EMON utility electrical power measurements

Using the ESP32 with the EMON library is presenting several challenges:

1. Power measurements, compared with measurements using electronic test equipment, seem to vary slightly.  Not sure if this is due to PF correction, voltage or current measurement resolution, duration of the measurement (currently using 30 zero crossings), or . . .

2. The use of split-phase power in the U.S. This requires two measurement channels and the independent quantification of voltage, current, and PF. Not 100% sure I've set this up properly.

3. The EMON library is not clearly documented.  At least I cannot find all the info I need to make solid, repeatable, accurate measurements.  Again, I'm a bit of a novice at this Arduino stuff so it could be my shortcoming.

4. The input port impedance of the ESP32 is not clearly defined.

5. Because the utility power is AC (not DC) the measurements require a reference point other than ground.  I believe I've solved this by providing a stable 1.65V reference for the voltage and current measurements, but I'm not 100% sure I've done this appropriately.  Glad to provide schematics if you're interested in this topic.

5. Electrical power, like many other things, is getting more expensive.  The ability to monitor and control power (especially if you have renewable energy generation) is becoming more desirable, especially if you want to optimize your local power consumption/generation without going through the complicated, confusing, frustrating, expensive permit process.

I hope you find this topic interesting.  If you decide to pursue it, I'll help in any way I can.

Thank you for your excellent work!