@kevin1, this would be really awesome. I commend your interest and dedication for such endeavors.
Are you thinking also of layering on support for the various net metering programs that various utilities provide?..does the OpenEI Utilities Rates Database include these? e.g. for PG&E, are you planning to handle the NEM1* and NEM2* net metering programs?
What about handling the various options/rates that Community Choice Aggregation (CCA) providers for electricity generation? E.g., even though I have the EV-A tariff from PG&E (and NEM2 program too, though I’m ignoring that for this paragraph), my electricity charges is not based on PG&E’s EV-A tariff table, rather it is slight less because the CCA’s (Silicon Valley Clean Electric’s) EV-A GreenStart program’s electricity generation is a bit cheaper that what PG&E’s generation would be.
There is a utility provider in Arizona that has been testing out a residential tariff that includes demand charges. Over the years, I could see demand charges slip more and more into residential rates. Such tariffs could require 15-minute energy usage intervals, rather than just 1-hour intervals.
Anyway, “perfect is the enemy of done”, and any progress towards getting more accurate energy cost info is welcomed. I hope it is a priority for Sense to provide some additional support for more accurate energy cost within the Sense app; I believe it is one of the highest voted “wishlist items” (e.g. TOU pricing). Perhaps your efforts could serve as a catalyst for Sense development of something similar. Good luck.