I have an LP tank that I monitor with the Mopeka integration. I’m sure thera re other similar propane tank monitors. Mine reports in inches, which has to be converted to a more useful measurement. Because of the complex geometry of horizontal tanks, this took some doing. I created an integration that can take any source measurement in distance and convert that into volume presuming your container is a horizontal cylinder with either flat or ellipsoidal endcaps. It exports both a fill level and volume in gallons. For use with liquids that expand, I’ve also included a temperature correction coefficient. By default, this is configured to temperature correct for LP to the standard measuring temperature of 60f. I used this to create a gauge and burn rate to populate my energy dashboard, but you can display this in any way you want.
Just coming across your project on this. I actually just finished up some changes to the native Mopeka integration in HA core to add this functionality for horizontal tanks. I haven’t submitted a PR yet since I’d like to get some feedback and maybe more tank types to test it against.
I’ve added the following enhancements.
- Predefined US propane tank sizes (horizontal and vertical)
- Ability to set a custom tank height for all medium types
- Percentage level sensor that is calculated from the preset ank sizes
- Two diagnostic sensors to show the currently selected medium (fluid) and tank preset.
- Backend calculation to account for horizontal propane tank measurements (due to half sphere end caps).
