Tesla App Utility plan configuration: Multiple Peaks, Buy/Sell Behavior, etc

[nfarina]

Here's a solar tariff document that I found for Pacific Power: https://www.pacificpower.net/conten...Service_Optional_for_Qualifying_Customers.pdf

Wow, I can't believe I never saw this document! Thanks for finding that - and yes it does seem to confirm what I see on my bill, although I admit I haven't done extensive analysis to confirm this behavior. The language is interesting, it sounds a lot like how short/long term capital gains work for taxes.

I found another interesting suggestion in another thread that suggested all-off-peak weekends were the real problem:

One thing to note is that in Cost Saving, it will try to optimize the cost savings and does some things that I didn't like. For example, on Fridays it will start discharging in Shoulder to get SOC low for Off peak Weekend charging. So I eliminated all shoulder in my settings

This seems to match my behavior - Powerwall discharged continuously after the last peak time on Friday evening to "make room" for future weekend solar (which didn't happen because winter). So I tried adding a little 30 minute "peak time" for weekends to see if that fixes the problem, and put my sell rates back to $0.

 

[Jeremy3292]

Considering ordering a 10 kW solar + 2 PWs. However, I found that Duke Energy has a pretty interesting solar TOMU plan here in South Carolina. I want to make sure I understand if It is possible to manage my usage appropriately in the app based on this weird plan.

Plan highlights:

1. TOMU periods:
   • Peak: 6-9pm M-F and 6-9am M-F during Dec/Jan/Feb
   • Super off peak: 12am-6am March-Nov
   • Off peak: all other times that aren’t peak or super off peak
2. Energy used and energy sent to the grid is netted every month for each TOMU period
3. Any monthly net excess energy generated within each TOMU period is paid $0.03 per kWh
4. Minimum $30 bill before any excess energy credits are applied

Best use scenarios:

1. Avoid peak period at all times. Use Powerwalls during this time. Likely very little solar to offset any grid usage during this time except maybe during long summer days. Same for the winter 6-9am additional peak period.
2. Avoid super off peak period. Use Powerwalls during this time. No solar during this time to offset any usage, so I would be billed for all usage during this time. Zero benefit to using this period that I can think of.
3. Use off peak period as much as possible. Virtually all solar power will be generated during this time.
   • Power house, charge car, charge powerwalls, etc
   • Send any excess energy back to the grid to offset any future grid usage that may occur during the month in this TOMU period
   • Will hopefully generate monthly bill credits in this TOMU period

Is it possible to account for this in the app some way? Probably will take some playing around with…

 

[Gwgan]

The app should be able to handle that TOU scenario but be sure to put a 15% difference between buy and sell prices during each period to let Powerwall know if it is a good time to trigger.
Since you have suntime offpeak you can finesse charging car and PW with solar using ChargeHQ (in beta).
https://chargehq.net/get-started

 

[Gwgan]

New subtopic: when did the app link the TOU plans between Powerwall and Vehicle? Now when I save one there is an alert that it will change the plan in the linked product.

Note that I’ve yet to see the edits in one product actually appear in the rate plan for the other but it could be slow to update.

For Powerwall, Tesla recommended an artificial plan to get the desired discharging pattern but I had been using the actual rates for the car so the car charging value estimates would be correct.

Irks me that we need to fudge a rate plan at all but that’s a rant for another time.

 

[jgleigh]

My utility recently launched an interesting EV ToU plan and need advice on the best way to setup the app to make the best use of it.

Peak: 5 AM to 10 PM, buy $0.12/kWh, sell $0.05/kWh
Off-Peak: 10 PM to 5 AM, buy $0.07/kWh, sell $0.05/kWh

The caveat is that the Off-Peak discount is only good for the first 400kWh.

Powerwalls are setup to charge from solar and only export solar.

The issue I'm seeing is that during Off-Peak it only uses the grid and never pulls from the Powerwall even when the Powerwalls have plenty of extra charge stored.

Would changing the Off-Peak to Mid-Peak make better use of the stored energy in the Powerwalls but not solely pull from the grid during that time period?

 

[miimura]

Since they added prices to the TOU settings in the Tesla app, I don’t think the period matters much any more. The behavior is mostly dependent on the prices. In other words, if you have two rate periods per day, I don’t think it matters whether you use Off-Peak and Mid-Peak versus Off-Peak and Peak.

 

[Gwgan]

“Off-Peak: 10 PM to 5 AM, buy $0.07/kWh, sell $0.05/kWh” as if there would be any solar to sell at those hours.

PW will do what it can to prevent buying at peak prices which may mean not buying at off peak prices to keep as much in the battery to spend during peak times. Their idea of “extra” may not be what you think it is.

 

[jgleigh]

“Off-Peak: 10 PM to 5 AM, buy $0.07/kWh, sell $0.05/kWh” as if there would be any solar to sell at those hours.

Supernova?

 

[jgleigh]

New settings. Looks like this may do what I want. Going to try it for a few days and see what happens.

Peak: 5 AM to 10 PM, buy $0.12/kWh, sell $0.00/kWh
Mid-Peak: 10 PM to 5 AM, buy $0.07/kWh, sell $0.00/kWh

Off-Peak uses the grid exclusively regardless of any price settings compared to Mid-Peak which will use both the battery and the grid. Tesla kind of implies this in their manual.

"This home’s off-peak period starts at midnight. There’s a Tesla vehicle now charging based on set charging schedules to maximize the use of low-cost energy. Even if Powerwall had stored energy available, Powerwall would not be programmed to discharge, even to help charge the Tesla vehicle, during the off-peak period."

I had to set the sell prices to zero so it will use the battery more during Mid-Peak instead of prioritizing exports during Peak time.

 

[MJ_CA_2019]

Does Tesla update the pricing in the rate plans that exist in the app?
Or are we expected to do that ourselves as the rates change?

I'm on E-TOU-B and the pricing in the app appears to be vastly different from the most recent posted tariff sheet from PG&E.

 

[miimura]

I have never seen rates automatically update in the Tesla app. I have manually entered my PG&E rates (EV2-A) that took effect on January 1st.

 

[Snowball316]

I have never seen rates automatically update in the Tesla app. I have manually entered my PG&E rates (EV2-A) that took effect on January 1st.

Same.

TLDR. Sorry. It might be buried somewhere on this forum

PG&E for Bay Area just updated their pricing for 2024 and this is my first season using Tesla Solar and Tesla app together. I found my buy price for EV2, but what is my sell price ? Thanks in advance !

 

[miimura]

Same.

TLDR. Sorry. It might be buried somewhere on this forum

PG&E for Bay Area just updated their pricing for 2024 and this is my first season using Tesla Solar and Tesla app together. I found my buy price for EV2, but what is my sell price ? Thanks in advance !

I am on NEM 2 and have Powerwalls. So, I set the sell price at 7c/kWh below the buy price. That is about 3c/kWh for NBCs (Non-Bypassable Charges) and about 4c/kWh for 10% round trip loss on the PWs. If you don't have PWs, then I would just reduce by 3c/kWh for each period between buy and sell.
The reason that I add the round trip loss is that I want to encourage the PWs to slow down the charging to use surplus solar instead of all solar when there is sufficient generation to reach 100%. Otherwise, it tends to fill the PWs from all solar as fast as possible, then export surplus solar. If is allowed some of the solar to go directly to the house while it was charging, it would export less and incur less NBCs.

 

[Snowball316]

I am on NEM 2 and have Powerwalls. So, I set the sell price at 7c/kWh below the buy price. That is about 3c/kWh for NBCs (Non-Bypassable Charges) and about 4c/kWh for 10% round trip loss on the PWs. If you don't have PWs, then I would just reduce by 3c/kWh for each period between buy and sell.
The reason that I add the round trip loss is that I want to encourage the PWs to slow down the charging to use surplus solar instead of all solar when there is sufficient generation to reach 100%. Otherwise, it tends to fill the PWs from all solar as fast as possible, then export surplus solar. If is allowed some of the solar to go directly to the house while it was charging, it would export less and incur less NBCs.

Thanks for the quick response.

I believe I have NEM 3 (Since I enrolled after April) and have (2) PW+. What should I input? Thanks again !

 

[miimura]

Thanks for the quick response.

I believe I have NEM 3 (Since I enrolled after April) and have (2) PW+. What should I input? Thanks again !

I have not looked into the Net Billing Tariff enough to know a dollar amount to put in the Sell price schedule. I would be interested to see your bill since the NBT only took effect in November. Did you get a letter about the new billing? If your PTO was before November, then you should have been billed on NEM2 and then the December bill should be on the new tariff. PM me if you want help figuring out the billing.

 

[skepticcyclist]

Been playing with the pricing a bit to see how I can get my charging and discharging behavior to act like the old balanced setting that used to be available. Here is what I discovered

Non-peak time:

• Old Cost - Savings: Set both the buy and sell price the same - All solar will first go to the battery until it is charged. Then solar will go to the house with excess to the grid.
• Old Balanced setting: Set the sell price one cent less than the buy price - Solar will first go to the home with excess going to the battery until the battery is full.

Peak time

• Old Cost - Savings: Set both the buy and sell price the same - All solar will go to the grid and your battery will solely supply the home until it reaches the reserve limit.
• Old Balance setting: Set the sell price one cent less than the buy price - Solar will still go to the home, excess to the grid, and supplemented by the battery as needed. Both solar and battery feed the home until solar production stops, then the battery will solely supply the home until your reserve level is met.

 

[C DM]

I have never seen rates automatically update in the Tesla app. I have manually entered my PG&E rates (EV2-A) that took effect on January 1st.

This is rather odd. What's the point of Tesla including various providers and plans and rates as options in their app if they (at last sometimes) won't update the numbers to reflect reality.