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powerwall time based control working?

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I'm not a fully chartered accountant but afaik the rule to expense equipment through my company is for it to be used "wholly, exclusively and necessarily" for that purpose. Installing PW in your home seems really complicated to justify from this standpoint. Or you would have to work out a proper allocation method to expense a part of it (time spent working in your home office / sq.ft used / or energy consumption maybe)... not sure it's worth the risk of getting HMRC involved...
Yes, probably best to work out a proper allocation method instead and expense it as you suggest. My accountant made the same proposal.
I suppose it is a bit fiddly, but shouldn't be too bad to set something up based on energy consumption and time of day - 8-10 hours during the time we work.
 
@kuruma - Really interested by your original post before the thread descended... Were you ever able to resolve your issue with Powerwall not charging sufficiently during the off peak period?

We have 1xPW, but given what I know now I would never have had it installed, nor could I ever recommend it to others.

Frankly it’s ridiculous that you can’t even set a minimum charge level during the off peak period, particularly as Tesla’s AI doesn’t take into account anticipated solar generation. The level of user control is so far behind the curve when you consider the functionality other comparable systems offer e.g. givenergy.

The problem is exacerbated by the high Agile Export prices at the moment. I would like to ensure our PW is full at 5p/kWh to cover us overnight, and then export as much of our solar as possible at (currently) a minimum of 20p/kWh.

Very grateful for your experiences. Waking up at 0030 to set the reserve to 100% is not a viable option!
I am also in this situation?!? Have left it in Time Based Mode for a couple of weeks now and it still only charges to about 55%

Any further suggestions please?

10Kw of solar assisting when it can
 
I am also in this situation?!? Have left it in Time Based Mode for a couple of weeks now and it still only charges to about 55%

Any further suggestions please?

10Kw of solar assisting when it can
If you are able, move the reserve to say, 85% just after what ever time off peak cuts in. I did this for several nights and it seems to have got the message.
don’t forget to slide it back in the morning!
 
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so, now that we're back in the vicinity of needing to use time-based all the time now, we've got the opposite problem from when I first started the thread. We almost always find the PW is close to 100% in the morning. Never lower than 80% really. And this means that some days, we're giving to the grid because we've run out of things to use our excess solar on.

So, whatever the PW uses to calculate how much charge you need for the next day, it's usually inaccurate. It used to fall short. Now it's a surplus. I'm just thankful that I'm now on Intelligent Octopus so what I buy pretty much equals what I give to the grid.
 
this means that some days, we're giving to the grid because we've run out of things to use our excess solar on.

Surprised, and interested, that you are having that problem (as in "I'd like to have that problem too" !)

I hit 100% yesterday, and then the car charged to solve that. I've barely had any car charging at all in November

Last Sunday I had a small spike of Solar-beats-House battery charging ... and the previous one before that was 04-Nov

And I have most of PV on the ESE face, so starts producing about as early in the day as possible

Of course it all comes down to what the house consumption is relative to PV production, and mine is high (but I also have a lot pf panels)
 
it also helps if you have your car at home all day to suck up the excess at this time of year but that's not always possible. Yesterday was a good case in point. Wife did some washing, ran it through the dryer, put on some bread to bake and then gave up and let it flow out to the grid!
 
I have found a way to trick the system into a 100% charge overnight on ToU tariff.

I just set the offpeak period to 1p and doing this will ensure a 100% charge every night. I would rather do this over winter for peace of mind and not worry about using the washer or my air con on heat. Will revert back in spring and let the AI dictate how much off peak charge I need.
 
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Two days ago my PowerWall charged to 100% on Off Peak, as normal, but then started discharging 45 minutes before end of Off Peak (happens that I noticed, and I set reserve to 100% which fixed that). No idea what would have caused that, but it increases my wish to have an APP with Scheduler to control these things, so that "out of sight, out of mind" doesn't do something that is not best for my personal scenario.
 
My Powerwall and gateway was installed last Friday and I’ve put in on time based control. I’m currently on Octopus Go at 7.5p off peak and 35p on peak.

When it was installed on Friday, it had 20% battery but we had very little solar that day so I hit reserve very soon and started to take peak power from the grid on Friday afternoon.

The Powerwall filled up to 100% overnight (Saturday morning) and we produced only a small amount of solar again on Saturday (4kwh) but the battery lasted the day, with no peak power taken from the grid.

The Powerwall charged back up to 100% overnight (Sunday morning) and Sunday was similar to Saturday in that the battery lasted the day (5kwh from solar and no peak power from the grid) and had about 25% left when I went to bed Sunday night.

On Monday morning, the Powerwall only charged to 58% overnight. Not sure why or what prompted this. There wasn’t a lot of solar on Monday (4.5kwh) and the battery managed to last the day (no peak power again 😁) but was only just above reserve when I went to bed ( I have reserve set at 15%). The decision to charge to 58% looked a sound one although I did think it had undercooked it when I first checked the app on Monday morning.

This morning the Powerwall charged back to 100% which I was not expecting it to do as solar generation looked more promising for today. As 10am, I have already generated 4kw from solar, the battery is full and am exporting to the grid which I was hoping not to do. I was only expecting the off peak charge to top up to around 50%, not 100%.

The cost differential is nothing really, 7.5p paid off peak use vs 4.1p credit to export to the grid but it would be nice to understand why it does what it does.

The only difference on Sunday night/Monday morning when the battery charged to 58% was that the car wasn’t on charge that night. It was on charge all the other nights when the battery also charged to 100%. I don’t know why this would make a difference and suspect it is just the gateway learning my usage habits.

My house is on single phase, 100 amp fuse and pulls 12.9kwh off peak – 7.5kwh for the car, 5kwh for the battery and a few hundred watts for the house. We use around 10,000kwh per year (4.5 for the car and 5.5 for the house).

Anyway, enjoying my purchase so far, if not a little too keen to be constantly checking on the app!
 
My Powerwall and gateway was installed last Friday and I’ve put in on time based control. I’m currently on Octopus Go at 7.5p off peak and 35p on peak.

When it was installed on Friday, it had 20% battery but we had very little solar that day so I hit reserve very soon and started to take peak power from the grid on Friday afternoon.

The Powerwall filled up to 100% overnight (Saturday morning) and we produced only a small amount of solar again on Saturday (4kwh) but the battery lasted the day, with no peak power taken from the grid.

The Powerwall charged back up to 100% overnight (Sunday morning) and Sunday was similar to Saturday in that the battery lasted the day (5kwh from solar and no peak power from the grid) and had about 25% left when I went to bed Sunday night.

On Monday morning, the Powerwall only charged to 58% overnight. Not sure why or what prompted this. There wasn’t a lot of solar on Monday (4.5kwh) and the battery managed to last the day (no peak power again 😁) but was only just above reserve when I went to bed ( I have reserve set at 15%). The decision to charge to 58% looked a sound one although I did think it had undercooked it when I first checked the app on Monday morning.

This morning the Powerwall charged back to 100% which I was not expecting it to do as solar generation looked more promising for today. As 10am, I have already generated 4kw from solar, the battery is full and am exporting to the grid which I was hoping not to do. I was only expecting the off peak charge to top up to around 50%, not 100%.

The cost differential is nothing really, 7.5p paid off peak use vs 4.1p credit to export to the grid but it would be nice to understand why it does what it does.

The only difference on Sunday night/Monday morning when the battery charged to 58% was that the car wasn’t on charge that night. It was on charge all the other nights when the battery also charged to 100%. I don’t know why this would make a difference and suspect it is just the gateway learning my usage habits.

My house is on single phase, 100 amp fuse and pulls 12.9kwh off peak – 7.5kwh for the car, 5kwh for the battery and a few hundred watts for the house. We use around 10,000kwh per year (4.5 for the car and 5.5 for the house).

Anyway, enjoying my purchase so far, if not a little too keen to be constantly checking on the app!
I get times when I wonder what it’s playing at but overall it’s not bad at guessing. If you still have surplus consider a solar diverter to power your immersion heater if you have one.
Interestingly, today is a good case in point. 70% at bedtime last night but only topped up a bit and was 73% when I got up. Weather forecast was dire; rain/sleet/snow.
Weather is actually nothing like that. Now at 100% and car getting 4kWh of spare solar!