility company have any means of identifying this (like the ability to peer into inverters… or Jedi mind control, eye of Sauron, etc.)? They would see a shift to off-peak energy use (which, after all, is the goal of TOU, so pretty innocuous), but no change in overall use or production. Unless they have free time to monitor the system in detail (not just the ins and outs), there shouldn’t be much to flag an account, correct?

 

[jjrandorin]

Sorry to backtrack but, having read through 16 pages of thread, the ITC issue has been danced around but the elephant-in-the-room question doesn’t seem to have been answered (at least not in a manner I understand):

For a net user of energy that simply wants to grid charge the PW during off hours for use during peak hours (not export everything), does the utility company have any means of identifying this (like the ability to peer into inverters… or Jedi mind control, eye of Sauron, etc.)? They would see a shift to off-peak energy use (which, after all, is the goal of TOU, so pretty innocuous), but no change in overall use or production. Unless they have free time to monitor the system in detail (not just the ins and outs), there shouldn’t be much to flag an account, correct?

Do you not have solar? If you dont, thats correct. If you do, the utility would see an increase in export because the powerwalls would be full from off peak energy.

 

[BruceHulkBanne]

Sorry to backtrack but, having read through 16 pages of thread, the ITC issue has been danced around but the elephant-in-the-room question doesn’t seem to have been answered (at least not in a manner I understand):

For a net user of energy that simply wants to grid charge the PW during off hours for use during peak hours (not export everything), does the utility company have any means of identifying this (like the ability to peer into inverters… or Jedi mind control, eye of Sauron, etc.)? They would see a shift to off-peak energy use (which, after all, is the goal of TOU, so pretty innocuous), but no change in overall use or production. Unless they have free time to monitor the system in detail (not just the ins and outs), there shouldn’t be much to flag an account, correct?

What’s wrong with charging the PW from the grid during off peak hours?

 

[BruceHulkBanne]

That "PGE buys back electricity at .04kwh" is only true at true up, meaning that is what happens at the end of the 12 month period. You get credit for it at the rate in force when its generated. You only get PAID 4 cents a kWh at the end of the 12 month period, if you happen to be a net generator at the end of that 12 month period.

What good is the credit at the rate in force if they are paying 4 cents no matter the time? I don’t quite follow.

 

[Shwood]

Do you not have solar? If you dont, thats correct. If you do, the utility would see an increase in export because the powerwalls would be full from off peak energy.

I do; however, the increase in export during peak hours still would be offset by use later in the day so would simply be shifting use toward off peak hours… as would be anticipated with any solar system on a TOU plan. The effect might be a little more dramatic if charging from the grid, but the pattern is nothing unique that would suggest charging from the grid.
Do utilities really have time/resources to spend on monitoring/investigating this when a) it benefits them and b) it is the IRS that actually cares?

 

[Shwood]

What’s wrong with charging the PW from the grid during off peak hours?

If you took the ITC towards the PW it is supposed to be charged with 100% PV. If you didn’t take the ITC, no worries.

 

[swedge]

Do utilities really have time/resources to spend on monitoring/investigating this when a) it benefits them and b) it is the IRS that actually cares?

PG&E in California only collects power import and export data by the hour, but they do allow charging from the grid.

For most residential systems with solar, they also estimate the maximum amount the customer’s installed solar could produce each month, and limit export credit to that amount. This prevent you from buying cheap off peak power from them and then selling it back to them at higher peak price.

If you import mostly off-peak,and export some solar at peak, it is possible to get more $ credit for exported solar than you owe for imported power, but at the annual true-up they just take away that excess credit. After taking away that net time of use credit, If your total exported power for the year is more than your total use for the year, they do give a small credit for that.

 

[ZBB]

Are you with SRP, or APS? SRP doesn't have the free nights plan.

I’m no longer in AZ…. Now in Houston where there are multiple providers with free nights plans. The problem is that they can be tricky to compare. The one we are on has off-peak from 8pm to 6am. Other plans are 9p-9a or 8p to 5a. The other big difference is that some plans still charge for delivery at night while others also include credits for that.

In TX, the deregulation results in the local TDU (“Transmission and Delivery Utility, Centerpoint in the Houston area) charges $4.39 per month connection fee and just under 4 cents per kWh imported to the house. The REP (“Retail Electricity Provider”, which is an open market with many providers) charges for the remainder of the cost and bills the consumer. The plan we are on does not pass through the delivery charge for grid use during the nighttime off-peak — which works well for us. Our bills each month are for the $4.39 connection fee plus a few kWh that we pull during the day — 10-15 kWh per month. In April, we pulled about 900 kWh from the grid with 99% of that at night. We also exported just over 900kWh of excess production — sold back at $0, but that basically offset the nighttime draw.

This works for us….