I've been successful in collecting data from my gas meter via rtlamr & logging to emoncms. The data is in lifetime cubic feet, so I have the processing set up to convert this to a time interval difference, log to a feed, accumulate, and then track daily total.
I'd now like to add in two more components:
(1) cubic feet to therms - on each month's gas bill, my utility company shows the value (currently 1.024 BTU/CCF), which can change from month to month, although usually not by much. I won't know this until after the billing cycle, at which point I suppose I can post a post-dated reading to the emoncms input I create for this therm conversion factor.
(2) therms to dollars - I have a fixed rate for 12 months, currently $0.061953 per therm, inclusive of taxes. I'm planning to created an input for this value, which will only be updated once a year.
I gather that there are ways to combine inputs to produce a new feed. The calculations I need:
1. CF / 100 * therm factor = therms used. I'd like to log & graph therms used, since it should be a value that is easily comparable over time, regardless of energy content changes (the therm factor) or price changes. (Probably makes sense to simplify the calculation by having the therm factor input be in BTU/CF rather than BTU/CCF.)
2. therms * per therm cost = energy cost
See attached for my current input processing configuration. What I could use is some help in understanding how to add in the calculations described above based on the two new feeds described.
emoncms - calculate & display cost of natural gas
Submitted by ddcarter on Thu, 01/01/2015 - 02:39I've been successful in collecting data from my gas meter via rtlamr & logging to emoncms. The data is in lifetime cubic feet, so I have the processing set up to convert this to a time interval difference, log to a feed, accumulate, and then track daily total.
I'd now like to add in two more components:
(1) cubic feet to therms - on each month's gas bill, my utility company shows the value (currently 1.024 BTU/CCF), which can change from month to month, although usually not by much. I won't know this until after the billing cycle, at which point I suppose I can post a post-dated reading to the emoncms input I create for this therm conversion factor.
(2) therms to dollars - I have a fixed rate for 12 months, currently $0.061953 per therm, inclusive of taxes. I'm planning to created an input for this value, which will only be updated once a year.
I gather that there are ways to combine inputs to produce a new feed. The calculations I need:
1. CF / 100 * therm factor = therms used. I'd like to log & graph therms used, since it should be a value that is easily comparable over time, regardless of energy content changes (the therm factor) or price changes. (Probably makes sense to simplify the calculation by having the therm factor input be in BTU/CF rather than BTU/CCF.)
2. therms * per therm cost = energy cost
See attached for my current input processing configuration. What I could use is some help in understanding how to add in the calculations described above based on the two new feeds described.
Thanks!