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Tesla: we need more control over our PowerWalls
- Thread starter Ulmo
- Start date
aesculus
Still Trying to Figure This All Out
I am not sure if you are using it in Cost Mode or another. For me, during the summer months where we essentially have no weather changes, it's spot on using Cost Savings Mode.
But as soon as the weather becomes a factor all holds are off and I think it does a terrible job then. I don't think weather forecasting is part of their current model. I also suspect, but don't know, is that they also normalize consumption patterns too. But really how would they be able to do anything else? If I suddenly take a trip in my car that is going to drastically offset my normal consumption, but it's a occasional and non predictable event.
Anyway I suspect their algorithms are a bit crude but when your situation (usage and weather) are fairly predictable (ie static) it seems to do a pretty good job, even sending back more power on Thursdays and Fridays then it would other days and getting my PWs charged on Saturday just before peak pricing starts.
The Issue is the TOU software algorithm.
This does not work for situations where there is a poor level of day time solar such as winter and a user is relying on supplementing the solar by topping up from the grid during cheap set off peak periods.
The algorithm works by determining the amount it will charge from the grid during the off peak period on the users peak time period usage and the the amount of solar from the previous 2 or 3 days.
This results in the powerwall playing catch-up all the time, I have an overnight off peak period and an example which regularly happens would be....
A few sunny days will result in the powerwall reducing or stopping the charge it takes from the grid during the off peak period as it is getting topped up with solar enough to get through the peak period. A following rainy dull day will have you waking to a flat battery and having to use expensive grid power all day, the next night the powerwall will still not fully charge so if the dull weather persists you will end up using expensive grid power for a second day, the powerwall will then usually fully charge the next night, and, as frequently happens, the next day will be sunny and you will have a full battery and be exporting your solar to the grid all day. This then repeats.
The peak vs off peak can be 5x more expensive so you can imagine how frustratingly this is especially as it could be so easily resolved by just being able to manually adjust the desired percentage you want the battery to charge too during the next off peak period.
I have contacted Tesla support a few times about this but they just say they’ll pass on my request.
I like many others are forced to use other methods to try to make it work by running a program to automatically send a battery reserve percentage change to try to make the battery charge during the off peak, but even this now has been scuppered by the new v4 app. I only have a 4 hour off peak period and the max charge rate if you manually adjust your reserve percentage in the v4 app is only around 1.6kwh, so I can now only ever charge my battery by about 50% during the cheap off peak period.
I don’t think things will change until it becomes more common in the US to use cheap off peak grid charging and US owners start to suffer as well and more and more complaints come in.
This does not work for situations where there is a poor level of day time solar such as winter and a user is relying on supplementing the solar by topping up from the grid during cheap set off peak periods.
The algorithm works by determining the amount it will charge from the grid during the off peak period on the users peak time period usage and the the amount of solar from the previous 2 or 3 days.
This results in the powerwall playing catch-up all the time, I have an overnight off peak period and an example which regularly happens would be....
A few sunny days will result in the powerwall reducing or stopping the charge it takes from the grid during the off peak period as it is getting topped up with solar enough to get through the peak period. A following rainy dull day will have you waking to a flat battery and having to use expensive grid power all day, the next night the powerwall will still not fully charge so if the dull weather persists you will end up using expensive grid power for a second day, the powerwall will then usually fully charge the next night, and, as frequently happens, the next day will be sunny and you will have a full battery and be exporting your solar to the grid all day. This then repeats.
The peak vs off peak can be 5x more expensive so you can imagine how frustratingly this is especially as it could be so easily resolved by just being able to manually adjust the desired percentage you want the battery to charge too during the next off peak period.
I have contacted Tesla support a few times about this but they just say they’ll pass on my request.
I like many others are forced to use other methods to try to make it work by running a program to automatically send a battery reserve percentage change to try to make the battery charge during the off peak, but even this now has been scuppered by the new v4 app. I only have a 4 hour off peak period and the max charge rate if you manually adjust your reserve percentage in the v4 app is only around 1.6kwh, so I can now only ever charge my battery by about 50% during the cheap off peak period.
I don’t think things will change until it becomes more common in the US to use cheap off peak grid charging and US owners start to suffer as well and more and more complaints come in.
RKCRLR
Active Member
In the US Tesla doesn't allow charging from the grid if you have solar unless StormWatch has been activated. And then it starts charging immediately even if it is during peak hours.
An example of how brain-dead the Tesla algorithm is….at least in the Uk where we have weather.
Last night it decided not to top up in our off-peak period starting at 00.30. I presume because the previous day we had a bit of sun and it had topped up the previous night to 50% meaning it was full by 13.00. Today however it’s completely discharged by 7.00am and there is no chance of any sun today……it clearly does not use the forecast in any way to work out what to do.
Last night it decided not to top up in our off-peak period starting at 00.30. I presume because the previous day we had a bit of sun and it had topped up the previous night to 50% meaning it was full by 13.00. Today however it’s completely discharged by 7.00am and there is no chance of any sun today……it clearly does not use the forecast in any way to work out what to do.
The problem is that no algorithm (let alone the existing one) can accurately anticipate variable weather + variable consumer use.
I'm not saying that Tesla never try to do that, just that they accept they may fail often and give users an alternative.
What is needed is the ability to manually input the percentage you want the powerwall to charge to during the off-peak period so it has sufficient charge to get you through the peak. User sets the value (given their superior local knowledge of intended use and weather conditions) and the gateway has the Powerwall charge from grid at a sufficient rate to meet the percentage within the off-peak time period.
No exotic mathematics or modelling needed, just a simple manual setting and firmware to support it. The question is how can we make this request visible to Tesla?
Obviously this setting should to be able via app and API, even better would to be able to set it locally on the gateway. Surly the recent Facebook outage demonstrates cloud-based services can't be relied upon, dependence on internet connectivity, remote servers etc. to be able to control a local device is not smart.
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I could not agree more. It seems like such a simple change. Due to yesterdays issues we ran out of charge at 7am and by 8pm we will be out again.
Much as I said earlier in this thread almost three years ago Tesla: we need more control over our PowerWalls and I sent a request to Tesla at that time. It must be near the bottom of the bin into which Tesla put these requests.
That is the quintessential statement right there.
It's a shame there's no way to take control of our PW's and let them charge from the grid ,at will, to avoid expensive peak charges. Maybe in a distant future and/or an alternate universe this might happen. In my state our "on peak" is 5-10pm and it's 43.5 cents per kWh. "Off peak" is from 10pm to 9am and is 35.2 cents per kWh. "Mid day" , as it's called, is 14.5 cents per kWh. I've heard it's much worse in California.
I don’t think you understand the issue, in the the UK you can charge a battery from the grid to avoid expensive peak charges, but the software algorithm prevents you from doing this.
Oh yes, I'm sorry. I don't think I do understand the issue. I apologize for my ignorance in the post.
That's unfortunate the software algorithm prevents us from doing this. The example pictured below is what we'd like to being doing.
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Having had a Powerwall 2 installed last Thursday to go with the PV put in earlier in September, I'm now finding all the problems outlined by JohnRatsey and others - I'm in a part of Britain that doesn't get a lot of sun at the best of times, but the behaviour of the software is ruddy awful to absolutely terrible - I'm trying to moderate my language.
But I have an additional problem - I'm on cheap rate (Octopus Go Faster) from 01.30 - 06.30, and have the 3 kW immersion heater and the dishwasher (2.7 kW) programmed to come on as late as possible in the cheap rate period - partly for safety reasons (we once had a dishwasher catch fire overnight), partly so that the hot water lasts through the day as well as it can. Unfortunately the Powerwall seems to think it incredibly clever to take over powering this 5.7 kW load after it's been on a few minutes, in preference to the grid doing the work. This is ABSOLUTELY RIDICULOUS, there is absolutely NO REASON for a battery that might have deigned to charge up earlier in the night to then waste its charge powering high consumption demand when the grid could do it at cheap rate.
I spoke to Tesla Netherlands/UK yesterday (I also have a leakage back to the grid problem due to the type of Landis and Gyr meter that was installed) and the very helpful lady told me to let the system learn my needs. So I didn't intervene early this morning, and by the time cheap rate ended my battery was down from 75% to 33% charged, leaving me little in hand for the day. For the previous nights I'd managed to defeat it by raising the stand by charge level to just above where it was, thus forcing the battery to let the grid take the load back from the battery. I don't enjoy being a poor sleeper, but I do wake up regularly in the night and I can see myself having to do this for ever, which is extremely annoying when one has just spent several thousands on what was supposed to be state-of-the-art apparatus.
As John says, we need a simple programmable option to tell the system where we want the charge level to be at the end of cheap rate, as we can make far better decisions than the Tesla algorithm. TBH I wonder if we shouldn't club together and get someone to write some unofficial software and ditch the Tesla Controls.
If I control it the system is saving me a lot of dosh and I'm pleased with it, but if I let Tesla control things I can see myself paying through the nose for its poor decisions.....
But I have an additional problem - I'm on cheap rate (Octopus Go Faster) from 01.30 - 06.30, and have the 3 kW immersion heater and the dishwasher (2.7 kW) programmed to come on as late as possible in the cheap rate period - partly for safety reasons (we once had a dishwasher catch fire overnight), partly so that the hot water lasts through the day as well as it can. Unfortunately the Powerwall seems to think it incredibly clever to take over powering this 5.7 kW load after it's been on a few minutes, in preference to the grid doing the work. This is ABSOLUTELY RIDICULOUS, there is absolutely NO REASON for a battery that might have deigned to charge up earlier in the night to then waste its charge powering high consumption demand when the grid could do it at cheap rate.
I spoke to Tesla Netherlands/UK yesterday (I also have a leakage back to the grid problem due to the type of Landis and Gyr meter that was installed) and the very helpful lady told me to let the system learn my needs. So I didn't intervene early this morning, and by the time cheap rate ended my battery was down from 75% to 33% charged, leaving me little in hand for the day. For the previous nights I'd managed to defeat it by raising the stand by charge level to just above where it was, thus forcing the battery to let the grid take the load back from the battery. I don't enjoy being a poor sleeper, but I do wake up regularly in the night and I can see myself having to do this for ever, which is extremely annoying when one has just spent several thousands on what was supposed to be state-of-the-art apparatus.
As John says, we need a simple programmable option to tell the system where we want the charge level to be at the end of cheap rate, as we can make far better decisions than the Tesla algorithm. TBH I wonder if we shouldn't club together and get someone to write some unofficial software and ditch the Tesla Controls.
If I control it the system is saving me a lot of dosh and I'm pleased with it, but if I let Tesla control things I can see myself paying through the nose for its poor decisions.....
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I haven’t read the full thread here, so it might have already been mentioned, but your post reminded me of something from this thread where some folks were using scripts to adjust the reserve settings to accommodate a double peaked rate plan. Wonder if that would be of help in your situation? Arizona Powerwall Installs
My understanding of the UK situation is that the fundamental problem is that there is no way to command grid charging. Even if you set up a box to do your own automation to use the available API, there's no way to force grid charging. It relies purely on the algorithm to think it needs grid charging.
More generally, it's a shame there is no setting for things like "Never discharge batteries during Off-Peak". It's such a simple thing that the system still screws up occasionally.
@miimura there is a way with the API to command grid charging. It requires scripts to make API requests at the right time that set the Powerwall into self-powered mode and adjust the power reserve percentage. However, in addition to needing the skills to do that and a device to run on, there are flaws:
a) It will only charge at the slow 1.7kW rate, not the 3.4kW it is capable of doing.
b) It only works when there is an internet connection AND Tesla servers are running
I currently do that every night when I have 4 hours of at off-peak and can charge my Powerwall by ~50% at most. That will not be adequate for winter when solar generation is at a minimum and power use at a max. The script has to make multiple attempts because the Tesla servers often do not respond. The changed settings values are sometimes not applied until hours later leaving the Powerwall doing the wrong thing in that period.
It would be so simple for Tesla to provide a facility to input the percentage you want the Powerwall to charge to during the off-peak period, why won't they do that?
With the current energy crisis and exponential price rises one of my friends has contacted me as he's thinking of getting a battery and knows i've got one. As far as i'm concerned the Tesla Powerwall is the best physical battery available but i couldn't recommend it to him with the current software not workable in the UK. 
Are any affected owners on here good organisers? Maybe we can send an email request as a group?
We could ask for the manual control to be added or if not request at the very least they change the wording describing the Powerwall on their website so other potential owners are not misled.
Currently it describes the Powerwalls capability as...
If your electricity rates vary throughout the day, Powerwall will charge when electricity costs are low and discharge when electricity costs are high, generating automatic savings.
I think this should be changed to...
If your electricity rates vary throughout the day, Powerwall may charge when electricity costs are low and may discharge when electricity costs are high, this will be determined by our automated software and is not user controllable, we hope this will generate automatic savings but please be aware this may sometimes not be the case.
Are any affected owners on here good organisers? Maybe we can send an email request as a group?
We could ask for the manual control to be added or if not request at the very least they change the wording describing the Powerwall on their website so other potential owners are not misled.
Currently it describes the Powerwalls capability as...
If your electricity rates vary throughout the day, Powerwall will charge when electricity costs are low and discharge when electricity costs are high, generating automatic savings.
I think this should be changed to...
If your electricity rates vary throughout the day, Powerwall may charge when electricity costs are low and may discharge when electricity costs are high, this will be determined by our automated software and is not user controllable, we hope this will generate automatic savings but please be aware this may sometimes not be the case.
Absolutely agree with the last two comments here.
As far as I can see, if one is in need of say charging the battery from 40% up to 80% then one is best advised to wake up at the start of the cheap rate period (which I often do) and select "Self Powered", then raise the slider for Back Up Reserve to 80%, and go back to sleep. This will gently charge the battery sufficiently at a rate of 1.7 kW.
However, in the depths of winter, one needs to again wake up at 01.30 (in my case), select Time Based Control, then slide the Back Up Reserve to 95%. This will fast charge the battery at 3.5 kW, and ensure that it is still pretty well fully charged at the end of cheap rate.
Simple? Convenient? State of the Art? Please imagine my real feelings on this. It's a pile of sh*t.
As Solar1920 says, we need to take on Tesla as a group on this. If the wretched Musk can get into space surely there must be someone in the organisation who can add the necessary customer option - as xWren suggests - to choose where one wants the battery to be at the end of cheap rate. And an option to forbid any battery discharge during cheap rate. Surely that's not asking much.....?
I'm going to tackle my new friend Heidi at Tesla UK/Netherlands with this suggestion tomorrow, but I think we have to find a way of getting this over to the States, as Heidi's defence of the system is simply that I should "let it learn my habits". It's clear from this thread that there are people who have been doing that for the last three years without success......
As far as I can see, if one is in need of say charging the battery from 40% up to 80% then one is best advised to wake up at the start of the cheap rate period (which I often do) and select "Self Powered", then raise the slider for Back Up Reserve to 80%, and go back to sleep. This will gently charge the battery sufficiently at a rate of 1.7 kW.
However, in the depths of winter, one needs to again wake up at 01.30 (in my case), select Time Based Control, then slide the Back Up Reserve to 95%. This will fast charge the battery at 3.5 kW, and ensure that it is still pretty well fully charged at the end of cheap rate.
Simple? Convenient? State of the Art? Please imagine my real feelings on this. It's a pile of sh*t.
As Solar1920 says, we need to take on Tesla as a group on this. If the wretched Musk can get into space surely there must be someone in the organisation who can add the necessary customer option - as xWren suggests - to choose where one wants the battery to be at the end of cheap rate. And an option to forbid any battery discharge during cheap rate. Surely that's not asking much.....?
I'm going to tackle my new friend Heidi at Tesla UK/Netherlands with this suggestion tomorrow, but I think we have to find a way of getting this over to the States, as Heidi's defence of the system is simply that I should "let it learn my habits". It's clear from this thread that there are people who have been doing that for the last three years without success......
IMHO, what you describe is not a "way to command grid charging", rather it is a workaround that sort of gets you that result - at half power. At least your method presumably gives you a charging target based on the Reserve level you set. Good on you to have found that workaround. I would not have assumed that Self-Powered would do any grid charging.
