Smart Solar Charging

[markboris]

I think Lee made a great diagram of your system. I bet that's exactly how it is. If that is the case, it looks like those 200A CT's you had connected originally were ok. It is not a complicated setup so whatever the issues is, has to be simple. I don't understand what we are overlooking. I am also very surprised at the support you got from Emporia. Might want to try again as the few times I called with other questions, they spend time with me until they were solved. None of it had to do with the charger though. I wanted to monitor the Powerwalls and as of right now they don't have a CT that goes both ways but they are working on one that does specifically for batteries and soon we will be able to monitor those too.

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[ridgebackpilot]

In thinking about this, it's important not to make it more complicated than it is. That's easier for me, since I can use the Emporia Vue Utility Connect and hence avoid the need to install any sensors. As you may know, the Utility Connect wirelessly receives information from my Smart Meter and monitors only one thing: How much electrical energy is being taken from or sent back to the grid.

Fortunately, that's exactly the information the Emporia app needs to power the Emporia Level 2 charger by excess solar energy. When the Utility Connect senses significant electricity being sent back to the grid, the app activates the Emporia EV charger and varies the rate of charge according to the amount of excess solar energy available.

The point of this story is that to control your Emporia charger properly, the Emporia app only needs to know whether you're sending solar power back to the grid or not. That means all you really need to monitor is the current flowing to or from your main utility service. You could conceivably hook up your Emporia Vue to your main panel and avoid the Tesla Gateway entirely.

 

[markboris]

In thinking about this, it's important not to make it more complicated than it is. That's easier for me, since I can use the Emporia Vue Utility Connect and hence avoid installing any sensors. As you probably know, the Utility Connect wirelessly monitors only one thing: How much electrical energy is being taken from or sent back to the grid.

Fortunately, that's exactly the information the Emporia app needs to power the Emporia Level 2 charger by excess solar. When the Utility Connect senses significant energy being sent back to the grid, the app activates the Emporia charger and varies the rate of charge according to the amount of excess solar energy available.

The point of this story is that to control your Emporia charger properly, the Emporia app only needs to know whether you're sending solar power back to the grid or not. That means all you really need to monitor is the current flowing to or from your main utility service. You could conceivably hook up your Emporia Vue to your main panel and avoid the Tesla Gateway entirely.

Michael, that is exactly what I tried/meant to say in my earlier post. It is very simple and that is all the Vue app needs to know. My two 200A sensors are right at the main grid feed coming in and that is all that the EV charger needs to charge on excess solar. Thanks for explaining it in more detail.

 

[skiingj]

Thanks Mark / Michael. I am still waiting for a call back from Emporia. It is charging a little better and not draining my Powerwalls as much. What is still a problem, it starts a EV charge when it hasn't pushed any energy to the grid. The app appears to be seeing the energy level just fine. I have reset and rebooted and such to no avail. Hopefully they will call tomorrow.

 

[markboris]

John, if Emporia does not call you first thing this morning, call them again. I am about ready to stop by next time I go to Sac airport and see if I can help you out with this.

 

[skiingj]

After a couple more days of phone tag I was able to speak with them today. They know there is an issue with the Vue/Charger pulling from Powerwall’s. They are working on an update to fix the issue but do not have an ETA.

They mentioned using Time-Based Control. I am trying that again so we will see.

Here are some screenshots. You can see the progression of the grid being fed power, Vue seeing the overage, charger activating, and the ramp up of the EV charger well past what I was feeding the grid.

 

[markboris]

After a couple more days of phone tag I was able to speak with them today. They know there is an issue with the Vue/Charger pulling from Powerwall’s. They are working on an update to fix the issue but do not have an ETA.

They mentioned using Time-Based Control. I am trying that again so we will see.

Here are some screenshots. You can see the progression of the grid being fed power, Vue seeing the overage, charger activating, and the ramp up of the EV charger well past what I was feeding the grid.

However, I don't have this problem with my PowerWalls when they are set to either Time-Based or Self-Powered. Maybe this issue only affects some of their EV chargers? I have two chargers and neither one have this issue. I assume they said your sensors were connected properly and your app set up correctly?

John, on your Emporia app, charging screen, why doesn't it say "Controlled by Excess Solar"? Like this:

 

[ridgebackpilot]

Thanks Mark / Michael. I am still waiting for a call back from Emporia. It is charging a little better and not draining my Powerwalls as much. What is still a problem, it starts a EV charge when it hasn't pushed any energy to the grid. The app appears to be seeing the energy level just fine. I have reset and rebooted and such to no avail. Hopefully they will call tomorrow.

John & Mark: Based on my own experience and system, I'm convinced the settings in the Tesla app are one of the keys to resolving the situation we're experiencing with the Emporia charger.

When I set my Tesla app on "Self-Powered", the Tesla Gateway pushes Powerwall energy to the Emporia charger. That means the charger maintains its maximum rate of charge, in my case 40 amps. The Powerwalls make up for any shortfall in excess solar production. That scenario can drain the Powerwalls pretty quickly, as you've pointed out.

However, when I set the Tesla app on "Time-Based Control", it works far better. The Tesla Gateway knows not to draw any power from the grid during Peak or Part-Peak hours. It also doesn't rely on energy from the Powerwalls to power the charger. That means the Emporia app is free to sense excess solar energy being dumped to the grid, and begin charging accordingly.

But here's the rub: I have to switch between "Self-Powered" and "Time-Based Control" every morning! That's because if I leave the Tesla Gateway set to "Time-Based Control" overnight, it will make use of off-peak grid energy when I'd rather be using energy from the Powerwalls. But if I leave it set to "Self-Powered" during the day, the Emporia charger won't be able to restrict its use to excess solar energy alone.

What we really need to figure out is the optimal way for three different but related apps to interact: the Tesla app, the Emporia app, and the FordPass app. How have you got yours set to work well together? The problem is they each are capable of doing similar things. For example, I set the FordPass app to "charge when plugged in" because otherwise it wouldn't allow charging during peak grid hours, even if there is excess solar energy available.

Thanks for your thought-partnership here; I'm learning a lot from you guys!

 

[markboris]

Michael, I have mine set to Self-Powered and the Emporia charger only charges on excess solar. It makes no difference how I have the Powerwalls set, the charger only charges on excess solar.

Maybe this whole issue has to do with the way the Powerwalls and Gateway are setup. I also have the older Gateway 1 while you guys might have the Gateway 2. I have a separate backup panel that the Powerwalls power in case of a grid outage however when I set it to self-powered, the Powerwalls power the entire house, not just the backup panel. My solar inverter and Powerwall breakers are in he backup panel while the EV chargers are in the Main panel.

 

[ridgebackpilot]

Michael, I have mine set to Self-Powered and the Emporia charger only charges on excess solar. It makes no difference how I have the Powerwalls set, the charger only charges on excess solar.

Maybe this whole issue has to do with the way the Powerwalls and Gateway are setup. I also have the older Gateway 1 while you guys might have the Gateway 2. I have a separate backup panel that the Powerwalls power in case of a grid outage however when I set it to self-powered, the Powerwalls power the entire house, not just the backup panel. My solar inverter and Powerwall breakers are in he backup panel while the EV chargers are in the Main panel.

Mark: I'll bet you're on to something here.

I've got the Tesla Gateway 2 and don't have a separate "critical loads" panel.

Both of my solar arrays and the Powerwalls are connected via the Tesla Gateway to my main panel, which powers the entire house. The older array has a single SolarEdge inverter, but the newer panels have Sun Power micro-inverters. Still, all are connected via the Tesla Gateway to back up the entire house.

 

[markboris]

Mark: I'll bet you're on to something here.

I've got the Tesla Gateway 2 and don't have a separate "critical loads" panel.

Both of my solar arrays and the Powerwalls are connected via the Tesla Gateway to my main panel, which powers the entire house. The older array has a single SolarEdge inverter, but the newer panels have Sun Power micro-inverters. Still, all are connected via the Tesla Gateway to back up the entire house.

Yes, that is probably it. My backup panel is between the gateway and main panel. The SolarEdge inverter 60A breaker is in the backup panel along with the 4 30A Powerwall breakers. The main panel has the 2 60A EV charger breakers and the 100A backup panel breaker. The Emporia Vue 200A sensors are connected to the mains coming into the main panel

 

[skiingj]

However, I don't have this problem with my PowerWalls when they are set to either Time-Based or Self-Powered. Maybe this issue only affects some of their EV chargers? I have two chargers and neither one have this issue. I assume they said your sensors were connected properly and your app set up correctly?

John, on your Emporia app, charging screen, why doesn't it say "Controlled by Excess Solar"? Like this:

Yes everything connected properly. I sent them the screenshots and they confirm the Vue is seeing the power going back to the grid and it does match up with what Tesla is displaying.

I sometimes see controlled by excess solar but not all the time. This morning it starts charging immediately even though the Powerwall is not fully charged and it has yet to sell back any power.

Frustrating. Hopefully the fix is not long off. They did not have a ETA just said it is taking longer than expected.

 

[skiingj]

Time-Based controls don't appear to work for me. In the Tesla settings there is really nothing to set. I name my city utility company and put in price per kWh. There are no seasons and no difference in day/night pricing.

 

[ridgebackpilot]

My Emporia app looks the same as Mark's.

 

[ridgebackpilot]

Time-Based controls don't appear to work for me. In the Tesla settings there is really nothing to set. I name my city utility company and put in price per kWh. There are no seasons and no difference in day/night pricing.

John: Are you certain about this? First, if you look under "Settings" on the Tesla app, you'll see "Powerwall" where you can set it to "Self-Powered" or "Time-Based Control".

Also, if you have PGE or SMUD, you will almost certainly have peak, near-peak, and off-peak electricity rates. There's a big difference among the rates and you'll save a lot by setting your apps to make sure you never draw from the grid during peak or near-peak hours!

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