Average hourly value from time series data

Is there any simple way how to create from time series data (electricity consumption) hourly averages over longer period of time (i.e. average consumption in last month for 0-1 am, 1-2 am, 2-3 am, … covering whole day).
Thanks for any hint how to tackle this…

Maybe start here and build your query in InfluxQL or Flux and see what it looks like. Am sure others can help once you post your results (and if you still need help).