How to measure time of energy sensor

[novitibo]

How to write the yaml for template sensor to measure time (like stopwatch) when power of energy sensor is >0kWh?

[revin]

here you have an example:

Time heating on

Hi all I would like to have shown how much time the heater was on on a daily basis, and possibly get also a graph where I can choose to show weekly or monthly. My thermostat is Netatmo Now I have created this sensor - platform: history_stats name: history_stats_caldaia entity_id: climate.termostato state: 'on' type: time end: '{{ now() }}' duration: hours: 24 Is it ok like this? What should I add/modify to get what I want? Thanks