Forums

Powerwall 2 uses grid power when not needed.

Powerwall 2 uses grid power when not needed.

I wonder if anyone here has the same issue:
I have Tesla Powerwall-2, solar panels and inverter from Solar Edge since 7 August on the Big Island of Hawaii. The system is working great. However I noticed an odd behavior of the system in the following situation:
In the morning the battery is usually over 60% full. The panels produce more power then the house needs and the surplus power goes to charge the battery (our system does not export surplus power to the grid).
However at the same time the systems pulls 100-150 watt from the grid that in accordance to the Tesla app graphic goes to the house and the battery. This odd behavior continues until battery is charged 100%. At that moment the system stops pulling power from grid.
In the afternoon, when the panels start producing less power and the house starts using additional power from the battery, the system starts pulling 100-150 watt from the grid again, until dark when panels stop producing. At that moment the system stops pulling that power from grid and uses only the battery again. Our average consumption during the day is 500-1500 watt per hour and at night approx. 80 w/h.
Why would the system use grid at times when there is a lot more power produced by the panels than we consume?
This behavior pattern is repeating day after day. which I can see on the app graphic.
I called Tesla and the technical support agreed that this behavior is odd. They promised me to look at it and try to find the fix. However, the support person told me that because my Powerwall is working this issue is not a high priority. They said they will contact me when they will have an answer to this problem.

sashton | 16 September 2017

I had exactly the same symptoms, called Tesla support and they connected to the Gateway and corrected it. The support lady (from the Netherlands) then emailed me and said there was a configuration error which she corrected.
I wish I could directly offer you the solution but I didn't press her for the details.

mmani | 18 September 2017

Do they provide periodic OTA updates to powerwall software/firmware?
If so - we could/should request this config. fix to be in the default setting everywhere as a update-fix.

I hope.

sashton | 19 September 2017

Yes, there are updates applied OTA. Their schedule may differ by country but here in the UK mine was updated last week to 1.6.0 (it caused loads of problems but I have my fingers crossed they are sorted now).

zubinanary | 21 September 2017

The PowerwallOS gets updates automatically. I had mine installed on 9/13 and on that date it was running 1.5.1 which was the latest. On Tuesday it was automatically updated to 1.6.0.

The Tesla iOS app was also updated today, but that appears to be in support of the Model 3, and nothing to do with their Energy products.

peterswinnerton | 4 October 2017

I had the same issue: gateway pulling 100w or so power from the grid whenever the PV system had sufficient power to charge the pw2. However, I'm pleased to report that after speaking to technical support the engineer swiftly changed the configuration remotely, and the problem was rectified.

leotil | 20 November 2017

I guess you are not on Hawaii. I have this problem since September (s. my initial posting) and after several calls with Tesla USA and Tesla Hawaii representative, they cannot help. It looks like they have problem to understand the issue. They always tell me that PV system needs some little power from greed to run the system which I understand, but it cannot be over 100W per hour at the time when we get full sun and can produce over 5 KW energy that we hardly consume.
I wonder if anyone is here from Hawaii Island?

davbui | 7 July 2018

I have this issue. Home had low energy consumption and solar was powering battery, home and grid. But some grid power was used during this time ... ? I was going to call tech support but my Powerwall stopped working so I have to address that issue first.

sashton | 8 July 2018

There does appear to be an issue that the PW doesn't adjust to the changing PV generation and house loads as regularly when the time-based controls are selected. I have found that changing the setting back to self-powered usually cures the unexplained 100 - 400W grid draw when it occurs. Of course this only helps if you have this option and it is set.

Tesla-David | 8 July 2018

I am a relative newbie here, as we only had our two PW2 system turned on 15 days ago. We have been operating only in self-powered mode and have not used any energy from grid since turning on the PW2's. We are exporting ~62 percent of our solar energy generated back to Grid. We have Net Metering here, and they pay us for the excess energy generated. Our PW2's draw down from 100 percent to ~75 percent overnight, and the PW2's generally are charged back up to 100 percent by 10 a.m. We are not seeing any grid draw since we went operational, and we have been 100 percent self-powered over the past fifteen days. I have been blown away with how well the PW2's are working with our 13.2 kWh solar system.

spmeister | 13 July 2018

Just recently I started seeing something new -- when my EV is charging, the powerwalls no longer supply all of the energy. They tend to max out at around 3.8kW, when the house is using 11-12. The rest comes from the grid. I'm calling support today; this is costing me money!

sashton | 13 July 2018

@spmeister 3.8kW sounds suspiciously like the limit required in some locales. I would check the geo section of the gateway configuration to ensure it hasn't been inadvertently set. E.g. 3.68kW (16A 230V) is a limit in the UK for G83 restricted dwellings. Exceeding this requires prior permission from the power company here.

davbui | 27 July 2018

For the folks that had this issue fixed, can you provide detailed information on what Tesla did to fix this? I called Tesla tech support (in California) and they are claiming this is "normal behavior".

petedilloway | 3 May 2019

I’m in the UK. My PW2 is set to self powered but like others here, I get a constant small draw of 20 to 80watts from the grid when everything is just ticking over. My home draws a fairly constant 300 watts on tick over.
The Tesla app says I have used 0.8 KW in April. The true figure is 16KW more than twenty times that declared by the app.
Tesla say that the grid sensors don’t see less than 100watts yet their solar sensor is much more accurate. It’s only ten percent wrong!
My solar panel sensor and supply meter are accurate, why are Tesla’s so poor. Disappointing!

DermMD | 3 May 2019

To the OP
(our system does not export surplus power to the grid).

This may well be your explanation. A grid connection in a solar panel/Powerwall/Grid setup allows for constant balanced power supply. Without being a power engineer I would guess that Powerwall, in your setup, draws from the grid to achieve a constant power flow rate for charging. This is likely not possible with Solar panels alone as they produce at an unpredictable rate. Curious as to why you do not export to the grid? I suspect if you exported to the grid, even if not paid for the exported energy, you'd end up drawing less from the grid. If you were completely isolated from the grid the powerwall would have to charge from the solar panels at whatever rate, erratic as it may be, that the panels would allow. If it's possible I'd explore exporting to the grid even if not paid for it, if the power company will allow it in your area. After All you'd be exporting energy that would be wasted in your current setup. This is on the understanding that solar panels will produce electricity for as long as they're exposed to the sun whether you need the energy or not.

kalikikopa326 | 12 May 2019

Maybe I can explain since I'm in the same situation. The only programs offered by the OP's utility are you cannot export any energy to the grid, or you give the utility control over your system so it can be shut down in times if oversaturation.
In the former setup, his PV system pulls about .0.1kw throughout the day. Comes up to about 1 kwh a day, or about 30kwh a month. As with my system, when the powerwalls are fully charged my solar shuts off and my house pulls from the batteries. When the batteries drop a few percent, the solar turns back on, and the gateway pulls it's 0.1kw again. My batteries charge by about noon. It seems a waste to have my solar only work half the day, and yet I still have to purchase power from the utility.
One person replied that Tesla made a configuration change, and it solved this. My question is has anyone else had such luck?