Tesla Powerwall 3 set up.

JKenH

Hi,

I thought I would start a new thread for Tesla Powerwall set up discussion. 



 

JKenH

I am wondering if anyone can help me to set up my Powerwall 3 to take advantage of Octopus Agile cheap rates to charge. I had read that the answer was to use the Netzero app so I purchased the app - paid version. 

Unfortunately I cannot work out how to do this. I can’t find any instructions on the Netzero app and searching on the net says

Steps to add Octopus Agile in Netzero:

1. Open Netzero: Launch the Netzero for Powerwall app on your device.
2. Go to Settings: Navigate to the 'Settings' menu within the app.
3. Select Utility Rate Plan: Find and select the 'Utility Rate Plan' option.
4. Enter Details: Input your Octopus API Key and your Octopus Energy Account Number into the respective fields.
5. Enable Automation: Turn on the "Automate Intelligent Octopus Go" (or similar Agile/Intelligent Octopus setting).
6. Confirm: Press 'Confirm' or 'Save' to link your account. 

The app will then automatically fetch the daily Agile prices and schedule charging (for compatible devices like Tesla Powerwalls or smart chargers) during the cheapest slots, preventing discharge during expensive times. 

Unfortunately in settings there is no option to select "utility rate plan" in settings so I cannot progress. Can anyone who has successfully set up Agile on the Netzero help me please? 

Edit: after more than an hour of searching for and failing to find this elusive”utility rate plan”, messaging the app developers and posting on here I went back into the app and by magic it was now there. So, hopefully, problem solved.

Edit 2: Netzeri came back to me with

Thanks for the report. You might just need to restart the Netzero app -- swipe up to get the list of apps, swipe up on the app to close it, and restart. Let us know if you that doesn't work for you.

Good to know they do respond. 

QrizB

I don't have a Powerwall but hope to learn more about them by reading this thread as it develops

JKenH

QrizB said:

I don't have a Powerwall but hope to learn more about them by reading this thread as it develops

It may be a little while before you learn anything useful from my comments. I did manage to get the NetZero app to populate the Tesla app with my Agile tariff  but then the Powerwall, although saying I was now on the Agile tariff didn’t charge up when rates were 3-4p/kWh in the early hours of Wednesday morning and didn’t discharge at 4pm either. It didn’t charge up last night either so I removed the Agile tariff and created my own “tariff” which improved things a little. It seems like it is asleep unless you poke it then it springs into action. 

Apparently it can take a couple of weeks to go through a learning process. This is what Google AI says:

Yes, the Tesla Powerwall 3 software needs time to learn your home's energy usage patterns, 

often taking about a week or so (up to 7-14 days) to adapt and work optimally, especially with Time-Based Control (TBC) or changes in tariffs/usage (like adding a heat pump). During this initial period, its behavior (charging/discharging) can seem unintuitive as it gathers data and calibrates for your specific habits, but it generally settles into an efficient rhythm once trained. 

What to Expect During the Learning Phase:

• Time-Based Control (TBC): For the first 7 days, TBC might not behave as expected as it learns your solar production and consumption, sometimes charging or discharging at seemingly odd times.
• Adaptation: The system optimizes based on weather forecasts and your real-time energy use, so changes (like a sudden cold snap or new appliance) require it to re-learn.
• Calibration: Powerwalls also undergo periodic calibration, which is normal and can take up to 24-48 hours, during which performance might vary. 

It is all very well just letting it run but when it doesn’t come on at peak times it could get expensive. I posted a review (perhaps prematurely)of the NetZero app on the App Store 12 hours ago but it hasn’t appeared yet. If and when it does appear I will post a copy here along with the developer’s response.

Edit: The NetZero app generally receives glowing reviews; I would imagine most people have had their Powerwall a little time before downloading the app so the battery software already understands the user’s usage pattern and things would go more smoothly. Maybe Agile’s dynamic pricing is a bit too complicated for the Tesla software to cope with on a new installation and something like Octopus Go (dumb version) would be a better place to start. 

greenbee

It sounds similar to MyEnergi Libbi from a charging POV (no facility to automate discharge with Libbi). Works fine with simpler tariffs, but doesn’t always pick the best slots for Agile - and if Agile data is late, that can cause problems too. So I end up setting times manually on a daily basis which isn’t ideal (and I do sometimes forget/get it wrong/fail to account for changes in the weather forecast. I’m sure I could improve this process using Home Assistant or building an AI agent, but  don’t have the spare brain power right now. Hopefully, it’s just a of waiting for software (OEM or third party) to catch up with consumer expectations - and maybe some of those developers somewhere are actually listening to what we want!

JKenH

I am getting a bit more used to how the PW3 behaves and, perhaps more importantly, it seems to be getting used to me. After the initial disappointment with its response to Agile I programmed in my own”tariff” with four different price bands from super off peak to peak then broke the day up to 7 or 8 time slots and allocated a rate to each. It was necessary though for me to also set separate export rates for each time slot because the PW3 on time based control is focussed on saving money and how it responds to any given import price will depend on the export price at the time. Because the PW3 also takes into account charging losses there has to be a clear margin between import and export. (The rates I entered while reflective of typical time of day pricing are of course are a completely artificial construct and don’t reflect what I pay - I just wanted to programme the PW3 to test how it responds). Over around a 30 hour period the PW3 responded exactly how I wanted it to, charging and discharging perfectly. 

That exercise completed, yesterday evening I put the PW3 back on the Agile tariff. Having gone to bed with 42% charge I woke up with 44%, it having added 0.4kWh to the battery around 5am. Agile prices had been virtually flat through the night between 14p and 15p so with a sunny day forecast I was not surprised that the PW3 didn’t bother this charging. When rates at breakfast went up to around 17p it kicked in and took the house load. At 8.30 when the import rate went up to 17.3p the battery stopped discharging and we went back to the grid - the reason, being, I imagine, that solar generation had started. It was only around 0.2 kW at 8.30 as it melted the frost from the roof but by 9am had reached 0.8kW. The decision whether to discharge or use grid power seems to be made on the half hour and I think it sticks with that rather than being based on load or solar PV at any point during the hour. Obviously it won’t discharge if the solar PV is covering the load and it seems to make a guess, not just on the load/PV at the start of the hour but what it thinks it might be. This I presume then lets it charge the battery with any excess solar rather than wasting it to the grid. 

Having said that, as I write this at 9.10 the system is generating 0.9kW and sending 0.2kW to the battery and 0.7kW to the grid. The import rate is currently 16.8p. 

At 9.12 1kW of PV is being produced and 0.2 is going to the battery and 0.8kW to the grid. At this point my other panels have just taken over the house load. The PW3 cannot see those panels, just the net inflow of generation from them less the house load. 

At 9.15 the new solar panels are generating 1.1kW and with 0.1 from the house 1.2kW is being sent to the grid. Battery SoC is 38%.

There’s still a lot to learn. 

Update 11.25am

This does seem a bit weird. The battery SOC has fallen from 38% to 36% over the last couple of hours despite continuous (hazy) sun. I have both ASHPs running in the house which are taking what the house roof is producing and the new panels above the garage are supplementing that with 0.2kW. Only 0.2 kW is going into the battery and 1.4kW going to the grid. We are paying 15p import until noon then for 3 hours the import rate drops into the 14ps before rising again at 3pm. Is the PW3 waiting for lower import rates rather than forgoing export at 15p or is the PW3 thinking it can tough it out through tonight’s peak 4-7pm with just 36%?

thevilla

"The PW3 cannot see those panels". I would think that would be easy to change with an additional CT clamp if you wanted to and they're not a massive distance apart.

You've already invested in your app but I wondered if you're aware of predbat which runs on home assistant. Maybe more of a faff than you'd like but it's highly configurable and worth bearing in mind if you remain unconvinced with your current setup. 

https://springfall2008.github.io/batpred/what-does-predbat-do/

NedS

JKenH said:

Edit 2: Netzero came back to me with

Thanks for the report. You might just need to restart the Netzero app -- swipe up to get the list of apps, swipe up on the app to close it, and restart. Let us know if you that doesn't work for you.

Good to know they do respond. 

The developer is very active and does respond to queries. He is active on Reddit and some Facebook PW forums too, I think.

NedS

JKenH said:

I am getting a bit more used to how the PW3 behaves and, perhaps more importantly, it seems to be getting used to me. After the initial disappointment with its response to Agile I programmed in my own”tariff” with four different price bands from super off peak to peak then broke the day up to 7 or 8 time slots and allocated a rate to each. It was necessary though for me to also set separate export rates for each time slot because the PW3 on time based control is focussed on saving money and how it responds to any given import price will depend on the export price at the time. Because the PW3 also takes into account charging losses there has to be a clear margin between import and export. (The rates I entered while reflective of typical time of day pricing are of course are a completely artificial construct and don’t reflect what I pay - I just wanted to programme the PW3 to test how it responds). Over around a 30 hour period the PW3 responded exactly how I wanted it to, charging and discharging perfectly. 

This is essentially how I run my PW3, although I'm on the Cosy tariff which is a lot easier to manage. If I were on Agile, I would do as you have done and manually assigning slots as either 'cheap' or 'mid' or 'expensive' throughout the day. You know Agile is generally cheap from 22:30 through to 5am, higher through to 10 or 11am, cheaper through to 4pm, and then expensive until later in the evening. You can probably work out the slots you'd like to charge in / draw from the grid and manually update each day - or pay the monthly subscription to NetZero and let it manage it for you (but I doubt you will save the subscription fee?) 

I set the 3 Cosy cheap slots as Off-Peak (15p) and set all other times as Peak with an artificially high import price of 200p - in other words DO NOT import outside of the cheap rate slots, only run from the grid or import electricity in the 3 cheap slots. Hopefully this is clear enough that even the Tesla AI can be in no doubt! My average import price is effectively equivalent to the Cosy cheap rate price (~14.8p for me).

If you have enough battery capacity to run your home like this, Cosy may be an easier option than Agile unless you think you can achieve a lower average price on Agile over winter. I keep an eye on the Agile pricing, but mostly the lowest prices have been around the same or higher than Cosy, and mostly only occur overnight when we use least due to overnight set backs on the heating, plus Cosy with it's 3 spaced out cheap slots allow us to recharge 3 times per day and cover 40-50kWh per day usage from a single 13.5kWh PW3. So for us, I think on average Cosy is cheapest in winter and gives certainty of pricing.

You should absolutely consider switching to Intelligent Octopus Flux (IOF) in summer as this is by far the most lucrative tariff when you are a net exporter. Last summer we averaged 25-26p for our excess exported electricity and then import at ~15p in winter giving great leverage. We switch in around April and back to Cosy in October, and the points we become net exporters / net importers, corresponding roughly to the time the heating goes on/off. This arrangement requires virtually no management or input from me and I can just let the PW3 get on with it, plus I do not need to pay any subscription fees for the NetZero app.

JKenH

NedS said:

JKenH said:

I am getting a bit more used to how the PW3 behaves and, perhaps more importantly, it seems to be getting used to me. After the initial disappointment with its response to Agile I programmed in my own”tariff” with four different price bands from super off peak to peak then broke the day up to 7 or 8 time slots and allocated a rate to each. It was necessary though for me to also set separate export rates for each time slot because the PW3 on time based control is focussed on saving money and how it responds to any given import price will depend on the export price at the time. Because the PW3 also takes into account charging losses there has to be a clear margin between import and export. (The rates I entered while reflective of typical time of day pricing are of course are a completely artificial construct and don’t reflect what I pay - I just wanted to programme the PW3 to test how it responds). Over around a 30 hour period the PW3 responded exactly how I wanted it to, charging and discharging perfectly. 

This is essentially how I run my PW3, although I'm on the Cosy tariff which is a lot easier to manage. If I were on Agile, I would do as you have done and manually assigning slots as either 'cheap' or 'mid' or 'expensive' throughout the day. You know Agile is generally cheap from 22:30 through to 5am, higher through to 10 or 11am, cheaper through to 4pm, and then expensive until later in the evening. You can probably work out the slots you'd like to charge in / draw from the grid and manually update each day - or pay the monthly subscription to NetZero and let it manage it for you (but I doubt you will save the subscription fee?) 

I set the 3 Cosy cheap slots as Off-Peak (15p) and set all other times as Peak with an artificially high import price of 200p - in other words DO NOT import outside of the cheap rate slots, only run from the grid or import electricity in the 3 cheap slots. Hopefully this is clear enough that even the Tesla AI can be in no doubt! My average import price is effectively equivalent to the Cosy cheap rate price (~14.8p for me).

If you have enough battery capacity to run your home like this, Cosy may be an easier option than Agile unless you think you can achieve a lower average price on Agile over winter. I keep an eye on the Agile pricing, but mostly the lowest prices have been around the same or higher than Cosy, and mostly only occur overnight when we use least due to overnight set backs on the heating, plus Cosy with it's 3 spaced out cheap slots allow us to recharge 3 times per day and cover 40-50kWh per day usage from a single 13.5kWh PW3. So for us, I think on average Cosy is cheapest in winter and gives certainty of pricing.

You should absolutely consider switching to Intelligent Octopus Flux (IOF) in summer as this is by far the most lucrative tariff when you are a net exporter. Last summer we averaged 25-26p for our excess exported electricity and then import at ~15p in winter giving great leverage. We switch in around April and back to Cosy in October, and the points we become net exporters / net importers, corresponding roughly to the time the heating goes on/off. This arrangement requires virtually no management or input from me and I can just let the PW3 get on with it, plus I do not need to pay any subscription fees for the NetZero app.

Thanks for those tips. I was thinking about IOF for the summer. Couple of questions; does the PW3 fill itself everyday from solar (when available) and does it discharge down to the back up level everyday to maximise revenue for the user or does Octopus charge and discharge it to suit its needs?

JKenH

thevilla said:

"The PW3 cannot see those panels". I would think that would be easy to change with an additional CT clamp if you wanted to and they're not a massive distance apart.

You've already invested in your app but I wondered if you're aware of predbat which runs on home assistant. Maybe more of a faff than you'd like but it's highly configurable and worth bearing in mind if you remain unconvinced with your current setup. 

https://springfall2008.github.io/batpred/what-does-predbat-do/

Thanks, that does seem a cheaper alternative to NetZero but I think it would be a bit beyond my capabilities. As I understand it, it doesn’t run natively on an iPad which is a bit of a barrier for me. We have an old iMac (more than 10 years old) in our filing room which we probably use a couple of times a month but we have to be desperate to wait 5 minutes + for it to start. I did buy a windows laptop for some motorsport related applications a few years ago and after a month gave it to my daughter. I found the NetZero automations were a bit technical so that’s the level of computer incompetence we are talking about here. 

If it won’t work on an iPad it won’t unfortunately work for me but thanks for the suggestion.