I recently had Tesla solar panels and PowerWalls installed at my house. They are great. I live in the greater Chicago area and our utility, ComEd, allows the combination of Time of Day pricing (which I've been on for 2+ years ever since I bought my Model X) even when a solar power system is installed. Time of Day pricing generally has pricing higher during the day and lower at night, with the occasional exception.
So when I generate excess electricity during the day and push it out to the grid, ComEd typically pays me more per kWh for what I push out to them than I pay them when I pull electricity from grid at night after my PowerWalls have been drawn out. I can see on a public web site ComEd provides Live Prices | ComEd's Hourly Pricing Program how much I'm paying (or being paid) per kWh with the rates changing every 5 minutes. I can also use the Tesla app to see how much I'm pulling or pushing from/to the grid at any given time. Great.
On occasion, and so far in the past two years I've only seen this happen at night, rates go negative. So ComEd actually pays me to take electricity off their hands. In fact, this has happened 3-4 nights in the past 10 days. However, it happens when I'm sleeping and I find out only after the fact when I see it on the ComEd web page and so I can't do anything to take advantage of it since by then rates have gone back above zero.
I have my Tesla set to charge at 1:00 AM. However, I don't always plug my car in and I also don't drive it every day, so even if it's plugged in and ready to charge there may not be any charging needed. I have my PowerWalls set to discharge until they are 30% of capacity and then the system pulls from the grid. So when the rates go negative 1) I might still be discharging the PowerWalls and not pulling from the grid 2) the Tesla may not be plugged in 3) if it is plugged in there may not be much charge needed.
So it occurred to me that if I had a app running on my phone (iOS FWIW) that did the following:
- Monitor the ComEd app for the moment rates go negative and when they do:
- Change the setting on the PowerWalls (via the Tesla app?) to not discharge (by changing the setting to 100% capacity), meaning the batteries don't discharge and the house immediately starts to pull electricity from the grid.
- Change the setting on the car to start charging. This presumes the car is plugged in but I've set it not to charge. That's easy, I can start always plugging it in.
- When rates go positive, reset the car and the PowerWalls back to their original settings.
- The idea is that when rates go negative I'm doing whatever I can to pull electricity from the grid and getting paid for it.
I'm in the technology (software) business and used to do a lot of programming so I know this should be able to be done. A few issues, 1) I'm not an iOS or Android programmer and don't want to become one, 2) I don't know if the settings on the Tesla app can be accessed and if it's legal to do so, 3) Pulling and extracting the information from the ComEd web site is easy.
I'm willing to pay someone to write such an app assuming it passes the legal and technical tests. After all, while it may take some time, the app will pay for itself. And I'm sure there are others in my same position in the Chicago area willing to pay for the app and help me recoup the expense to create it.
If you are interested or know sometime who would be, reply to this thread or contact me at davidferri at iCloud.
So when I generate excess electricity during the day and push it out to the grid, ComEd typically pays me more per kWh for what I push out to them than I pay them when I pull electricity from grid at night after my PowerWalls have been drawn out. I can see on a public web site ComEd provides Live Prices | ComEd's Hourly Pricing Program how much I'm paying (or being paid) per kWh with the rates changing every 5 minutes. I can also use the Tesla app to see how much I'm pulling or pushing from/to the grid at any given time. Great.
On occasion, and so far in the past two years I've only seen this happen at night, rates go negative. So ComEd actually pays me to take electricity off their hands. In fact, this has happened 3-4 nights in the past 10 days. However, it happens when I'm sleeping and I find out only after the fact when I see it on the ComEd web page and so I can't do anything to take advantage of it since by then rates have gone back above zero.
I have my Tesla set to charge at 1:00 AM. However, I don't always plug my car in and I also don't drive it every day, so even if it's plugged in and ready to charge there may not be any charging needed. I have my PowerWalls set to discharge until they are 30% of capacity and then the system pulls from the grid. So when the rates go negative 1) I might still be discharging the PowerWalls and not pulling from the grid 2) the Tesla may not be plugged in 3) if it is plugged in there may not be much charge needed.
So it occurred to me that if I had a app running on my phone (iOS FWIW) that did the following:
- Monitor the ComEd app for the moment rates go negative and when they do:
- Change the setting on the PowerWalls (via the Tesla app?) to not discharge (by changing the setting to 100% capacity), meaning the batteries don't discharge and the house immediately starts to pull electricity from the grid.
- Change the setting on the car to start charging. This presumes the car is plugged in but I've set it not to charge. That's easy, I can start always plugging it in.
- When rates go positive, reset the car and the PowerWalls back to their original settings.
- The idea is that when rates go negative I'm doing whatever I can to pull electricity from the grid and getting paid for it.
I'm in the technology (software) business and used to do a lot of programming so I know this should be able to be done. A few issues, 1) I'm not an iOS or Android programmer and don't want to become one, 2) I don't know if the settings on the Tesla app can be accessed and if it's legal to do so, 3) Pulling and extracting the information from the ComEd web site is easy.
I'm willing to pay someone to write such an app assuming it passes the legal and technical tests. After all, while it may take some time, the app will pay for itself. And I'm sure there are others in my same position in the Chicago area willing to pay for the app and help me recoup the expense to create it.
If you are interested or know sometime who would be, reply to this thread or contact me at davidferri at iCloud.
