Update: After factory resetting the EAGLE and calling PG&E to try to pair it again, they were able to pair the EAGLE to the SmartMeter this time. So now I'll begin exploring the data it's gathering from the meter and what can be done with it.
rhanson wrote:So if I understand correctly, this RFA device is a Zigbee-to-Ethernet bridge of sorts? Could we just use a USB Zigbee device to talk to the meter instead? Is there some advantage (other than having multiple devices be able to talk to this thing) for going the ethernet route?
Correct. In a very similar way to how the Philips Hue hub is a ZigBee-to-Ethernet bridge for the Hue light bulbs, the RFA-Z109 EAGLE bridges the SmartMeter to Ethernet. It is likely possible to pair a USB ZigBee interface to the SmartMeter. The SmartMeters (at least the ones PG&E uses) require that they be the coordinator of the ZigBee network, which may or may not pose an issue for centrally managing the connection from home automation software. Currently, my understanding of the ZigBee standard is very limited, so I don't know what challenges would be associated with doing that. From what I've read so far, the ZigBee standard, similar to Bluetooth, incorporates numerous application profiles. SmartMeters support the "Smart Energy Profile" (SEP), either version 1.0 or 1.1, so whatever device (USB or otherwise) that connects to the meter needs to support the SEP profile, either through software or hardware. I don't have the time to learn all the ins-and-outs of ZigBee communication and application profile standards, then develop software to implement it. That's a much bigger project than a simple XML data exchange between the EAGLE and Indigo plugin over an existing network layer. I do know that the SmartMeters support coordinating more than just one ZigBee device, so you could connect the EAGLE as well as a display device and USB device all to the same meter. So, is there an advantage to using the EAGLE over some USB stick? Yes. Simplicity, both in pairing and in data gathering. The EAGLE, out of the box, also provides a basic embedded web interface that shows current readings along with energy usage and demand history for up to a year. It can be configured to forward all data to a 3rd party "cloud" energy tracking web site, and Rainforest Automation includes a free iOS and Android app to view the data in real-time while on the same local network as the EAGLE. We'd get none of that with a basic USB ZigBee device.
rhanson wrote:I have solar and drive an EV, so for me it would be a few things:
- monitor solar production and be able to know when I'm "ahead of the game". This will likely involve talking to the solar monitor device as well. But one step at a time.
- be able to tell if my car stops charging, or didn't charge for some reason (like I forgot to plug it in!)
- keep an eye on the A/C
I don't know how the EAGLE handles negative demand (energy going back to the energy company form your solar system), but I assume it just reads the data from the meter and doesn't care one way or the other. Maybe you could let us know what it shows for that when you get it all set up at your location.
Being able to tell if your car stops charging might be possible, but you'd have to do the energy "profiling" in your head by looking at the historical data viewable from the EAGLE web interface or a 3rd party "cloud" service's analysis. It might also be possible in the future, by correlating the times when an Indigo device turns on or off with trends in the historical usage data. This would be an advanced feature, though, as it would require the incorporation of database logging and statistical analysis of historical data. I'm not sure I'm up that (yet anyway). Something that would probably be much less difficult to implement would be something like a 5-minute "delta" value which could be used to track change in usage over a fixed short period. If this value suddenly grew large, you'd know something big was just turned on.
Keeping an eye on the A/C usage would be a lot easier as it uses a lot of energy. A spike in demand like that is hard to miss and you could set up electrical demand-based triggers in Indigo to keep track of that.
My thoughts for a first release plugin are to provide very basic Indigo integration, making the real-time data available to Indigo for whatever demand and usage notifications one may wish to set up. Subsequent versions might include more calculated data (such as average demand increase/decrease states) to help identify high usage electrical equipment and trends better. Of course, all of this is contingent on how much free time I have outside of my day job and family life.
But at minimum, I expect to get the above first release features into a plugin. And, like my other plugins, I don't currently plan on charging anything for it.