How do I analyze and display "delta" consumption data over varying time buckets (windows)?

Configuration
1

My water meter gives me the total consumption to date every 15 minutes.
The ‘Energy’ dashboard allows me to display new consumption in pre-defined, fixed time buckets based on the time range (e.g., hourly, daily, weekly, monthly).

How can I display a bar chart of incremental consumption over an on-the-fly configurable range of time and length of time bucket (window)?

I know I can use a template sensor to calculate and store incremental consumption over an arbitrary time window, but that has 2 disadvantages:

  1. The time window is fixed and must be configured in advance
  2. The data is bucketized and collected going forward – so if I want to look at 30 days, I need to wait 30 days for the data accumulate.

Is there an API I can call to use the data aggregation functionality of the Energy Dashboard to create my own buckets and time ranges for display?

2

I think both MeasureIt (I’m the author) and utility-meter can do this. Have a look at those: MeasureIt and utility_meter.