Folks,
Update — The detailed  instructions, etc, are now available from Venstar Thermostat Monitor.
I have just created a new plugin that will allow Venstar Insteon Thermostat users to monitor their daily usage of AC, Heating, and Fan usage… Â This is a basic plugin designed to extend Indigo…
When installed, the plugin is most noticeable in the Log file…
Received INSTEON Â “Furnace Link” off (button 2)
Thermostat     Insteon Thermostat Event being processed
Thermostat     Thermostat requesting Heating – Off
Thermostat     Furnace Heat Ran for 14 Minutes
Thermostat     Thermostat Event Processing Done
Please note, you will need to make a new timed action that runs thermo_reset.scpt whenever you want to reset the counters… Â I would suggest midnight, so that you are capturing the 24 hrs period… Â The script will append to a csv file in your documents folder that contains the value that are in the AC, Furnace and Fan variables, and then reset the variables to 0.