This automation blueprint sends a notification on high energy price.

Tibber_high_prices.yaml

blueprint:
  name: High electricity price
  description: 'This automation blueprint sends a notification on high energy price.'
  domain: automation
  input:
    energy_sensor:
      name: Tibber price sensor
      selector:
        entity:
          integration: tibber
          domain: sensor
      default: ''
    notify_device:
      name: Device to notify
      description: Device needs to run the official Home Assistant app to receive
        notifications
      selector:
        device:
          integration: mobile_app

mode: single
max_exceeded: silent
variables:
  energy_sensor: !input 'energy_sensor'
  energy_sensor_state: '{{ float(states[energy_sensor].state)}}'
  energy_sensor_max: '{{ float(states[energy_sensor].attributes[''max_price''])}}'
trigger:
  platform: state
  entity_id: !input 'energy_sensor'
condition:
  condition: template
  value_template: '{{energy_sensor_state > 0.9 * energy_sensor_max}}'
action:
  - device_id: !input notify_device
    domain: mobile_app
    type: notify
    title: Electricity price
    message: The electricity price is now {{energy_sensor_state}}