Free Electricity Hours (for next day) Automation

[no1knows]

In case useful for others, this automation runs at 10pm and sets an input_number helper to the number of free hours of electricity the following day (partially courtesy of Gemini):

# Home Assistant automation to calculate the total number of free electricity hours for the next day.
# This automation requires the HomeAssistant-OctopusEnergy integration:
# https://github.com/BottlecapDave/HomeAssistant-OctopusEnergy

id: '1672531200001' # You can replace this with a unique ID
alias: 'Octopus Energy - Calculate Next Day Free Electricity Hours'
description: >-
  Updates an input_number entity with the total hours of free electricity 
  scheduled for the following day from the Octopus Energy integration.

# This automation runs once a day at 10 PM.
# At this time, Octopus has usually published the rates and sessions for the next day.
trigger:
  - platform: time
    at: '22:00:00'

condition: []

action:
  - service: input_number.set_value
    target:
      entity_id: input_number.number_of_free_electricity_hours_coming_up
    data:
      # This template calculates the total duration of all free sessions for the next day.
      value: >-
        {% set tomorrow = (now() + timedelta(days=1)).date() %}

        {# --- IMPORTANT --- #}
        {# Replace the entity_id below with your actual "octoplus_free_electricity_session_events" event entity. #}
        {# You can find this in Developer Tools -> States. It will look like: #}
        {# event.octopus_energy_YOUR_ACCOUNT_ID_octoplus_free_electricity_session_events #}
        {% set sessions = state_attr('event.octopus_energy_electricity_YOUR_ACCOUNT_ID_all_free_electricity_sessions', 'events') %}
        
        {% set total_seconds = namespace(value=0) %}

        {% if sessions is not none %}
          {% for session in sessions %}
            {# Check if the session starts tomorrow #}
            {% if as_datetime(session.start).date() == tomorrow %}
              {% set duration = (as_datetime(session.end) - as_datetime(session.start)).total_seconds() %}
              {% set total_seconds.value = total_seconds.value + duration %}
            {% endif %}
          {% endfor %}
        {% endif %}

        {# Convert total seconds to hours and set the input_number value #}
        {{ total_seconds.value / 3600 }}

You'll need to create an input number helper called "input_number.number_of_free_electricity_hours_coming_up" for this to work.

I use this to leave some un-charged capacity in the batteries, and run a shorter hot water cycle in the morning so there's plenty of headroom to consume lots of electricity when it's free!

[BottlecapDave]

You mind find it easier to use the next_event_duration_in_minutes attribute of the free electricity sensor ;)