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Optimising Powerwall charging [outside the US]

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I’m in Australia and am looking to optimize my Powerwall 2 settings. I’m specifically looking for software or an app that can enable smarter charging.

We’re coming out of winter so my solar output (4.2kW system) is increasing. I’m with an electricity retailer (Amber) that offers a variable tariff based on time of use and the market wholesale price. Over the past few months I’ve seen the 30 minute price I pay for electricity vary from 0 up to $8/kWhr. However, the 10 month average price I’ve paid is 14c/kWhr. Typically the prices I pay hover around 10-20c during the day, increase to 25-30c between 4pm and midnight and then drop back to around 10-15c overnight. As such, over winter, I’ve had my Powerwall set to cost savings with my peak set at 4pm-12.30pm and off peak set to 2am-6am. On a good day, the PW will charge overnight, then, during the day, I can run off solar and make it through to 4pm with the PW at 100%. From 4pm onwards I just run off the PW. Therefore the only power I take from the grid is at the cheapest prices (2am-6am).

However, with the days getting sunnier I’m increasingly generating more power during the day than I need and it’s going back into the grid. The time of use tariffs I’m on apply to exports too. Today, a very sunny day with lots of renewables in the grid, the solar export price actually went negative - I was being charged to export power.

As shown in the image, last night I took 10.9kWhr from the grid to charge the battery. But during the day I put 8.2kWhr back into the grid. Ideally, I should have only partially charged the PW last night and then used the solar to top it up during the day.

I knew today was going to be sunny and could’ve predicted that I only needed a partial charge of the PW. It’s going to rain and be colder tomorrow so tonight I would like to fully charge the PW.

My question then is, how can optimize this? Is there any software or app I can run to give me more control over the PW?
 

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Welcome to TMC,

I added the [outside the US] qualifier to your thread title, because there may be more options available to you outside the US than we have here. For example, Inside the US we can not charge from the grid at all on user demand, without basically performing some steps to log into the equipment as if we were an installer, and changing settings which are not user facing.

Its my understanding that there may be more flexibility outside the US, so I added the qualifier to your thread title. Note that any discussion of "charging from the grid" or "more control of powerwalls" many times brings responses about "what SHOULD be able to be done" instead of " what IS able to be done, with current configurations, etc".

I mention this to preemptively ask people to focus on what "can" be done, not what "should" be able to be done. I am not aware of what can be done, but hopefully you get some feedback.
 
Welcome to TMC,

I added the [outside the US] qualifier to your thread title, because there may be more options available to you outside the US than we have here. For example, Inside the US we can not charge from the grid at all on user demand, without basically performing some steps to log into the equipment as if we were an installer, and changing settings which are not user facing.

Its my understanding that there may be more flexibility outside the US, so I added the qualifier to your thread title. Note that any discussion of "charging from the grid" or "more control of powerwalls" many times brings responses about "what SHOULD be able to be done" instead of " what IS able to be done, with current configurations, etc".

I mention this to preemptively ask people to focus on what "can" be done, not what "should" be able to be done. I am not aware of what can be done, but hopefully you get some feedback.
Thanks! I agree, I also have plenty of ideas of what "SHOULD" be done. Even Tesla adding the option of multiple peaks in the scheduling would be a huge step forward. I am keen to hear if anyone has found a solution, this shouldn't be hard.
 
One thing I am aware of, is a utility developed by one of our posters here. I dont use it, so I dont know the nuts and bolts around how it is setup, etc.

Here is one of the threads I remember about trying to setup powerwalls around utility demand plans:


Here is a short thread about the utility:


Here is a link to the direct website for said utility. Note that I am NOT promoting this utility, have no idea how well it works, etc etc. I just remember one of our members programed for the express purpose of changing powerwall states to better work for themselves and others around different TOU times etc:

 
One thing I am aware of, is a utility developed by one of our posters here. I dont use it, so I dont know the nuts and bolts around how it is setup, etc.

Here is one of the threads I remember about trying to setup powerwalls around utility demand plans:


Here is a short thread about the utility:


Here is a link to the direct website for said utility. Note that I am NOT promoting this utility, have no idea how well it works, etc etc. I just remember one of our members programed for the express purpose of changing powerwall states to better work for themselves and others around different TOU times etc:

Thank you so much, that is very interesting. I will explore it. Thank you for taking the time to pull together all those threads.
 
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