Powerwall operation problems

[RedMod3]

Had an interesting Powerwall / Gateway problem today.

Yesterday was very cloudy, and although I am on time based control, the PW did not charge up fully the previous night, so I was on full priced power from 4pm.

So, last night, just after the cheap rate came on, I set the reserve % at 50%, to guarantee a full charge for today.

However, I woke up late and the 50% charge level had already been reached, and the PW was charging at 5kW!

I tried adjusting the reserve % but it had no effect even after waiting a bit. Then tried powering off the PW, and that stopped the 5kW draw, but as soon as I turned the PW back on again, the 5kW draw returned with a vengeance.

Next I tried turning off the Gateway breaker, and back on after a short while, but the 5kW draw returned.

The solution was to go off-grid for 10 mins (this was the first time I had ever tried this), and that fixed the problem, and I am now back to normal.

Any comments?

 

[Dilly]

When trying to force a time based charge, I usually find switching to self powered and back clears the AI memory.
if I happen to be awake at 12.30 am, I rack up the reserve to about 75% and that sorts it!

 

[RedMod3]

When trying to force a time based charge, I usually find switching to self powered and back clears the AI memory.
if I happen to be awake at 12.30 am, I rack up the reserve to about 75% and that sorts it!

Thanks, I'll remember that one.

Summer has interesting challenges. With only one PW (one more due soon), if I charge the PW up too much at night, and it is sunny, I generate surplus power and too much to heat water and charge cars. But, if I don't charge enough at night, I end up paying peak rates for too long.

It is a shame manual % control in Time Based Control is not an option too.

 

[Dilly]

it’s the same ’AI rules’ philosophy that plagues in car charge schedules! What’s wrong with simple?
two Powerwalls makes it easier but if the cars haven’t moved and we haven’t haven’t used much hot water, we still end up dumping it in the grid!
The upside is I’ve only used 69p worth of grid power this month and I’ve I’ve been on self powered since mid March.
I can’t get to zero without going off grid but I’m not that tight!

 

[scdoubleu]

If you're up for some coding, there are projects on GitHub which can help automate setting the backup reserve percentage using Tesla's cloud API. This is just one example.

 

[WannabeOwner]

Summer has interesting challenges. With only one PW (one more due soon), if I charge the PW up too much at night, and it is sunny, I generate surplus power and too much to heat water and charge cars. But, if I don't charge enough at night, I end up paying peak rates for too long.

It is a shame manual % control in Time Based Control is not an option too.

I'm in the same boat ... on E7 I'm needing to stay up to midnight to then set reserve to 100% (or something lower - based on my assessment of tomorrow's cloud cover), and then during the day juggling car charging / battery filling from PV to try to get 100% PowerWall at just the moment the sun goes in to maximise battery discharge in the evening

Whilst I have a Zappi which will divert to car when over-producing PV I'm not comfortable with the rate that the PV charges that batteries (I have read that the from-grid rate is chosen to be idea for battery health, my PV charges the battery in less than half that time ...

... so I'm thinking that some tinkering with API is needed, my aim being to charge car (or some other "divert") whilst the batteries are charging to reduce the charge rate

This is just one example.

Thanks, not seen that one I've done a fair bit of Googling ... turned up a number of "projects", disappointed there isn't a product (like TeslaFi) that could be used for this. I have the programming ability, but not the time ... and the biggest snag I foresee is when something in the API / Security changes as anything I built DIY would then need urgent tinkering to continue to operate

 

[PITA]

Had an interesting Powerwall / Gateway problem today.

Yesterday was very cloudy, and although I am on time based control, the PW did not charge up fully the previous night, so I was on full priced power from 4pm.

So, last night, just after the cheap rate came on, I set the reserve % at 50%, to guarantee a full charge for today.

However, I woke up late and the 50% charge level had already been reached, and the PW was charging at 5kW!

I tried adjusting the reserve % but it had no effect even after waiting a bit. Then tried powering off the PW, and that stopped the 5kW draw, but as soon as I turned the PW back on again, the 5kW draw returned with a vengeance.

Next I tried turning off the Gateway breaker, and back on after a short while, but the 5kW draw returned.

The solution was to go off-grid for 10 mins (this was the first time I had ever tried this), and that fixed the problem, and I am now back to normal.

Any comments?

How I manage this with two Powerwalls, is to let Time-Based-Control charge the Powerwalls up overnight, so I've always got power for the home.

Then...

- If it's a Sunny Day, better than expected, I charge the cars from the Powerwalls to make space for more Solar during the day.

- If it's a cloudy day, I'll leave the Powerwalls just for home use. If I suddenly need a huge car charge, I'll stick it on the 3 Phase charger which bypasses the Powerwalls for 'emergency use' at 30p Peak Rate.

- If it looks to be a run of Cloudy days (or Winter), I leave the Powerwalls in Time-Based-Control and charge the car at off-peak rates (7.5p)

- If it looks to be a run of Sunshine for a few days, I put the Powerwalls into Self-Powered mode and just take excess into the Cars, as and when it's needed.

Seems to work well, and I only have about 2% export levels.

 

[RedMod3]

How I manage this with two Powerwalls, is to let Time-Based-Control charge the Powerwalls up overnight, so I've always got power for the home.

Then...

- If it's a Sunny Day, better than expected, I charge the cars from the Powerwalls to make space for more Solar during the day.

- If it's a cloudy day, I'll leave the Powerwalls just for home use. If I suddenly need a huge car charge, I'll stick it on the 3 Phase charger which bypasses the Powerwalls for 'emergency use' at 30p Peak Rate.

- If it looks to be a run of Cloudy days (or Winter), I leave the Powerwalls in Time-Based-Control and charge the car at off-peak rates (7.5p)

- If it looks to be a run of Sunshine for a few days, I put the Powerwalls into Self-Powered mode and just take excess into the Cars, as and when it's needed.

Seems to work well, and I only have about 2% export levels.

Thanks PITA, but my real issue was my single PW was sucking in 5kW of grid power at peak rate when the reserve percentage on the PW was much less than the state on charge of the PW. I was angry that I was paying 90p/hour to unnecessarily charge the PW, when I didn't need the charge. Something was wrong with the PW charging.

Even on a very sunny day, I'm happy to charge the PW to 75%, and use surplus energy to top up my M3P with the Tesla charger and the Smart car with the Granny, and if I still have surplus power the immersion comes on.

I need to force at least a 75% charge this evening as we are going on full cost power around 7pm after only 14kWh were generated today.

 

[RedMod3]

I'm in the same boat ... on E7 I'm needing to stay up to midnight to then set reserve to 100% (or something lower - based on my assessment of tomorrow's cloud cover), and then during the day juggling car charging / battery filling from PV to try to get 100% PowerWall at just the moment the sun goes in to maximise battery discharge in the evening

In my feedback to Tesla, I asked for manual control over PW charging from the grid; doubt we will get it though.

 

[ElectricJoules]

Anybody else suffering from false power outages, where the Powerwall goes into backup mode for a few minutes and then recovers? It started about 10 days ago, after over a month of happy operation following the installation. Yesterday I had over 50 event, and today at 11:40 I've already had 20 events. I've contact the installer and was told they have just started to have similar problems and are looking into it. Both me and the installer are in West Sussex, I wonder if others in the area are having problems? When it happens the gateway breakers can be heard switching. I assume the system thinks the incoming mains has gone bad (either voltage or frequency).

 

[Dilly]

Anybody else suffering from false power outages, where the Powerwall goes into backup mode for a few minutes and then recovers? It started about 10 days ago, after over a month of happy operation following the installation. Yesterday I had over 50 event, and today at 11:40 I've already had 20 events. I've contact the installer and was told they have just started to have similar problems and are looking into it. Both me and the installer are in West Sussex, I wonder if others in the area are having problems? When it happens the gateway breakers can be heard switching. I assume the system thinks the incoming mains has gone bad (either voltage or frequency).

Nothing like that here in Norfolk
I had 3 events last Sunday morning and a couple back in April. Each lasted just a few seconds

 

[RedMod3]

Anybody else suffering from false power outages, where the Powerwall goes into backup mode for a few minutes and then recovers? It started about 10 days ago, after over a month of happy operation following the installation. Yesterday I had over 50 event, and today at 11:40 I've already had 20 events. I've contact the installer and was told they have just started to have similar problems and are looking into it. Both me and the installer are in West Sussex, I wonder if others in the area are having problems? When it happens the gateway breakers can be heard switching. I assume the system thinks the incoming mains has gone bad (either voltage or frequency).

None is SE Hampshire. Have you asked neighbours if they have seen any light flickering?

 

[ElectricJoules]

I've had a reply from our installer -

We have followed up with Tesla regarding the issues that we have both experienced and have received the following, hopefully UK Power Networks will get the grid stabilised again soon.

Tesla support provided this -

So it appears the Powerwall was doing what it is supposed to. It would be interesting to know the limits in the Powerwall software that will trigger the disconnect.

 

[RedMod3]

I've had a reply from our installer -

We have followed up with Tesla regarding the issues that we have both experienced and have received the following, hopefully UK Power Networks will get the grid stabilised again soon.

Tesla support provided this -

View attachment 802519

So it appears the Powerwall was doing what it is supposed to. It would be interesting to know the limits in the Powerwall software that will trigger the disconnect.

Impressive support from the Tesla network. A good reason to choose a Powerwall and not alternative brands.

 

[PITA]

I've had a reply from our installer -

We have followed up with Tesla regarding the issues that we have both experienced and have received the following, hopefully UK Power Networks will get the grid stabilised again soon.

Tesla support provided this -

View attachment 802519

So it appears the Powerwall was doing what it is supposed to. It would be interesting to know the limits in the Powerwall software that will trigger the disconnect.

It's the Grid having a dress rehearsal for this coming Winter.

Powerwalls will be busy, I think...

(No Grid stability issues here in West Midlands)

 

[Gatsojon]

All systems and uses are different but for me, I find the Tesla tariff to be good value all year really. Yes you loose control of your Powerwall but that worries me less than some. We don’t really have the sort of control others do anyway. The rates have just increased to 11p in and out at all times. Used to be 8p.

 

[Lx2m3]

All systems and uses are different but for me, I find the Tesla tariff to be good value all year really. Yes you loose control of your Powerwall but that worries me less than some. We don’t really have the sort of control others do anyway. The rates have just increased to 11p in and out at all times. Used to be 8p.

I should be having my PV and PW + Gateway installed in June and am considering going onto the Tesla tariff, sounds like a lot less hassle than the alternative.
Do you get all data flow information on this tariff?

 

[Gatsojon]

I should be having my PV and PW + Gateway installed in June and am considering going onto the Tesla tariff, sounds like a lot less hassle than the alternative.
Do you get all data flow information on this tariff?

I don’t know what you mean by data flow, sorry. You can get your use by half hour slots if you want and I think download that. If you’re talking about API things, then that’s beyond my interest or ability.

 

[RedMod3]

I should be having my PV and PW + Gateway installed in June and am considering going onto the Tesla tariff, sounds like a lot less hassle than the alternative.
Do you get all data flow information on this tariff?

Why Tesla tariff, if you're on Octopus GO and with a PW, you'll never pay more than 7.5p per kWh, and your average will be well under that with solar.

 

[Gatsojon]

Why Tesla tariff, if you're on Octopus GO and with a PW, you'll never pay more than 7.5p per kWh, and your average will be well under that with solar.

Like I said, every system and use is different so you have to make your own choice. With a relatively low mileage requirement but high daytime use, Tesla Tariff works out cheaper and less hassle for me.